2021-01-15 17:33:20

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 00/10] Carry forward IMA measurement log on kexec on ARM64

On kexec file load Integrity Measurement Architecture (IMA) subsystem
may verify the IMA signature of the kernel and initramfs, and measure
it. The command line parameters passed to the kernel in the kexec call
may also be measured by IMA. A remote attestation service can verify
a TPM quote based on the TPM event log, the IMA measurement list, and
the TPM PCR data. This can be achieved only if the IMA measurement log
is carried over from the current kernel to the next kernel across
the kexec call.

powerpc already supports carrying forward the IMA measurement log on
kexec. This patch set adds support for carrying forward the IMA
measurement log on kexec on ARM64.

This patch set moves the platform independent code defined for powerpc
such that it can be reused for other platforms as well. A chosen node
"linux,ima-kexec-buffer" is added to the DTB for ARM64 to hold
the address and the size of the memory reserved to carry
the IMA measurement log.

This patch set has been tested for ARM64 platform using QEMU.
I would like help from the community for testing this change on powerpc.
Thanks.

This patch set is based on
commit 207cdd565dfc ("ima: Don't modify file descriptor mode on the fly")
in https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git
"next-integrity" branch.

Changelog:

v15
- Included Rob's patches in the patch set, and rebased
the changes to "next-integrity" branch.
- Allocate memory for DTB, on arm64, using kmalloc() instead of
vmalloc() to keep it consistent with powerpc implementation.
- Call of_kexec_setup_new_fdt() from setup_new_fdt_ppc64() and
remove setup_new_fdt() in the same patch to keep it bisect safe.

v14
- Select CONFIG_HAVE_IMA_KEXEC for CONFIG_KEXEC_FILE, for powerpc
and arm64, if CONFIG_IMA is enabled.
- Use IS_ENABLED() macro instead of "#ifdef" in remove_ima_buffer(),
ima_get_kexec_buffer(), and ima_free_kexec_buffer().
- Call of_kexec_setup_new_fdt() from setup_new_fdt_ppc64() and
remove setup_new_fdt() in "arch/powerpc/kexec/file_load.c".

v13
- Moved the arch independent functions to drivers/of/kexec.c
and then refactored the code.
- Moved arch_ima_add_kexec_buffer() to
security/integrity/ima/ima_kexec.c

v12
- Use fdt_appendprop_addrrange() in setup_ima_buffer()
to setup the IMA measurement list property in
the device tree.
- Moved architecture independent functions from
"arch/powerpc/kexec/ima.c" to "drivers/of/kexec."
- Deleted "arch/powerpc/kexec/ima.c" and
"arch/powerpc/include/asm/ima.h".

v11
- Rebased the changes on the kexec code refactoring done by
Rob Herring in his "dt/kexec" branch
- Removed "extern" keyword in function declarations
- Removed unnecessary header files included in C files
- Updated patch descriptions per Thiago's comments

v10
- Moved delete_fdt_mem_rsv(), remove_ima_buffer(),
get_ima_kexec_buffer, and get_root_addr_size_cells()
to drivers/of/kexec.c
- Moved arch_ima_add_kexec_buffer() to
security/integrity/ima/ima_kexec.c
- Conditionally define IMA buffer fields in struct kimage_arch

v9
- Moved delete_fdt_mem_rsv() to drivers/of/kexec_fdt.c
- Defined a new function get_ima_kexec_buffer() in
drivers/of/ima_kexec.c to replace do_get_kexec_buffer()
- Changed remove_ima_kexec_buffer() to the original function name
remove_ima_buffer()
- Moved remove_ima_buffer() to drivers/of/ima_kexec.c
- Moved ima_get_kexec_buffer() and ima_free_kexec_buffer()
to security/integrity/ima/ima_kexec.c

v8:
- Moved remove_ima_kexec_buffer(), do_get_kexec_buffer(), and
delete_fdt_mem_rsv() to drivers/of/fdt.c
- Moved ima_dump_measurement_list() and ima_add_kexec_buffer()
back to security/integrity/ima/ima_kexec.c

v7:
- Renamed remove_ima_buffer() to remove_ima_kexec_buffer() and moved
this function definition to kernel.
- Moved delete_fdt_mem_rsv() definition to kernel
- Moved ima_dump_measurement_list() and ima_add_kexec_buffer() to
a new file namely ima_kexec_fdt.c in IMA

v6:
- Remove any existing FDT_PROP_IMA_KEXEC_BUFFER property in the device
tree and also its corresponding memory reservation in the currently
running kernel.
- Moved the function remove_ima_buffer() defined for powerpc to IMA
and renamed the function to ima_remove_kexec_buffer(). Also, moved
delete_fdt_mem_rsv() from powerpc to IMA.

v5:
- Merged get_addr_size_cells() and do_get_kexec_buffer() into a single
function when moving the arch independent code from powerpc to IMA
- Reverted the change to use FDT functions in powerpc code and added
back the original code in get_addr_size_cells() and
do_get_kexec_buffer() for powerpc.
- Added fdt_add_mem_rsv() for ARM64 to reserve the memory for
the IMA log buffer during kexec.
- Fixed the warning reported by kernel test bot for ARM64
arch_ima_add_kexec_buffer() - moved this function to a new file
namely arch/arm64/kernel/ima_kexec.c

v4:
- Submitting the patch series on behalf of the original author
Prakhar Srivastava <[email protected]>
- Moved FDT_PROP_IMA_KEXEC_BUFFER ("linux,ima-kexec-buffer") to
libfdt.h so that it can be shared by multiple platforms.

v3:
Breakup patches further into separate patches.
- Refactoring non architecture specific code out of powerpc
- Update powerpc related code to use fdt functions
- Update IMA buffer read related code to use of functions
- Add support to store the memory information of the IMA
measurement logs to be carried forward.
- Update the property strings to align with documented nodes
https://github.com/devicetree-org/dt-schema/pull/46

v2:
Break patches into separate patches.
- Powerpc related Refactoring
- Updating the docuemntation for chosen node
- Updating arm64 to support IMA buffer pass

v1:
Refactoring carrying over IMA measuremnet logs over Kexec. This patch
moves the non-architecture specific code out of powerpc and adds to
security/ima.(Suggested by Thiago)
Add Documentation regarding the ima-kexec-buffer node in the chosen
node documentation

v0:
Add a layer of abstraction to use the memory reserved by device tree
for ima buffer pass.
Add support for ima buffer pass using reserved memory for arm64 kexec.
Update the arch sepcific code path in kexec file load to store the
ima buffer in the reserved memory. The same reserved memory is read
on kexec or cold boot.

Lakshmi Ramasubramanian (6):
ima: Move arch_ima_add_kexec_buffer() to ima
powerpc: Move arch independent ima kexec functions to
drivers/of/kexec.c
kexec: Use fdt_appendprop_addrrange() to add ima buffer to FDT
powerpc: Delete unused function delete_fdt_mem_rsv()
arm64: Call kmalloc() to allocate DTB buffer
arm64: Add IMA log information in kimage used for kexec

Rob Herring (4):
powerpc: Rename kexec elfcorehdr_addr to elf_headers_mem
of: Add a common kexec FDT setup function
arm64: Use common of_kexec_setup_new_fdt()
powerpc: Use common of_kexec_setup_new_fdt()

arch/arm64/Kconfig | 1 +
arch/arm64/include/asm/kexec.h | 5 +
arch/arm64/kernel/machine_kexec_file.c | 135 +-------
arch/powerpc/Kconfig | 2 +-
arch/powerpc/include/asm/ima.h | 30 --
arch/powerpc/include/asm/kexec.h | 6 +-
arch/powerpc/kexec/Makefile | 7 -
arch/powerpc/kexec/file_load.c | 184 +----------
arch/powerpc/kexec/file_load_64.c | 8 +-
arch/powerpc/kexec/ima.c | 219 -------------
drivers/of/Makefile | 1 +
drivers/of/kexec.c | 429 +++++++++++++++++++++++++
include/linux/of.h | 7 +
security/integrity/ima/ima.h | 4 -
security/integrity/ima/ima_kexec.c | 22 ++
15 files changed, 484 insertions(+), 576 deletions(-)
delete mode 100644 arch/powerpc/include/asm/ima.h
delete mode 100644 arch/powerpc/kexec/ima.c
create mode 100644 drivers/of/kexec.c

--
2.30.0


2021-01-15 17:33:30

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 02/10] of: Add a common kexec FDT setup function

From: Rob Herring <[email protected]>

Both arm64 and powerpc do essentially the same FDT /chosen setup for
kexec. The differences are either omissions that arm64 should have
or additional properties that will be ignored. The setup code can be
combined and shared by both powerpc and arm64.

The differences relative to the arm64 version:
- If /chosen doesn't exist, it will be created (should never happen).
- Any old dtb and initrd reserved memory will be released.
- The new initrd and elfcorehdr are marked reserved.
- "linux,booted-from-kexec" is set.

The differences relative to the powerpc version:
- "kaslr-seed" and "rng-seed" may be set.
- "linux,elfcorehdr" is set.
- Any existing "linux,usable-memory-range" is removed.

Combine the code for setting up the /chosen node in the FDT and updating
the memory reservation for kexec, for powerpc and arm64, in
of_kexec_setup_new_fdt() and move it to "drivers/of/kexec.c".

Signed-off-by: Rob Herring <[email protected]>
Reviewed-by: Thiago Jung Bauermann <[email protected]>
Reviewed-by: Lakshmi Ramasubramanian <[email protected]>
---
drivers/of/Makefile | 1 +
drivers/of/kexec.c | 236 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/of.h | 5 +
3 files changed, 242 insertions(+)
create mode 100644 drivers/of/kexec.c

diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index 6e1e5212f058..8ce11955afde 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -13,5 +13,6 @@ obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o
obj-$(CONFIG_OF_RESOLVE) += resolver.o
obj-$(CONFIG_OF_OVERLAY) += overlay.o
obj-$(CONFIG_OF_NUMA) += of_numa.o
+obj-$(CONFIG_KEXEC_FILE) += kexec.o

obj-$(CONFIG_OF_UNITTEST) += unittest-data/
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
new file mode 100644
index 000000000000..4afd3cc1c04a
--- /dev/null
+++ b/drivers/of/kexec.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 Arm Limited
+ *
+ * Based on arch/arm64/kernel/machine_kexec_file.c:
+ * Copyright (C) 2018 Linaro Limited
+ *
+ * And arch/powerpc/kexec/file_load.c:
+ * Copyright (C) 2016 IBM Corporation
+ */
+
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/libfdt.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/random.h>
+#include <linux/types.h>
+
+/* relevant device tree properties */
+#define FDT_PROP_KEXEC_ELFHDR "linux,elfcorehdr"
+#define FDT_PROP_MEM_RANGE "linux,usable-memory-range"
+#define FDT_PROP_INITRD_START "linux,initrd-start"
+#define FDT_PROP_INITRD_END "linux,initrd-end"
+#define FDT_PROP_BOOTARGS "bootargs"
+#define FDT_PROP_KASLR_SEED "kaslr-seed"
+#define FDT_PROP_RNG_SEED "rng-seed"
+#define RNG_SEED_SIZE 128
+
+/**
+ * fdt_find_and_del_mem_rsv - delete memory reservation with given address and size
+ *
+ * @fdt: Flattened device tree for the current kernel.
+ * @start: Starting address of the reserved memory.
+ * @size: Size of the reserved memory.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned long size)
+{
+ int i, ret, num_rsvs = fdt_num_mem_rsv(fdt);
+
+ for (i = 0; i < num_rsvs; i++) {
+ u64 rsv_start, rsv_size;
+
+ ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
+ if (ret) {
+ pr_err("Malformed device tree.\n");
+ return -EINVAL;
+ }
+
+ if (rsv_start == start && rsv_size == size) {
+ ret = fdt_del_mem_rsv(fdt, i);
+ if (ret) {
+ pr_err("Error deleting device tree reservation.\n");
+ return -EINVAL;
+ }
+
+ return 0;
+ }
+ }
+
+ return -ENOENT;
+}
+
+/*
+ * of_kexec_setup_new_fdt - modify /chosen and memory reservation for the next kernel
+ *
+ * @image: kexec image being loaded.
+ * @fdt: Flattened device tree for the next kernel.
+ * @initrd_load_addr: Address where the next initrd will be loaded.
+ * @initrd_len: Size of the next initrd, or 0 if there will be none.
+ * @cmdline: Command line for the next kernel, or NULL if there will
+ * be none.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
+ unsigned long initrd_load_addr, unsigned long initrd_len,
+ const char *cmdline)
+{
+ int ret, chosen_node;
+ const void *prop;
+
+ /* Remove memory reservation for the current device tree. */
+ ret = fdt_find_and_del_mem_rsv(fdt, __pa(initial_boot_params),
+ fdt_totalsize(initial_boot_params));
+ if (ret == -EINVAL)
+ return ret;
+
+ chosen_node = fdt_path_offset(fdt, "/chosen");
+ if (chosen_node == -FDT_ERR_NOTFOUND)
+ chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
+ "chosen");
+ if (chosen_node < 0) {
+ ret = chosen_node;
+ goto out;
+ }
+
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_KEXEC_ELFHDR);
+ if (ret && ret != -FDT_ERR_NOTFOUND)
+ goto out;
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_MEM_RANGE);
+ if (ret && ret != -FDT_ERR_NOTFOUND)
+ goto out;
+
+ /* Did we boot using an initrd? */
+ prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
+ if (prop) {
+ u64 tmp_start, tmp_end, tmp_size;
+
+ tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
+
+ prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
+ if (!prop)
+ return -EINVAL;
+
+ tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
+
+ /*
+ * kexec reserves exact initrd size, while firmware may
+ * reserve a multiple of PAGE_SIZE, so check for both.
+ */
+ tmp_size = tmp_end - tmp_start;
+ ret = fdt_find_and_del_mem_rsv(fdt, tmp_start, tmp_size);
+ if (ret == -ENOENT)
+ ret = fdt_find_and_del_mem_rsv(fdt, tmp_start,
+ round_up(tmp_size, PAGE_SIZE));
+ if (ret == -EINVAL)
+ return ret;
+ }
+
+ /* add initrd-* */
+ if (initrd_load_addr) {
+ ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_START,
+ initrd_load_addr);
+ if (ret)
+ goto out;
+
+ ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_END,
+ initrd_load_addr + initrd_len);
+ if (ret)
+ goto out;
+
+ ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
+ if (ret)
+ goto out;
+
+ } else {
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_START);
+ if (ret && (ret != -FDT_ERR_NOTFOUND))
+ goto out;
+
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_END);
+ if (ret && (ret != -FDT_ERR_NOTFOUND))
+ goto out;
+ }
+
+ if (image->type == KEXEC_TYPE_CRASH) {
+ /* add linux,elfcorehdr */
+ ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+ FDT_PROP_KEXEC_ELFHDR,
+ image->arch.elf_headers_mem,
+ image->arch.elf_headers_sz);
+ if (ret)
+ goto out;
+
+ /*
+ * Avoid elfcorehdr from being stomped on in kdump kernel by
+ * setting up memory reserve map.
+ */
+ ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
+ image->arch.elf_headers_sz);
+ if (ret)
+ goto out;
+
+ /* add linux,usable-memory-range */
+ ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+ FDT_PROP_MEM_RANGE,
+ crashk_res.start,
+ crashk_res.end - crashk_res.start + 1);
+ if (ret)
+ goto out;
+ }
+
+ /* add bootargs */
+ if (cmdline) {
+ ret = fdt_setprop_string(fdt, chosen_node, FDT_PROP_BOOTARGS, cmdline);
+ if (ret)
+ goto out;
+ } else {
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_BOOTARGS);
+ if (ret && (ret != -FDT_ERR_NOTFOUND))
+ goto out;
+ }
+
+ /* add kaslr-seed */
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_KASLR_SEED);
+ if (ret == -FDT_ERR_NOTFOUND)
+ ret = 0;
+ else if (ret)
+ goto out;
+
+ if (rng_is_initialized()) {
+ u64 seed = get_random_u64();
+
+ ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_KASLR_SEED, seed);
+ if (ret)
+ goto out;
+ } else {
+ pr_notice("RNG is not initialised: omitting \"%s\" property\n",
+ FDT_PROP_KASLR_SEED);
+ }
+
+ /* add rng-seed */
+ if (rng_is_initialized()) {
+ void *rng_seed;
+
+ ret = fdt_setprop_placeholder(fdt, chosen_node, FDT_PROP_RNG_SEED,
+ RNG_SEED_SIZE, &rng_seed);
+ if (ret)
+ goto out;
+ get_random_bytes(rng_seed, RNG_SEED_SIZE);
+ } else {
+ pr_notice("RNG is not initialised: omitting \"%s\" property\n",
+ FDT_PROP_RNG_SEED);
+ }
+
+ ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+
+out:
+ if (ret)
+ return (ret == -FDT_ERR_NOSPACE) ? -ENOMEM : -EINVAL;
+
+ return 0;
+}
diff --git a/include/linux/of.h b/include/linux/of.h
index 5d51891cbf1a..3375f5295875 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -558,6 +558,11 @@ int of_map_id(struct device_node *np, u32 id,
const char *map_name, const char *map_mask_name,
struct device_node **target, u32 *id_out);

+struct kimage;
+int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
+ unsigned long initrd_load_addr, unsigned long initrd_len,
+ const char *cmdline);
+
#else /* CONFIG_OF */

static inline void of_core_init(void)
--
2.30.0

2021-01-15 17:33:32

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 04/10] powerpc: Use common of_kexec_setup_new_fdt()

From: Rob Herring <[email protected]>

The code for setting up the /chosen node in the device tree
and updating the memory reservation for the next kernel has been
moved to of_kexec_setup_new_fdt() defined in "drivers/of/kexec.c".

Use the common of_kexec_setup_new_fdt() to setup the device tree
and update the memory reservation for kexec for powerpc.

Signed-off-by: Rob Herring <[email protected]>
Reviewed-by: Thiago Jung Bauermann <[email protected]>
Reviewed-by: Lakshmi Ramasubramanian <[email protected]>
---
arch/powerpc/kexec/file_load.c | 125 ++-------------------------------
1 file changed, 6 insertions(+), 119 deletions(-)

diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index e452b11df631..956bcb2d1ec2 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -16,6 +16,7 @@

#include <linux/slab.h>
#include <linux/kexec.h>
+#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
#include <asm/setup.h>
@@ -156,132 +157,18 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr, unsigned long initrd_len,
const char *cmdline)
{
- int ret, chosen_node;
- const void *prop;
-
- /* Remove memory reservation for the current device tree. */
- ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
- fdt_totalsize(initial_boot_params));
- if (ret == 0)
- pr_debug("Removed old device tree reservation.\n");
- else if (ret != -ENOENT)
- return ret;
-
- chosen_node = fdt_path_offset(fdt, "/chosen");
- if (chosen_node == -FDT_ERR_NOTFOUND) {
- chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
- "chosen");
- if (chosen_node < 0) {
- pr_err("Error creating /chosen.\n");
- return -EINVAL;
- }
- } else if (chosen_node < 0) {
- pr_err("Malformed device tree: error reading /chosen.\n");
- return -EINVAL;
- }
-
- /* Did we boot using an initrd? */
- prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
- if (prop) {
- uint64_t tmp_start, tmp_end, tmp_size;
-
- tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
-
- prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
- if (!prop) {
- pr_err("Malformed device tree.\n");
- return -EINVAL;
- }
- tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
-
- /*
- * kexec reserves exact initrd size, while firmware may
- * reserve a multiple of PAGE_SIZE, so check for both.
- */
- tmp_size = tmp_end - tmp_start;
- ret = delete_fdt_mem_rsv(fdt, tmp_start, tmp_size);
- if (ret == -ENOENT)
- ret = delete_fdt_mem_rsv(fdt, tmp_start,
- round_up(tmp_size, PAGE_SIZE));
- if (ret == 0)
- pr_debug("Removed old initrd reservation.\n");
- else if (ret != -ENOENT)
- return ret;
-
- /* If there's no new initrd, delete the old initrd's info. */
- if (initrd_len == 0) {
- ret = fdt_delprop(fdt, chosen_node,
- "linux,initrd-start");
- if (ret) {
- pr_err("Error deleting linux,initrd-start.\n");
- return -EINVAL;
- }
-
- ret = fdt_delprop(fdt, chosen_node, "linux,initrd-end");
- if (ret) {
- pr_err("Error deleting linux,initrd-end.\n");
- return -EINVAL;
- }
- }
- }
-
- if (initrd_len) {
- ret = fdt_setprop_u64(fdt, chosen_node,
- "linux,initrd-start",
- initrd_load_addr);
- if (ret < 0)
- goto err;
-
- /* initrd-end is the first address after the initrd image. */
- ret = fdt_setprop_u64(fdt, chosen_node, "linux,initrd-end",
- initrd_load_addr + initrd_len);
- if (ret < 0)
- goto err;
-
- ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
- if (ret) {
- pr_err("Error reserving initrd memory: %s\n",
- fdt_strerror(ret));
- return -EINVAL;
- }
- }
-
- if (cmdline != NULL) {
- ret = fdt_setprop_string(fdt, chosen_node, "bootargs", cmdline);
- if (ret < 0)
- goto err;
- } else {
- ret = fdt_delprop(fdt, chosen_node, "bootargs");
- if (ret && ret != -FDT_ERR_NOTFOUND) {
- pr_err("Error deleting bootargs.\n");
- return -EINVAL;
- }
- }
+ int ret;

- if (image->type == KEXEC_TYPE_CRASH) {
- /*
- * Avoid elfcorehdr from being stomped on in kdump kernel by
- * setting up memory reserve map.
- */
- ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
- image->arch.elf_headers_sz);
- if (ret) {
- pr_err("Error reserving elfcorehdr memory: %s\n",
- fdt_strerror(ret));
- goto err;
- }
- }
+ ret = of_kexec_setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
+ if (ret)
+ goto err;

- ret = setup_ima_buffer(image, fdt, chosen_node);
+ ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
if (ret) {
pr_err("Error setting up the new device tree.\n");
return ret;
}

- ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
- if (ret)
- goto err;
-
return 0;

err:
--
2.30.0

2021-01-15 17:33:50

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 10/10] arm64: Add IMA log information in kimage used for kexec

Address and size of the buffer containing the IMA measurement log need
to be passed from the current kernel to the next kernel on kexec.

Add address and size fields to "struct kimage_arch" for ARM64 platform
to hold the address and size of the IMA measurement log buffer.

Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
is enabled, to indicate that the IMA measurement log information is
present in the device tree for ARM64.

Co-developed-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
Reviewed-by: Thiago Jung Bauermann <[email protected]>
---
arch/arm64/Kconfig | 1 +
arch/arm64/include/asm/kexec.h | 5 +++++
2 files changed, 6 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 1d466addb078..ea7f7fe3dccd 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1094,6 +1094,7 @@ config KEXEC
config KEXEC_FILE
bool "kexec file based system call"
select KEXEC_CORE
+ select HAVE_IMA_KEXEC if IMA
help
This is new version of kexec system call. This system call is
file based and takes file descriptors as system call argument
diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
index d24b527e8c00..2bd19ccb6c43 100644
--- a/arch/arm64/include/asm/kexec.h
+++ b/arch/arm64/include/asm/kexec.h
@@ -100,6 +100,11 @@ struct kimage_arch {
void *elf_headers;
unsigned long elf_headers_mem;
unsigned long elf_headers_sz;
+
+#ifdef CONFIG_IMA_KEXEC
+ phys_addr_t ima_buffer_addr;
+ size_t ima_buffer_size;
+#endif
};

extern const struct kexec_file_ops kexec_image_ops;
--
2.30.0

2021-01-15 17:34:08

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 06/10] powerpc: Move arch independent ima kexec functions to drivers/of/kexec.c

The functions defined in "arch/powerpc/kexec/ima.c" handle setting up
and freeing the resources required to carry over the IMA measurement
list from the current kernel to the next kernel across kexec system call.
These functions do not have architecture specific code, but are
currently limited to powerpc.

Move setup_ima_buffer() call into of_kexec_setup_new_fdt() defined in
"drivers/of/kexec.c". Call of_kexec_setup_new_fdt() from
setup_new_fdt_ppc64() and remove setup_new_fdt() in
"arch/powerpc/kexec/file_load.c".

Move the remaining architecture independent functions from
"arch/powerpc/kexec/ima.c" to "drivers/of/kexec.c".
Delete "arch/powerpc/kexec/ima.c" and "arch/powerpc/include/asm/ima.h".
Remove references to the deleted files in powerpc and in ima.

Co-developed-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
---
arch/powerpc/Kconfig | 2 +-
arch/powerpc/include/asm/ima.h | 27 ----
arch/powerpc/include/asm/kexec.h | 3 -
arch/powerpc/kexec/Makefile | 7 -
arch/powerpc/kexec/file_load.c | 35 -----
arch/powerpc/kexec/file_load_64.c | 4 +-
arch/powerpc/kexec/ima.c | 202 ------------------------
drivers/of/kexec.c | 240 +++++++++++++++++++++++++++++
include/linux/of.h | 2 +
security/integrity/ima/ima.h | 4 -
security/integrity/ima/ima_kexec.c | 1 +
11 files changed, 247 insertions(+), 280 deletions(-)
delete mode 100644 arch/powerpc/include/asm/ima.h
delete mode 100644 arch/powerpc/kexec/ima.c

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index e9f13fe08492..4ddd17215ecf 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -548,7 +548,7 @@ config KEXEC
config KEXEC_FILE
bool "kexec file based system call"
select KEXEC_CORE
- select HAVE_IMA_KEXEC
+ select HAVE_IMA_KEXEC if IMA
select BUILD_BIN2C
select KEXEC_ELF
depends on PPC64
diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h
deleted file mode 100644
index 51f64fd06c19..000000000000
--- a/arch/powerpc/include/asm/ima.h
+++ /dev/null
@@ -1,27 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_POWERPC_IMA_H
-#define _ASM_POWERPC_IMA_H
-
-struct kimage;
-
-int ima_get_kexec_buffer(void **addr, size_t *size);
-int ima_free_kexec_buffer(void);
-
-#ifdef CONFIG_IMA
-void remove_ima_buffer(void *fdt, int chosen_node);
-#else
-static inline void remove_ima_buffer(void *fdt, int chosen_node) {}
-#endif
-
-#ifdef CONFIG_IMA_KEXEC
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);
-#else
-static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
- int chosen_node)
-{
- remove_ima_buffer(fdt, chosen_node);
- return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */
-
-#endif /* _ASM_POWERPC_IMA_H */
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index dbf09d2f36d0..11679fc2cadc 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -123,9 +123,6 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
int setup_purgatory(struct kimage *image, const void *slave_code,
const void *fdt, unsigned long kernel_load_addr,
unsigned long fdt_load_addr);
-int setup_new_fdt(const struct kimage *image, void *fdt,
- unsigned long initrd_load_addr, unsigned long initrd_len,
- const char *cmdline);
int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);

#ifdef CONFIG_PPC64
diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
index 4aff6846c772..b6c52608cb49 100644
--- a/arch/powerpc/kexec/Makefile
+++ b/arch/powerpc/kexec/Makefile
@@ -9,13 +9,6 @@ obj-$(CONFIG_PPC32) += relocate_32.o

obj-$(CONFIG_KEXEC_FILE) += file_load.o ranges.o file_load_$(BITS).o elf_$(BITS).o

-ifdef CONFIG_HAVE_IMA_KEXEC
-ifdef CONFIG_IMA
-obj-y += ima.o
-endif
-endif
-
-
# Disable GCOV, KCOV & sanitizers in odd or sensitive code
GCOV_PROFILE_core_$(BITS).o := n
KCOV_INSTRUMENT_core_$(BITS).o := n
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index 956bcb2d1ec2..5dd3a9c45a2d 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -20,7 +20,6 @@
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
#include <asm/setup.h>
-#include <asm/ima.h>

#define SLAVE_CODE_SIZE 256 /* First 0x100 bytes */

@@ -141,37 +140,3 @@ int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)

return -ENOENT;
}
-
-/*
- * setup_new_fdt - modify /chosen and memory reservation for the next kernel
- * @image: kexec image being loaded.
- * @fdt: Flattened device tree for the next kernel.
- * @initrd_load_addr: Address where the next initrd will be loaded.
- * @initrd_len: Size of the next initrd, or 0 if there will be none.
- * @cmdline: Command line for the next kernel, or NULL if there will
- * be none.
- *
- * Return: 0 on success, or negative errno on error.
- */
-int setup_new_fdt(const struct kimage *image, void *fdt,
- unsigned long initrd_load_addr, unsigned long initrd_len,
- const char *cmdline)
-{
- int ret;
-
- ret = of_kexec_setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
- if (ret)
- goto err;
-
- ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
- if (ret) {
- pr_err("Error setting up the new device tree.\n");
- return ret;
- }
-
- return 0;
-
-err:
- pr_err("Error setting up the new device tree.\n");
- return -EINVAL;
-}
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index a05c19b3cc60..3cab318aa3b9 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -17,6 +17,7 @@
#include <linux/kexec.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
+#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/memblock.h>
#include <linux/slab.h>
@@ -944,7 +945,8 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
struct crash_mem *umem = NULL, *rmem = NULL;
int i, nr_ranges, ret;

- ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
+ ret = of_kexec_setup_new_fdt(image, fdt, initrd_load_addr, initrd_len,
+ cmdline);
if (ret)
goto out;

diff --git a/arch/powerpc/kexec/ima.c b/arch/powerpc/kexec/ima.c
deleted file mode 100644
index 7378d59c0c1e..000000000000
--- a/arch/powerpc/kexec/ima.c
+++ /dev/null
@@ -1,202 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2016 IBM Corporation
- *
- * Authors:
- * Thiago Jung Bauermann <[email protected]>
- */
-
-#include <linux/slab.h>
-#include <linux/kexec.h>
-#include <linux/of.h>
-#include <linux/memblock.h>
-#include <linux/libfdt.h>
-
-static int get_addr_size_cells(int *addr_cells, int *size_cells)
-{
- struct device_node *root;
-
- root = of_find_node_by_path("/");
- if (!root)
- return -EINVAL;
-
- *addr_cells = of_n_addr_cells(root);
- *size_cells = of_n_size_cells(root);
-
- of_node_put(root);
-
- return 0;
-}
-
-static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
- size_t *size)
-{
- int ret, addr_cells, size_cells;
-
- ret = get_addr_size_cells(&addr_cells, &size_cells);
- if (ret)
- return ret;
-
- if (len < 4 * (addr_cells + size_cells))
- return -ENOENT;
-
- *addr = of_read_number(prop, addr_cells);
- *size = of_read_number(prop + 4 * addr_cells, size_cells);
-
- return 0;
-}
-
-/**
- * ima_get_kexec_buffer - get IMA buffer from the previous kernel
- * @addr: On successful return, set to point to the buffer contents.
- * @size: On successful return, set to the buffer size.
- *
- * Return: 0 on success, negative errno on error.
- */
-int ima_get_kexec_buffer(void **addr, size_t *size)
-{
- int ret, len;
- unsigned long tmp_addr;
- size_t tmp_size;
- const void *prop;
-
- prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len);
- if (!prop)
- return -ENOENT;
-
- ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
- if (ret)
- return ret;
-
- *addr = __va(tmp_addr);
- *size = tmp_size;
-
- return 0;
-}
-
-/**
- * ima_free_kexec_buffer - free memory used by the IMA buffer
- */
-int ima_free_kexec_buffer(void)
-{
- int ret;
- unsigned long addr;
- size_t size;
- struct property *prop;
-
- prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL);
- if (!prop)
- return -ENOENT;
-
- ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
- if (ret)
- return ret;
-
- ret = of_remove_property(of_chosen, prop);
- if (ret)
- return ret;
-
- return memblock_free(addr, size);
-
-}
-
-/**
- * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
- *
- * The IMA measurement buffer is of no use to a subsequent kernel, so we always
- * remove it from the device tree.
- */
-void remove_ima_buffer(void *fdt, int chosen_node)
-{
- int ret, len;
- unsigned long addr;
- size_t size;
- const void *prop;
-
- prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
- if (!prop)
- return;
-
- ret = do_get_kexec_buffer(prop, len, &addr, &size);
- fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
- if (ret)
- return;
-
- ret = delete_fdt_mem_rsv(fdt, addr, size);
- if (!ret)
- pr_debug("Removed old IMA buffer reservation.\n");
-}
-
-#ifdef CONFIG_IMA_KEXEC
-static int write_number(void *p, u64 value, int cells)
-{
- if (cells == 1) {
- u32 tmp;
-
- if (value > U32_MAX)
- return -EINVAL;
-
- tmp = cpu_to_be32(value);
- memcpy(p, &tmp, sizeof(tmp));
- } else if (cells == 2) {
- u64 tmp;
-
- tmp = cpu_to_be64(value);
- memcpy(p, &tmp, sizeof(tmp));
- } else
- return -EINVAL;
-
- return 0;
-}
-
-/**
- * setup_ima_buffer - add IMA buffer information to the fdt
- * @image: kexec image being loaded.
- * @fdt: Flattened device tree for the next kernel.
- * @chosen_node: Offset to the chosen node.
- *
- * Return: 0 on success, or negative errno on error.
- */
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
-{
- int ret, addr_cells, size_cells, entry_size;
- u8 value[16];
-
- remove_ima_buffer(fdt, chosen_node);
- if (!image->arch.ima_buffer_size)
- return 0;
-
- ret = get_addr_size_cells(&addr_cells, &size_cells);
- if (ret)
- return ret;
-
- entry_size = 4 * (addr_cells + size_cells);
-
- if (entry_size > sizeof(value))
- return -EINVAL;
-
- ret = write_number(value, image->arch.ima_buffer_addr, addr_cells);
- if (ret)
- return ret;
-
- ret = write_number(value + 4 * addr_cells, image->arch.ima_buffer_size,
- size_cells);
- if (ret)
- return ret;
-
- ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
- entry_size);
- if (ret < 0)
- return -EINVAL;
-
- ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
- image->arch.ima_buffer_size);
- if (ret)
- return -EINVAL;
-
- pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
- image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
-
- return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index 4afd3cc1c04a..450fa6128001 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -11,6 +11,7 @@

#include <linux/kernel.h>
#include <linux/kexec.h>
+#include <linux/memblock.h>
#include <linux/libfdt.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
@@ -63,6 +64,240 @@ static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon
return -ENOENT;
}

+/**
+ * get_addr_size_cells - Get address and size of root node
+ *
+ * @addr_cells: Return address of the root node
+ * @size_cells: Return size of the root node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int get_addr_size_cells(int *addr_cells, int *size_cells)
+{
+ struct device_node *root;
+
+ root = of_find_node_by_path("/");
+ if (!root)
+ return -EINVAL;
+
+ *addr_cells = of_n_addr_cells(root);
+ *size_cells = of_n_size_cells(root);
+
+ of_node_put(root);
+
+ return 0;
+}
+
+/**
+ * do_get_kexec_buffer - Get address and size of device tree property
+ *
+ * @prop: Device tree property
+ * @len: Size of @prop
+ * @addr: Return address of the node
+ * @size: Return size of the node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
+ size_t *size)
+{
+ int ret, addr_cells, size_cells;
+
+ ret = get_addr_size_cells(&addr_cells, &size_cells);
+ if (ret)
+ return ret;
+
+ if (len < 4 * (addr_cells + size_cells))
+ return -ENOENT;
+
+ *addr = of_read_number(prop, addr_cells);
+ *size = of_read_number(prop + 4 * addr_cells, size_cells);
+
+ return 0;
+}
+
+/**
+ * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
+ *
+ * @fdt: Flattened Device Tree to update
+ * @chosen_node: Offset to the chosen node in the device tree
+ *
+ * The IMA measurement buffer is of no use to a subsequent kernel, so we always
+ * remove it from the device tree.
+ */
+static void remove_ima_buffer(void *fdt, int chosen_node)
+{
+ int ret, len;
+ unsigned long addr;
+ size_t size;
+ const void *prop;
+
+ if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
+ return;
+
+ prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
+ if (!prop)
+ return;
+
+ ret = do_get_kexec_buffer(prop, len, &addr, &size);
+ fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
+ if (ret)
+ return;
+
+ ret = fdt_find_and_del_mem_rsv(fdt, addr, size);
+ if (!ret)
+ pr_debug("Removed old IMA buffer reservation.\n");
+}
+
+/**
+ * ima_get_kexec_buffer - get IMA buffer from the previous kernel
+ * @addr: On successful return, set to point to the buffer contents.
+ * @size: On successful return, set to the buffer size.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int ima_get_kexec_buffer(void **addr, size_t *size)
+{
+ int ret, len;
+ unsigned long tmp_addr;
+ size_t tmp_size;
+ const void *prop;
+
+ if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
+ return -ENOTSUPP;
+
+ prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len);
+ if (!prop)
+ return -ENOENT;
+
+ ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
+ if (ret)
+ return ret;
+
+ *addr = __va(tmp_addr);
+ *size = tmp_size;
+
+ return 0;
+}
+
+/**
+ * ima_free_kexec_buffer - free memory used by the IMA buffer
+ */
+int ima_free_kexec_buffer(void)
+{
+ int ret;
+ unsigned long addr;
+ size_t size;
+ struct property *prop;
+
+ if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
+ return -ENOTSUPP;
+
+ prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL);
+ if (!prop)
+ return -ENOENT;
+
+ ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
+ if (ret)
+ return ret;
+
+ ret = of_remove_property(of_chosen, prop);
+ if (ret)
+ return ret;
+
+ return memblock_free(addr, size);
+
+}
+
+#ifdef CONFIG_IMA_KEXEC
+/**
+ * write_number - Convert number to big-endian format
+ *
+ * @p: Buffer to write the number to
+ * @value: Number to convert
+ * @cells: Number of cells
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int write_number(void *p, u64 value, int cells)
+{
+ if (cells == 1) {
+ u32 tmp;
+
+ if (value > U32_MAX)
+ return -EINVAL;
+
+ tmp = cpu_to_be32(value);
+ memcpy(p, &tmp, sizeof(tmp));
+ } else if (cells == 2) {
+ u64 tmp;
+
+ tmp = cpu_to_be64(value);
+ memcpy(p, &tmp, sizeof(tmp));
+ } else
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * setup_ima_buffer - add IMA buffer information to the fdt
+ * @image: kexec image being loaded.
+ * @fdt: Flattened device tree for the next kernel.
+ * @chosen_node: Offset to the chosen node.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int setup_ima_buffer(const struct kimage *image, void *fdt,
+ int chosen_node)
+{
+ int ret, addr_cells, size_cells, entry_size;
+ u8 value[16];
+
+ if (!image->arch.ima_buffer_size)
+ return 0;
+
+ ret = get_addr_size_cells(&addr_cells, &size_cells);
+ if (ret)
+ return ret;
+
+ entry_size = 4 * (addr_cells + size_cells);
+
+ if (entry_size > sizeof(value))
+ return -EINVAL;
+
+ ret = write_number(value, image->arch.ima_buffer_addr, addr_cells);
+ if (ret)
+ return ret;
+
+ ret = write_number(value + 4 * addr_cells, image->arch.ima_buffer_size,
+ size_cells);
+ if (ret)
+ return ret;
+
+ ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
+ entry_size);
+ if (ret < 0)
+ return -EINVAL;
+
+ ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
+ image->arch.ima_buffer_size);
+ if (ret)
+ return -EINVAL;
+
+ pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
+ image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
+
+ return 0;
+}
+#else /* CONFIG_IMA_KEXEC */
+static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
+ int chosen_node)
+{
+ return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */
+
/*
* of_kexec_setup_new_fdt - modify /chosen and memory reservation for the next kernel
*
@@ -227,6 +462,11 @@ int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
}

ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+ if (ret)
+ goto out;
+
+ remove_ima_buffer(fdt, chosen_node);
+ ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));

out:
if (ret)
diff --git a/include/linux/of.h b/include/linux/of.h
index 3375f5295875..48eb2d05c0ec 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -562,6 +562,8 @@ struct kimage;
int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr, unsigned long initrd_len,
const char *cmdline);
+int ima_get_kexec_buffer(void **addr, size_t *size);
+int ima_free_kexec_buffer(void);

#else /* CONFIG_OF */

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 8e8b1e3cb847..cc0906cd3cd6 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -24,10 +24,6 @@

#include "../integrity.h"

-#ifdef CONFIG_HAVE_IMA_KEXEC
-#include <asm/ima.h>
-#endif
-
enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 };
diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c
index 95513c97ce8f..c62bbb586d2e 100644
--- a/security/integrity/ima/ima_kexec.c
+++ b/security/integrity/ima/ima_kexec.c
@@ -10,6 +10,7 @@
#include <linux/seq_file.h>
#include <linux/vmalloc.h>
#include <linux/kexec.h>
+#include <linux/of.h>
#include "ima.h"

#ifdef CONFIG_IMA_KEXEC
--
2.30.0

2021-01-15 17:34:14

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 08/10] powerpc: Delete unused function delete_fdt_mem_rsv()

delete_fdt_mem_rsv() defined in "arch/powerpc/kexec/file_load.c"
has been renamed to fdt_find_and_del_mem_rsv(), and moved to
"drivers/of/kexec.c".

Remove delete_fdt_mem_rsv() in "arch/powerpc/kexec/file_load.c".

Co-developed-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
---
arch/powerpc/include/asm/kexec.h | 1 -
arch/powerpc/kexec/file_load.c | 32 --------------------------------
2 files changed, 33 deletions(-)

diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 11679fc2cadc..b8c270e08481 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -123,7 +123,6 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
int setup_purgatory(struct kimage *image, const void *slave_code,
const void *fdt, unsigned long kernel_load_addr,
unsigned long fdt_load_addr);
-int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);

#ifdef CONFIG_PPC64
struct kexec_buf;
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index 5dd3a9c45a2d..036c8fb48fc3 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -108,35 +108,3 @@ int setup_purgatory(struct kimage *image, const void *slave_code,

return 0;
}
-
-/**
- * delete_fdt_mem_rsv - delete memory reservation with given address and size
- *
- * Return: 0 on success, or negative errno on error.
- */
-int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)
-{
- int i, ret, num_rsvs = fdt_num_mem_rsv(fdt);
-
- for (i = 0; i < num_rsvs; i++) {
- uint64_t rsv_start, rsv_size;
-
- ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
- if (ret) {
- pr_err("Malformed device tree.\n");
- return -EINVAL;
- }
-
- if (rsv_start == start && rsv_size == size) {
- ret = fdt_del_mem_rsv(fdt, i);
- if (ret) {
- pr_err("Error deleting device tree reservation.\n");
- return -EINVAL;
- }
-
- return 0;
- }
- }
-
- return -ENOENT;
-}
--
2.30.0

2021-01-15 17:34:16

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 01/10] powerpc: Rename kexec elfcorehdr_addr to elf_headers_mem

From: Rob Herring <[email protected]>

The architecture specific field, elfcorehdr_addr in struct kimage_arch,
that holds the address of the buffer in memory for ELF core header for
powerpc has a different name than the one used for arm64. This makes
it hard to have a common code for setting up the device tree for
kexec system call.

Rename elfcorehdr_addr to elf_headers_mem to align with arm64 name so
common code can use it.

Signed-off-by: Rob Herring <[email protected]>
Reviewed-by: Thiago Jung Bauermann <[email protected]>
Reviewed-by: Lakshmi Ramasubramanian <[email protected]>
---
arch/powerpc/include/asm/kexec.h | 2 +-
arch/powerpc/kexec/file_load.c | 4 ++--
arch/powerpc/kexec/file_load_64.c | 4 ++--
3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 55d6ede30c19..dbf09d2f36d0 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -108,7 +108,7 @@ struct kimage_arch {
unsigned long backup_start;
void *backup_buf;

- unsigned long elfcorehdr_addr;
+ unsigned long elf_headers_mem;
unsigned long elf_headers_sz;
void *elf_headers;

diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index 9a232bc36c8f..e452b11df631 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -45,7 +45,7 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
return NULL;

elfcorehdr_strlen = sprintf(cmdline_ptr, "elfcorehdr=0x%lx ",
- image->arch.elfcorehdr_addr);
+ image->arch.elf_headers_mem);

if (elfcorehdr_strlen + cmdline_len > COMMAND_LINE_SIZE) {
pr_err("Appending elfcorehdr=<addr> exceeds cmdline size\n");
@@ -263,7 +263,7 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
* Avoid elfcorehdr from being stomped on in kdump kernel by
* setting up memory reserve map.
*/
- ret = fdt_add_mem_rsv(fdt, image->arch.elfcorehdr_addr,
+ ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
image->arch.elf_headers_sz);
if (ret) {
pr_err("Error reserving elfcorehdr memory: %s\n",
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index c69bcf9b547a..a05c19b3cc60 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -815,7 +815,7 @@ static int load_elfcorehdr_segment(struct kimage *image, struct kexec_buf *kbuf)
goto out;
}

- image->arch.elfcorehdr_addr = kbuf->mem;
+ image->arch.elf_headers_mem = kbuf->mem;
image->arch.elf_headers_sz = headers_sz;
image->arch.elf_headers = headers;
out:
@@ -851,7 +851,7 @@ int load_crashdump_segments_ppc64(struct kimage *image,
return ret;
}
pr_debug("Loaded elf core header at 0x%lx, bufsz=0x%lx memsz=0x%lx\n",
- image->arch.elfcorehdr_addr, kbuf->bufsz, kbuf->memsz);
+ image->arch.elf_headers_mem, kbuf->bufsz, kbuf->memsz);

return 0;
}
--
2.30.0

2021-01-15 17:34:30

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer

create_dtb() function allocates kernel virtual memory for
the device tree blob (DTB). This is not consistent with other
architectures, such as powerpc, which calls kmalloc() for allocating
memory for the DTB.

Call kmalloc() to allocate memory for the DTB, and kfree() to free
the allocated memory.

Co-developed-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
---
arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 7de9c47dee7c..51c40143d6fa 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {

int arch_kimage_file_post_load_cleanup(struct kimage *image)
{
- vfree(image->arch.dtb);
+ kfree(image->arch.dtb);
image->arch.dtb = NULL;

vfree(image->arch.elf_headers);
@@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
+ cmdline_len + DTB_EXTRA_SPACE;

for (;;) {
- buf = vmalloc(buf_size);
+ buf = kmalloc(buf_size, GFP_KERNEL);
if (!buf)
return -ENOMEM;

/* duplicate a device tree blob */
ret = fdt_open_into(initial_boot_params, buf, buf_size);
- if (ret)
+ if (ret) {
+ kfree(buf);
return -EINVAL;
+ }

ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
initrd_len, cmdline);
if (ret) {
- vfree(buf);
+ kfree(buf);
if (ret == -ENOMEM) {
/* unlikely, but just in case */
buf_size += DTB_EXTRA_SPACE;
@@ -217,6 +219,6 @@ int load_other_segments(struct kimage *image,
return 0;

out_err:
- vfree(dtb);
+ kfree(dtb);
return ret;
}
--
2.30.0

2021-01-15 17:34:31

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 07/10] kexec: Use fdt_appendprop_addrrange() to add ima buffer to FDT

fdt_appendprop_addrrange() function adds a property, with the given name,
to the device tree at the given node offset, and also sets the address
and size of the property. This function should be used to add
"linux,ima-kexec-buffer" property to the device tree and set the address
and size of the IMA measurement buffer, instead of using custom function.

Use fdt_appendprop_addrrange() to add "linux,ima-kexec-buffer" property
to the device tree. This property holds the address and size of
the IMA measurement buffer that needs to be passed from the current
kernel to the next kernel across kexec system call.

Remove custom code that is used in setup_ima_buffer() to add
"linux,ima-kexec-buffer" property to the device tree.

Co-developed-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
Reviewed-by: Thiago Jung Bauermann <[email protected]>
---
drivers/of/kexec.c | 57 ++++------------------------------------------
1 file changed, 5 insertions(+), 52 deletions(-)

diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index 450fa6128001..49183da2fc34 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -210,36 +210,6 @@ int ima_free_kexec_buffer(void)
}

#ifdef CONFIG_IMA_KEXEC
-/**
- * write_number - Convert number to big-endian format
- *
- * @p: Buffer to write the number to
- * @value: Number to convert
- * @cells: Number of cells
- *
- * Return: 0 on success, or negative errno on error.
- */
-static int write_number(void *p, u64 value, int cells)
-{
- if (cells == 1) {
- u32 tmp;
-
- if (value > U32_MAX)
- return -EINVAL;
-
- tmp = cpu_to_be32(value);
- memcpy(p, &tmp, sizeof(tmp));
- } else if (cells == 2) {
- u64 tmp;
-
- tmp = cpu_to_be64(value);
- memcpy(p, &tmp, sizeof(tmp));
- } else
- return -EINVAL;
-
- return 0;
-}
-
/**
* setup_ima_buffer - add IMA buffer information to the fdt
* @image: kexec image being loaded.
@@ -251,32 +221,15 @@ static int write_number(void *p, u64 value, int cells)
static int setup_ima_buffer(const struct kimage *image, void *fdt,
int chosen_node)
{
- int ret, addr_cells, size_cells, entry_size;
- u8 value[16];
+ int ret;

if (!image->arch.ima_buffer_size)
return 0;

- ret = get_addr_size_cells(&addr_cells, &size_cells);
- if (ret)
- return ret;
-
- entry_size = 4 * (addr_cells + size_cells);
-
- if (entry_size > sizeof(value))
- return -EINVAL;
-
- ret = write_number(value, image->arch.ima_buffer_addr, addr_cells);
- if (ret)
- return ret;
-
- ret = write_number(value + 4 * addr_cells, image->arch.ima_buffer_size,
- size_cells);
- if (ret)
- return ret;
-
- ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
- entry_size);
+ ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+ "linux,ima-kexec-buffer",
+ image->arch.ima_buffer_addr,
+ image->arch.ima_buffer_size);
if (ret < 0)
return -EINVAL;

--
2.30.0

2021-01-15 17:36:23

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: [PATCH v15 05/10] ima: Move arch_ima_add_kexec_buffer() to ima

arch_ima_add_kexec_buffer() defined in "arch/powerpc/kexec/ima.c"
sets up the address and size of the IMA measurement list in
the architecture specific fields in kimage struct. This function does not
have architecture specific code, but is currently limited to powerpc.

Move arch_ima_add_kexec_buffer() to ima.

Co-developed-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Prakhar Srivastava <[email protected]>
Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
Acked-by: Mimi Zohar <[email protected]>
Reviewed-by: Thiago Jung Bauermann <[email protected]>
---
arch/powerpc/include/asm/ima.h | 3 ---
arch/powerpc/kexec/ima.c | 17 -----------------
security/integrity/ima/ima_kexec.c | 21 +++++++++++++++++++++
3 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h
index ead488cf3981..51f64fd06c19 100644
--- a/arch/powerpc/include/asm/ima.h
+++ b/arch/powerpc/include/asm/ima.h
@@ -14,9 +14,6 @@ static inline void remove_ima_buffer(void *fdt, int chosen_node) {}
#endif

#ifdef CONFIG_IMA_KEXEC
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
- size_t size);
-
int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);
#else
static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
diff --git a/arch/powerpc/kexec/ima.c b/arch/powerpc/kexec/ima.c
index 720e50e490b6..7378d59c0c1e 100644
--- a/arch/powerpc/kexec/ima.c
+++ b/arch/powerpc/kexec/ima.c
@@ -128,23 +128,6 @@ void remove_ima_buffer(void *fdt, int chosen_node)
}

#ifdef CONFIG_IMA_KEXEC
-/**
- * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
- *
- * Architectures should use this function to pass on the IMA buffer
- * information to the next kernel.
- *
- * Return: 0 on success, negative errno on error.
- */
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
- size_t size)
-{
- image->arch.ima_buffer_addr = load_addr;
- image->arch.ima_buffer_size = size;
-
- return 0;
-}
-
static int write_number(void *p, u64 value, int cells)
{
if (cells == 1) {
diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c
index 121de3e04af2..95513c97ce8f 100644
--- a/security/integrity/ima/ima_kexec.c
+++ b/security/integrity/ima/ima_kexec.c
@@ -71,6 +71,27 @@ static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer,
return ret;
}

+/**
+ * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
+ *
+ * @image: kimage struct to set IMA buffer data
+ * @load_addr: Starting address where IMA buffer is loaded at
+ * @size: Number of bytes in the IMA buffer
+ *
+ * Architectures should use this function to pass on the IMA buffer
+ * information to the next kernel.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+static int arch_ima_add_kexec_buffer(struct kimage *image,
+ unsigned long load_addr, size_t size)
+{
+ image->arch.ima_buffer_addr = load_addr;
+ image->arch.ima_buffer_size = size;
+
+ return 0;
+}
+
/*
* Called during kexec_file_load so that IMA can add a segment to the kexec
* image for the measurement list for the next kernel.
--
2.30.0

2021-01-17 13:29:58

by Mimi Zohar

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer

Hi Ard,

On Fri, 2021-01-15 at 09:30 -0800, Lakshmi Ramasubramanian wrote:
> create_dtb() function allocates kernel virtual memory for
> the device tree blob (DTB). This is not consistent with other
> architectures, such as powerpc, which calls kmalloc() for allocating
> memory for the DTB.
>
> Call kmalloc() to allocate memory for the DTB, and kfree() to free
> the allocated memory.

The vmalloc() function description says, "vmalloc - allocate virtually
contiguous memory". I'd appreciate your reviewing this patch, in
particular, which replaces vmalloc() with kmalloc().

thanks,

Mimi

>
> Co-developed-by: Prakhar Srivastava <[email protected]>
> Signed-off-by: Prakhar Srivastava <[email protected]>
> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
> ---
> arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
> index 7de9c47dee7c..51c40143d6fa 100644
> --- a/arch/arm64/kernel/machine_kexec_file.c
> +++ b/arch/arm64/kernel/machine_kexec_file.c
> @@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
>
> int arch_kimage_file_post_load_cleanup(struct kimage *image)
> {
> - vfree(image->arch.dtb);
> + kfree(image->arch.dtb);
> image->arch.dtb = NULL;
>
> vfree(image->arch.elf_headers);
> @@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
> + cmdline_len + DTB_EXTRA_SPACE;
>
> for (;;) {
> - buf = vmalloc(buf_size);
> + buf = kmalloc(buf_size, GFP_KERNEL);
> if (!buf)
> return -ENOMEM;
>
> /* duplicate a device tree blob */
> ret = fdt_open_into(initial_boot_params, buf, buf_size);
> - if (ret)
> + if (ret) {
> + kfree(buf);
> return -EINVAL;
> + }
>
> ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
> initrd_len, cmdline);
> if (ret) {
> - vfree(buf);
> + kfree(buf);
> if (ret == -ENOMEM) {
> /* unlikely, but just in case */
> buf_size += DTB_EXTRA_SPACE;
> @@ -217,6 +219,6 @@ int load_other_segments(struct kimage *image,
> return 0;
>
> out_err:
> - vfree(dtb);
> + kfree(dtb);
> return ret;
> }


2021-01-28 00:09:02

by Will Deacon

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer

On Fri, Jan 15, 2021 at 09:30:16AM -0800, Lakshmi Ramasubramanian wrote:
> create_dtb() function allocates kernel virtual memory for
> the device tree blob (DTB). This is not consistent with other
> architectures, such as powerpc, which calls kmalloc() for allocating
> memory for the DTB.
>
> Call kmalloc() to allocate memory for the DTB, and kfree() to free
> the allocated memory.
>
> Co-developed-by: Prakhar Srivastava <[email protected]>
> Signed-off-by: Prakhar Srivastava <[email protected]>
> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
> ---
> arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
> index 7de9c47dee7c..51c40143d6fa 100644
> --- a/arch/arm64/kernel/machine_kexec_file.c
> +++ b/arch/arm64/kernel/machine_kexec_file.c
> @@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
>
> int arch_kimage_file_post_load_cleanup(struct kimage *image)
> {
> - vfree(image->arch.dtb);
> + kfree(image->arch.dtb);
> image->arch.dtb = NULL;
>
> vfree(image->arch.elf_headers);
> @@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
> + cmdline_len + DTB_EXTRA_SPACE;
>
> for (;;) {
> - buf = vmalloc(buf_size);
> + buf = kmalloc(buf_size, GFP_KERNEL);

Is there a functional need for this patch? I build the 'dtbs' target just
now and sdm845-db845c.dtb is approaching 100K, which feels quite large
for kmalloc().

Will

2021-01-28 00:09:02

by Will Deacon

[permalink] [raw]
Subject: Re: [PATCH v15 10/10] arm64: Add IMA log information in kimage used for kexec

On Fri, Jan 15, 2021 at 09:30:17AM -0800, Lakshmi Ramasubramanian wrote:
> Address and size of the buffer containing the IMA measurement log need
> to be passed from the current kernel to the next kernel on kexec.
>
> Add address and size fields to "struct kimage_arch" for ARM64 platform
> to hold the address and size of the IMA measurement log buffer.
>
> Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
> is enabled, to indicate that the IMA measurement log information is
> present in the device tree for ARM64.
>
> Co-developed-by: Prakhar Srivastava <[email protected]>
> Signed-off-by: Prakhar Srivastava <[email protected]>
> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
> Reviewed-by: Thiago Jung Bauermann <[email protected]>
> ---
> arch/arm64/Kconfig | 1 +
> arch/arm64/include/asm/kexec.h | 5 +++++
> 2 files changed, 6 insertions(+)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 1d466addb078..ea7f7fe3dccd 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -1094,6 +1094,7 @@ config KEXEC
> config KEXEC_FILE
> bool "kexec file based system call"
> select KEXEC_CORE
> + select HAVE_IMA_KEXEC if IMA
> help
> This is new version of kexec system call. This system call is
> file based and takes file descriptors as system call argument
> diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
> index d24b527e8c00..2bd19ccb6c43 100644
> --- a/arch/arm64/include/asm/kexec.h
> +++ b/arch/arm64/include/asm/kexec.h
> @@ -100,6 +100,11 @@ struct kimage_arch {
> void *elf_headers;
> unsigned long elf_headers_mem;
> unsigned long elf_headers_sz;
> +
> +#ifdef CONFIG_IMA_KEXEC
> + phys_addr_t ima_buffer_addr;
> + size_t ima_buffer_size;
> +#endif

Why do these need to be in the arch structure instead of 'struct kimage'?

Will

2021-01-28 00:10:04

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: Re: [PATCH v15 10/10] arm64: Add IMA log information in kimage used for kexec

On 1/27/21 8:54 AM, Will Deacon wrote:

Hi Will,

> On Fri, Jan 15, 2021 at 09:30:17AM -0800, Lakshmi Ramasubramanian wrote:
>> Address and size of the buffer containing the IMA measurement log need
>> to be passed from the current kernel to the next kernel on kexec.
>>
>> Add address and size fields to "struct kimage_arch" for ARM64 platform
>> to hold the address and size of the IMA measurement log buffer.
>>
>> Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
>> is enabled, to indicate that the IMA measurement log information is
>> present in the device tree for ARM64.
>>
>> Co-developed-by: Prakhar Srivastava <[email protected]>
>> Signed-off-by: Prakhar Srivastava <[email protected]>
>> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
>> Reviewed-by: Thiago Jung Bauermann <[email protected]>
>> ---
>> arch/arm64/Kconfig | 1 +
>> arch/arm64/include/asm/kexec.h | 5 +++++
>> 2 files changed, 6 insertions(+)
>>
>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>> index 1d466addb078..ea7f7fe3dccd 100644
>> --- a/arch/arm64/Kconfig
>> +++ b/arch/arm64/Kconfig
>> @@ -1094,6 +1094,7 @@ config KEXEC
>> config KEXEC_FILE
>> bool "kexec file based system call"
>> select KEXEC_CORE
>> + select HAVE_IMA_KEXEC if IMA
>> help
>> This is new version of kexec system call. This system call is
>> file based and takes file descriptors as system call argument
>> diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
>> index d24b527e8c00..2bd19ccb6c43 100644
>> --- a/arch/arm64/include/asm/kexec.h
>> +++ b/arch/arm64/include/asm/kexec.h
>> @@ -100,6 +100,11 @@ struct kimage_arch {
>> void *elf_headers;
>> unsigned long elf_headers_mem;
>> unsigned long elf_headers_sz;
>> +
>> +#ifdef CONFIG_IMA_KEXEC
>> + phys_addr_t ima_buffer_addr;
>> + size_t ima_buffer_size;
>> +#endif
>
> Why do these need to be in the arch structure instead of 'struct kimage'?
>

Currently, only powerpc and, with this patch set, arm64 have support for
carrying forward IMA measurement list across kexec system call. The
above fields are used for tracking IMA measurement list.

Do you see a reason to move these fields to "struct kimage"?

thanks,
-lakshmi

2021-01-28 00:10:30

by Will Deacon

[permalink] [raw]
Subject: Re: [PATCH v15 10/10] arm64: Add IMA log information in kimage used for kexec

On Wed, Jan 27, 2021 at 09:56:53AM -0800, Lakshmi Ramasubramanian wrote:
> On 1/27/21 8:54 AM, Will Deacon wrote:
> > On Fri, Jan 15, 2021 at 09:30:17AM -0800, Lakshmi Ramasubramanian wrote:
> > > Address and size of the buffer containing the IMA measurement log need
> > > to be passed from the current kernel to the next kernel on kexec.
> > >
> > > Add address and size fields to "struct kimage_arch" for ARM64 platform
> > > to hold the address and size of the IMA measurement log buffer.
> > >
> > > Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
> > > is enabled, to indicate that the IMA measurement log information is
> > > present in the device tree for ARM64.
> > >
> > > Co-developed-by: Prakhar Srivastava <[email protected]>
> > > Signed-off-by: Prakhar Srivastava <[email protected]>
> > > Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
> > > Reviewed-by: Thiago Jung Bauermann <[email protected]>
> > > ---
> > > arch/arm64/Kconfig | 1 +
> > > arch/arm64/include/asm/kexec.h | 5 +++++
> > > 2 files changed, 6 insertions(+)
> > >
> > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> > > index 1d466addb078..ea7f7fe3dccd 100644
> > > --- a/arch/arm64/Kconfig
> > > +++ b/arch/arm64/Kconfig
> > > @@ -1094,6 +1094,7 @@ config KEXEC
> > > config KEXEC_FILE
> > > bool "kexec file based system call"
> > > select KEXEC_CORE
> > > + select HAVE_IMA_KEXEC if IMA
> > > help
> > > This is new version of kexec system call. This system call is
> > > file based and takes file descriptors as system call argument
> > > diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
> > > index d24b527e8c00..2bd19ccb6c43 100644
> > > --- a/arch/arm64/include/asm/kexec.h
> > > +++ b/arch/arm64/include/asm/kexec.h
> > > @@ -100,6 +100,11 @@ struct kimage_arch {
> > > void *elf_headers;
> > > unsigned long elf_headers_mem;
> > > unsigned long elf_headers_sz;
> > > +
> > > +#ifdef CONFIG_IMA_KEXEC
> > > + phys_addr_t ima_buffer_addr;
> > > + size_t ima_buffer_size;
> > > +#endif
> >
> > Why do these need to be in the arch structure instead of 'struct kimage'?
> >
>
> Currently, only powerpc and, with this patch set, arm64 have support for
> carrying forward IMA measurement list across kexec system call. The above
> fields are used for tracking IMA measurement list.
>
> Do you see a reason to move these fields to "struct kimage"?

If they're gated on CONFIG_IMA_KEXEC, then it seems harmless for them to
be added to the shared structure. Or are you saying that there are
architectures which have CONFIG_IMA_KEXEC but do not want these fields?

Will

2021-01-28 00:11:07

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer

On 1/27/21 8:52 AM, Will Deacon wrote:

Hi Will,

> On Fri, Jan 15, 2021 at 09:30:16AM -0800, Lakshmi Ramasubramanian wrote:
>> create_dtb() function allocates kernel virtual memory for
>> the device tree blob (DTB). This is not consistent with other
>> architectures, such as powerpc, which calls kmalloc() for allocating
>> memory for the DTB.
>>
>> Call kmalloc() to allocate memory for the DTB, and kfree() to free
>> the allocated memory.
>>
>> Co-developed-by: Prakhar Srivastava <[email protected]>
>> Signed-off-by: Prakhar Srivastava <[email protected]>
>> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
>> ---
>> arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
>> 1 file changed, 7 insertions(+), 5 deletions(-)
>>
>> diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
>> index 7de9c47dee7c..51c40143d6fa 100644
>> --- a/arch/arm64/kernel/machine_kexec_file.c
>> +++ b/arch/arm64/kernel/machine_kexec_file.c
>> @@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
>>
>> int arch_kimage_file_post_load_cleanup(struct kimage *image)
>> {
>> - vfree(image->arch.dtb);
>> + kfree(image->arch.dtb);
>> image->arch.dtb = NULL;
>>
>> vfree(image->arch.elf_headers);
>> @@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
>> + cmdline_len + DTB_EXTRA_SPACE;
>>
>> for (;;) {
>> - buf = vmalloc(buf_size);
>> + buf = kmalloc(buf_size, GFP_KERNEL);
>
> Is there a functional need for this patch? I build the 'dtbs' target just
> now and sdm845-db845c.dtb is approaching 100K, which feels quite large
> for kmalloc().

Changing the allocation from vmalloc() to kmalloc() would help us
further consolidate the DTB setup code for powerpc and arm64.

thanks,
-lakshmi


2021-01-28 00:12:04

by Mimi Zohar

[permalink] [raw]
Subject: Re: [PATCH v15 10/10] arm64: Add IMA log information in kimage used for kexec

On Wed, 2021-01-27 at 10:24 -0800, Lakshmi Ramasubramanian wrote:
> On 1/27/21 10:02 AM, Will Deacon wrote:
> > On Wed, Jan 27, 2021 at 09:56:53AM -0800, Lakshmi Ramasubramanian wrote:
> >> On 1/27/21 8:54 AM, Will Deacon wrote:
> >>> On Fri, Jan 15, 2021 at 09:30:17AM -0800, Lakshmi Ramasubramanian wrote:
> >>>> Address and size of the buffer containing the IMA measurement log need
> >>>> to be passed from the current kernel to the next kernel on kexec.
> >>>>
> >>>> Add address and size fields to "struct kimage_arch" for ARM64 platform
> >>>> to hold the address and size of the IMA measurement log buffer.
> >>>>
> >>>> Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
> >>>> is enabled, to indicate that the IMA measurement log information is
> >>>> present in the device tree for ARM64.
> >>>>
> >>>> Co-developed-by: Prakhar Srivastava <[email protected]>
> >>>> Signed-off-by: Prakhar Srivastava <[email protected]>
> >>>> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
> >>>> Reviewed-by: Thiago Jung Bauermann <[email protected]>
> >>>> ---
> >>>> arch/arm64/Kconfig | 1 +
> >>>> arch/arm64/include/asm/kexec.h | 5 +++++
> >>>> 2 files changed, 6 insertions(+)
> >>>>
> >>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> >>>> index 1d466addb078..ea7f7fe3dccd 100644
> >>>> --- a/arch/arm64/Kconfig
> >>>> +++ b/arch/arm64/Kconfig
> >>>> @@ -1094,6 +1094,7 @@ config KEXEC
> >>>> config KEXEC_FILE
> >>>> bool "kexec file based system call"
> >>>> select KEXEC_CORE
> >>>> + select HAVE_IMA_KEXEC if IMA
> >>>> help
> >>>> This is new version of kexec system call. This system call is
> >>>> file based and takes file descriptors as system call argument
> >>>> diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
> >>>> index d24b527e8c00..2bd19ccb6c43 100644
> >>>> --- a/arch/arm64/include/asm/kexec.h
> >>>> +++ b/arch/arm64/include/asm/kexec.h
> >>>> @@ -100,6 +100,11 @@ struct kimage_arch {
> >>>> void *elf_headers;
> >>>> unsigned long elf_headers_mem;
> >>>> unsigned long elf_headers_sz;
> >>>> +
> >>>> +#ifdef CONFIG_IMA_KEXEC
> >>>> + phys_addr_t ima_buffer_addr;
> >>>> + size_t ima_buffer_size;
> >>>> +#endif
> >>>
> >>> Why do these need to be in the arch structure instead of 'struct kimage'?
> >>>
> >>
> >> Currently, only powerpc and, with this patch set, arm64 have support for
> >> carrying forward IMA measurement list across kexec system call. The above
> >> fields are used for tracking IMA measurement list.
> >>
> >> Do you see a reason to move these fields to "struct kimage"?
> >
> > If they're gated on CONFIG_IMA_KEXEC, then it seems harmless for them to
> > be added to the shared structure. Or are you saying that there are
> > architectures which have CONFIG_IMA_KEXEC but do not want these fields?
> >
>
> As far as I know, there are no other architectures that define
> CONFIG_IMA_KEXEC, but do not use these fields.

Yes, CONFIG_IMA_KEXEC enables "carrying the IMA measurement list across
a soft boot". The only arch that currently carries the IMA
measurement across kexec is powerpc.

Mimi

2021-01-28 00:13:04

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: Re: [PATCH v15 10/10] arm64: Add IMA log information in kimage used for kexec

On 1/27/21 10:02 AM, Will Deacon wrote:
> On Wed, Jan 27, 2021 at 09:56:53AM -0800, Lakshmi Ramasubramanian wrote:
>> On 1/27/21 8:54 AM, Will Deacon wrote:
>>> On Fri, Jan 15, 2021 at 09:30:17AM -0800, Lakshmi Ramasubramanian wrote:
>>>> Address and size of the buffer containing the IMA measurement log need
>>>> to be passed from the current kernel to the next kernel on kexec.
>>>>
>>>> Add address and size fields to "struct kimage_arch" for ARM64 platform
>>>> to hold the address and size of the IMA measurement log buffer.
>>>>
>>>> Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
>>>> is enabled, to indicate that the IMA measurement log information is
>>>> present in the device tree for ARM64.
>>>>
>>>> Co-developed-by: Prakhar Srivastava <[email protected]>
>>>> Signed-off-by: Prakhar Srivastava <[email protected]>
>>>> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
>>>> Reviewed-by: Thiago Jung Bauermann <[email protected]>
>>>> ---
>>>> arch/arm64/Kconfig | 1 +
>>>> arch/arm64/include/asm/kexec.h | 5 +++++
>>>> 2 files changed, 6 insertions(+)
>>>>
>>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>>>> index 1d466addb078..ea7f7fe3dccd 100644
>>>> --- a/arch/arm64/Kconfig
>>>> +++ b/arch/arm64/Kconfig
>>>> @@ -1094,6 +1094,7 @@ config KEXEC
>>>> config KEXEC_FILE
>>>> bool "kexec file based system call"
>>>> select KEXEC_CORE
>>>> + select HAVE_IMA_KEXEC if IMA
>>>> help
>>>> This is new version of kexec system call. This system call is
>>>> file based and takes file descriptors as system call argument
>>>> diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
>>>> index d24b527e8c00..2bd19ccb6c43 100644
>>>> --- a/arch/arm64/include/asm/kexec.h
>>>> +++ b/arch/arm64/include/asm/kexec.h
>>>> @@ -100,6 +100,11 @@ struct kimage_arch {
>>>> void *elf_headers;
>>>> unsigned long elf_headers_mem;
>>>> unsigned long elf_headers_sz;
>>>> +
>>>> +#ifdef CONFIG_IMA_KEXEC
>>>> + phys_addr_t ima_buffer_addr;
>>>> + size_t ima_buffer_size;
>>>> +#endif
>>>
>>> Why do these need to be in the arch structure instead of 'struct kimage'?
>>>
>>
>> Currently, only powerpc and, with this patch set, arm64 have support for
>> carrying forward IMA measurement list across kexec system call. The above
>> fields are used for tracking IMA measurement list.
>>
>> Do you see a reason to move these fields to "struct kimage"?
>
> If they're gated on CONFIG_IMA_KEXEC, then it seems harmless for them to
> be added to the shared structure. Or are you saying that there are
> architectures which have CONFIG_IMA_KEXEC but do not want these fields?
>

As far as I know, there are no other architectures that define
CONFIG_IMA_KEXEC, but do not use these fields.

Mimi - please correct me if I am wrong.

thanks,
-lakshmi




2021-01-28 00:13:12

by Will Deacon

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer

On Wed, Jan 27, 2021 at 09:59:38AM -0800, Lakshmi Ramasubramanian wrote:
> On 1/27/21 8:52 AM, Will Deacon wrote:
>
> Hi Will,
>
> > On Fri, Jan 15, 2021 at 09:30:16AM -0800, Lakshmi Ramasubramanian wrote:
> > > create_dtb() function allocates kernel virtual memory for
> > > the device tree blob (DTB). This is not consistent with other
> > > architectures, such as powerpc, which calls kmalloc() for allocating
> > > memory for the DTB.
> > >
> > > Call kmalloc() to allocate memory for the DTB, and kfree() to free
> > > the allocated memory.
> > >
> > > Co-developed-by: Prakhar Srivastava <[email protected]>
> > > Signed-off-by: Prakhar Srivastava <[email protected]>
> > > Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
> > > ---
> > > arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
> > > 1 file changed, 7 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
> > > index 7de9c47dee7c..51c40143d6fa 100644
> > > --- a/arch/arm64/kernel/machine_kexec_file.c
> > > +++ b/arch/arm64/kernel/machine_kexec_file.c
> > > @@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
> > > int arch_kimage_file_post_load_cleanup(struct kimage *image)
> > > {
> > > - vfree(image->arch.dtb);
> > > + kfree(image->arch.dtb);
> > > image->arch.dtb = NULL;
> > > vfree(image->arch.elf_headers);
> > > @@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
> > > + cmdline_len + DTB_EXTRA_SPACE;
> > > for (;;) {
> > > - buf = vmalloc(buf_size);
> > > + buf = kmalloc(buf_size, GFP_KERNEL);
> >
> > Is there a functional need for this patch? I build the 'dtbs' target just
> > now and sdm845-db845c.dtb is approaching 100K, which feels quite large
> > for kmalloc().
>
> Changing the allocation from vmalloc() to kmalloc() would help us further
> consolidate the DTB setup code for powerpc and arm64.

Ok, but at the risk of allocation failure. Can powerpc use vmalloc()
instead?

Will

2021-01-28 00:47:39

by Will Deacon

[permalink] [raw]
Subject: Re: [PATCH v15 10/10] arm64: Add IMA log information in kimage used for kexec

On Wed, Jan 27, 2021 at 01:31:02PM -0500, Mimi Zohar wrote:
> On Wed, 2021-01-27 at 10:24 -0800, Lakshmi Ramasubramanian wrote:
> > On 1/27/21 10:02 AM, Will Deacon wrote:
> > > On Wed, Jan 27, 2021 at 09:56:53AM -0800, Lakshmi Ramasubramanian wrote:
> > >> On 1/27/21 8:54 AM, Will Deacon wrote:
> > >>> On Fri, Jan 15, 2021 at 09:30:17AM -0800, Lakshmi Ramasubramanian wrote:
> > >>>> Address and size of the buffer containing the IMA measurement log need
> > >>>> to be passed from the current kernel to the next kernel on kexec.
> > >>>>
> > >>>> Add address and size fields to "struct kimage_arch" for ARM64 platform
> > >>>> to hold the address and size of the IMA measurement log buffer.
> > >>>>
> > >>>> Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
> > >>>> is enabled, to indicate that the IMA measurement log information is
> > >>>> present in the device tree for ARM64.
> > >>>>
> > >>>> Co-developed-by: Prakhar Srivastava <[email protected]>
> > >>>> Signed-off-by: Prakhar Srivastava <[email protected]>
> > >>>> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
> > >>>> Reviewed-by: Thiago Jung Bauermann <[email protected]>
> > >>>> ---
> > >>>> arch/arm64/Kconfig | 1 +
> > >>>> arch/arm64/include/asm/kexec.h | 5 +++++
> > >>>> 2 files changed, 6 insertions(+)
> > >>>>
> > >>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> > >>>> index 1d466addb078..ea7f7fe3dccd 100644
> > >>>> --- a/arch/arm64/Kconfig
> > >>>> +++ b/arch/arm64/Kconfig
> > >>>> @@ -1094,6 +1094,7 @@ config KEXEC
> > >>>> config KEXEC_FILE
> > >>>> bool "kexec file based system call"
> > >>>> select KEXEC_CORE
> > >>>> + select HAVE_IMA_KEXEC if IMA
> > >>>> help
> > >>>> This is new version of kexec system call. This system call is
> > >>>> file based and takes file descriptors as system call argument
> > >>>> diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
> > >>>> index d24b527e8c00..2bd19ccb6c43 100644
> > >>>> --- a/arch/arm64/include/asm/kexec.h
> > >>>> +++ b/arch/arm64/include/asm/kexec.h
> > >>>> @@ -100,6 +100,11 @@ struct kimage_arch {
> > >>>> void *elf_headers;
> > >>>> unsigned long elf_headers_mem;
> > >>>> unsigned long elf_headers_sz;
> > >>>> +
> > >>>> +#ifdef CONFIG_IMA_KEXEC
> > >>>> + phys_addr_t ima_buffer_addr;
> > >>>> + size_t ima_buffer_size;
> > >>>> +#endif
> > >>>
> > >>> Why do these need to be in the arch structure instead of 'struct kimage'?
> > >>>
> > >>
> > >> Currently, only powerpc and, with this patch set, arm64 have support for
> > >> carrying forward IMA measurement list across kexec system call. The above
> > >> fields are used for tracking IMA measurement list.
> > >>
> > >> Do you see a reason to move these fields to "struct kimage"?
> > >
> > > If they're gated on CONFIG_IMA_KEXEC, then it seems harmless for them to
> > > be added to the shared structure. Or are you saying that there are
> > > architectures which have CONFIG_IMA_KEXEC but do not want these fields?
> > >
> >
> > As far as I know, there are no other architectures that define
> > CONFIG_IMA_KEXEC, but do not use these fields.
>
> Yes, CONFIG_IMA_KEXEC enables "carrying the IMA measurement list across
> a soft boot". The only arch that currently carries the IMA
> measurement across kexec is powerpc.

Ok, in which case this sounds like it should be in the shared structure, no?

Will

2021-01-28 04:06:58

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer

On 1/27/21 7:52 PM, Thiago Jung Bauermann wrote:
>
> Will Deacon <[email protected]> writes:
>
>> On Wed, Jan 27, 2021 at 09:59:38AM -0800, Lakshmi Ramasubramanian wrote:
>>> On 1/27/21 8:52 AM, Will Deacon wrote:
>>>
>>> Hi Will,
>>>
>>>> On Fri, Jan 15, 2021 at 09:30:16AM -0800, Lakshmi Ramasubramanian wrote:
>>>>> create_dtb() function allocates kernel virtual memory for
>>>>> the device tree blob (DTB). This is not consistent with other
>>>>> architectures, such as powerpc, which calls kmalloc() for allocating
>>>>> memory for the DTB.
>>>>>
>>>>> Call kmalloc() to allocate memory for the DTB, and kfree() to free
>>>>> the allocated memory.
>>>>>
>>>>> Co-developed-by: Prakhar Srivastava <[email protected]>
>>>>> Signed-off-by: Prakhar Srivastava <[email protected]>
>>>>> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
>>>>> ---
>>>>> arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
>>>>> 1 file changed, 7 insertions(+), 5 deletions(-)
>>>>>
>>>>> diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
>>>>> index 7de9c47dee7c..51c40143d6fa 100644
>>>>> --- a/arch/arm64/kernel/machine_kexec_file.c
>>>>> +++ b/arch/arm64/kernel/machine_kexec_file.c
>>>>> @@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
>>>>> int arch_kimage_file_post_load_cleanup(struct kimage *image)
>>>>> {
>>>>> - vfree(image->arch.dtb);
>>>>> + kfree(image->arch.dtb);
>>>>> image->arch.dtb = NULL;
>>>>> vfree(image->arch.elf_headers);
>>>>> @@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
>>>>> + cmdline_len + DTB_EXTRA_SPACE;
>>>>> for (;;) {
>>>>> - buf = vmalloc(buf_size);
>>>>> + buf = kmalloc(buf_size, GFP_KERNEL);
>>>>
>>>> Is there a functional need for this patch? I build the 'dtbs' target just
>>>> now and sdm845-db845c.dtb is approaching 100K, which feels quite large
>>>> for kmalloc().
>>>
>>> Changing the allocation from vmalloc() to kmalloc() would help us further
>>> consolidate the DTB setup code for powerpc and arm64.
>>
>> Ok, but at the risk of allocation failure. Can powerpc use vmalloc()
>> instead?
>
> I believe this patch stems from this suggestion by Rob Herring:
>
>> This could be taken a step further and do the allocation of the new
>> FDT. The difference is arm64 uses vmalloc and powerpc uses kmalloc. The
>> arm64 version also retries with a bigger allocation. That seems
>> unnecessary.
>
> in https://lore.kernel.org/linux-integrity/[email protected]/
>
> The problem is that this patch implements only part of the suggestion,
> which isn't useful in itself. So the patch series should either drop
> this patch or consolidate the FDT allocation between the arches.
>
> I just tested on powernv and pseries platforms and powerpc can use
> vmalloc for the FDT buffer.
>

Thanks for verifying on powerpc platform Thiago.

I'll update the patch to do the following:

=> Use vmalloc for FDT buffer allocation on powerpc
=> Keep vmalloc for arm64, but remove the retry on allocation.
=> Also, there was a memory leak of FDT buffer in the error code path on
arm64, which I'll fix as well.

Did I miss anything?

thanks,
-lakshmi

2021-01-28 04:09:11

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: Re: [PATCH v15 10/10] arm64: Add IMA log information in kimage used for kexec

On 1/27/21 3:13 PM, Will Deacon wrote:
> On Wed, Jan 27, 2021 at 01:31:02PM -0500, Mimi Zohar wrote:
>> On Wed, 2021-01-27 at 10:24 -0800, Lakshmi Ramasubramanian wrote:
>>> On 1/27/21 10:02 AM, Will Deacon wrote:
>>>> On Wed, Jan 27, 2021 at 09:56:53AM -0800, Lakshmi Ramasubramanian wrote:
>>>>> On 1/27/21 8:54 AM, Will Deacon wrote:
>>>>>> On Fri, Jan 15, 2021 at 09:30:17AM -0800, Lakshmi Ramasubramanian wrote:
>>>>>>> Address and size of the buffer containing the IMA measurement log need
>>>>>>> to be passed from the current kernel to the next kernel on kexec.
>>>>>>>
>>>>>>> Add address and size fields to "struct kimage_arch" for ARM64 platform
>>>>>>> to hold the address and size of the IMA measurement log buffer.
>>>>>>>
>>>>>>> Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
>>>>>>> is enabled, to indicate that the IMA measurement log information is
>>>>>>> present in the device tree for ARM64.
>>>>>>>
>>>>>>> Co-developed-by: Prakhar Srivastava <[email protected]>
>>>>>>> Signed-off-by: Prakhar Srivastava <[email protected]>
>>>>>>> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
>>>>>>> Reviewed-by: Thiago Jung Bauermann <[email protected]>
>>>>>>> ---
>>>>>>> arch/arm64/Kconfig | 1 +
>>>>>>> arch/arm64/include/asm/kexec.h | 5 +++++
>>>>>>> 2 files changed, 6 insertions(+)
>>>>>>>
>>>>>>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>>>>>>> index 1d466addb078..ea7f7fe3dccd 100644
>>>>>>> --- a/arch/arm64/Kconfig
>>>>>>> +++ b/arch/arm64/Kconfig
>>>>>>> @@ -1094,6 +1094,7 @@ config KEXEC
>>>>>>> config KEXEC_FILE
>>>>>>> bool "kexec file based system call"
>>>>>>> select KEXEC_CORE
>>>>>>> + select HAVE_IMA_KEXEC if IMA
>>>>>>> help
>>>>>>> This is new version of kexec system call. This system call is
>>>>>>> file based and takes file descriptors as system call argument
>>>>>>> diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
>>>>>>> index d24b527e8c00..2bd19ccb6c43 100644
>>>>>>> --- a/arch/arm64/include/asm/kexec.h
>>>>>>> +++ b/arch/arm64/include/asm/kexec.h
>>>>>>> @@ -100,6 +100,11 @@ struct kimage_arch {
>>>>>>> void *elf_headers;
>>>>>>> unsigned long elf_headers_mem;
>>>>>>> unsigned long elf_headers_sz;
>>>>>>> +
>>>>>>> +#ifdef CONFIG_IMA_KEXEC
>>>>>>> + phys_addr_t ima_buffer_addr;
>>>>>>> + size_t ima_buffer_size;
>>>>>>> +#endif
>>>>>>
>>>>>> Why do these need to be in the arch structure instead of 'struct kimage'?
>>>>>>
>>>>>
>>>>> Currently, only powerpc and, with this patch set, arm64 have support for
>>>>> carrying forward IMA measurement list across kexec system call. The above
>>>>> fields are used for tracking IMA measurement list.
>>>>>
>>>>> Do you see a reason to move these fields to "struct kimage"?
>>>>
>>>> If they're gated on CONFIG_IMA_KEXEC, then it seems harmless for them to
>>>> be added to the shared structure. Or are you saying that there are
>>>> architectures which have CONFIG_IMA_KEXEC but do not want these fields?
>>>>
>>>
>>> As far as I know, there are no other architectures that define
>>> CONFIG_IMA_KEXEC, but do not use these fields.
>>
>> Yes, CONFIG_IMA_KEXEC enables "carrying the IMA measurement list across
>> a soft boot". The only arch that currently carries the IMA
>> measurement across kexec is powerpc.
>
> Ok, in which case this sounds like it should be in the shared structure, no?
>

Ok - I'll move the IMA kexec buffer fields from "struct kimage_arch" to
"struct kimage" for both powerpc and arm64.

thanks,
-lakshmi


2021-01-28 04:18:25

by Thiago Jung Bauermann

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer


Lakshmi Ramasubramanian <[email protected]> writes:

> On 1/27/21 7:52 PM, Thiago Jung Bauermann wrote:
>> Will Deacon <[email protected]> writes:
>>
>>> On Wed, Jan 27, 2021 at 09:59:38AM -0800, Lakshmi Ramasubramanian wrote:
>>>> On 1/27/21 8:52 AM, Will Deacon wrote:
>>>>
>>>> Hi Will,
>>>>
>>>>> On Fri, Jan 15, 2021 at 09:30:16AM -0800, Lakshmi Ramasubramanian wrote:
>>>>>> create_dtb() function allocates kernel virtual memory for
>>>>>> the device tree blob (DTB). This is not consistent with other
>>>>>> architectures, such as powerpc, which calls kmalloc() for allocating
>>>>>> memory for the DTB.
>>>>>>
>>>>>> Call kmalloc() to allocate memory for the DTB, and kfree() to free
>>>>>> the allocated memory.
>>>>>>
>>>>>> Co-developed-by: Prakhar Srivastava <[email protected]>
>>>>>> Signed-off-by: Prakhar Srivastava <[email protected]>
>>>>>> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
>>>>>> ---
>>>>>> arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
>>>>>> 1 file changed, 7 insertions(+), 5 deletions(-)
>>>>>>
>>>>>> diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
>>>>>> index 7de9c47dee7c..51c40143d6fa 100644
>>>>>> --- a/arch/arm64/kernel/machine_kexec_file.c
>>>>>> +++ b/arch/arm64/kernel/machine_kexec_file.c
>>>>>> @@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
>>>>>> int arch_kimage_file_post_load_cleanup(struct kimage *image)
>>>>>> {
>>>>>> - vfree(image->arch.dtb);
>>>>>> + kfree(image->arch.dtb);
>>>>>> image->arch.dtb = NULL;
>>>>>> vfree(image->arch.elf_headers);
>>>>>> @@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
>>>>>> + cmdline_len + DTB_EXTRA_SPACE;
>>>>>> for (;;) {
>>>>>> - buf = vmalloc(buf_size);
>>>>>> + buf = kmalloc(buf_size, GFP_KERNEL);
>>>>>
>>>>> Is there a functional need for this patch? I build the 'dtbs' target just
>>>>> now and sdm845-db845c.dtb is approaching 100K, which feels quite large
>>>>> for kmalloc().
>>>>
>>>> Changing the allocation from vmalloc() to kmalloc() would help us further
>>>> consolidate the DTB setup code for powerpc and arm64.
>>>
>>> Ok, but at the risk of allocation failure. Can powerpc use vmalloc()
>>> instead?
>> I believe this patch stems from this suggestion by Rob Herring:
>>
>>> This could be taken a step further and do the allocation of the new
>>> FDT. The difference is arm64 uses vmalloc and powerpc uses kmalloc. The
>>> arm64 version also retries with a bigger allocation. That seems
>>> unnecessary.
>> in
>> https://lore.kernel.org/linux-integrity/[email protected]/
>> The problem is that this patch implements only part of the suggestion,
>> which isn't useful in itself. So the patch series should either drop
>> this patch or consolidate the FDT allocation between the arches.
>> I just tested on powernv and pseries platforms and powerpc can use
>> vmalloc for the FDT buffer.
>>
>
> Thanks for verifying on powerpc platform Thiago.
>
> I'll update the patch to do the following:
>
> => Use vmalloc for FDT buffer allocation on powerpc
> => Keep vmalloc for arm64, but remove the retry on allocation.
> => Also, there was a memory leak of FDT buffer in the error code path on arm64,
> which I'll fix as well.
>
> Did I miss anything?

Yes, you missed the second part of Rob's suggestion I was mentioning,
which is factoring out the code which allocates the new FDT from both
arm64 and powerpc.

--
Thiago Jung Bauermann
IBM Linux Technology Center

2021-01-28 04:33:32

by Thiago Jung Bauermann

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer


Will Deacon <[email protected]> writes:

> On Wed, Jan 27, 2021 at 09:59:38AM -0800, Lakshmi Ramasubramanian wrote:
>> On 1/27/21 8:52 AM, Will Deacon wrote:
>>
>> Hi Will,
>>
>> > On Fri, Jan 15, 2021 at 09:30:16AM -0800, Lakshmi Ramasubramanian wrote:
>> > > create_dtb() function allocates kernel virtual memory for
>> > > the device tree blob (DTB). This is not consistent with other
>> > > architectures, such as powerpc, which calls kmalloc() for allocating
>> > > memory for the DTB.
>> > >
>> > > Call kmalloc() to allocate memory for the DTB, and kfree() to free
>> > > the allocated memory.
>> > >
>> > > Co-developed-by: Prakhar Srivastava <[email protected]>
>> > > Signed-off-by: Prakhar Srivastava <[email protected]>
>> > > Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
>> > > ---
>> > > arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
>> > > 1 file changed, 7 insertions(+), 5 deletions(-)
>> > >
>> > > diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
>> > > index 7de9c47dee7c..51c40143d6fa 100644
>> > > --- a/arch/arm64/kernel/machine_kexec_file.c
>> > > +++ b/arch/arm64/kernel/machine_kexec_file.c
>> > > @@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
>> > > int arch_kimage_file_post_load_cleanup(struct kimage *image)
>> > > {
>> > > - vfree(image->arch.dtb);
>> > > + kfree(image->arch.dtb);
>> > > image->arch.dtb = NULL;
>> > > vfree(image->arch.elf_headers);
>> > > @@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
>> > > + cmdline_len + DTB_EXTRA_SPACE;
>> > > for (;;) {
>> > > - buf = vmalloc(buf_size);
>> > > + buf = kmalloc(buf_size, GFP_KERNEL);
>> >
>> > Is there a functional need for this patch? I build the 'dtbs' target just
>> > now and sdm845-db845c.dtb is approaching 100K, which feels quite large
>> > for kmalloc().
>>
>> Changing the allocation from vmalloc() to kmalloc() would help us further
>> consolidate the DTB setup code for powerpc and arm64.
>
> Ok, but at the risk of allocation failure. Can powerpc use vmalloc()
> instead?

I believe this patch stems from this suggestion by Rob Herring:

> This could be taken a step further and do the allocation of the new
> FDT. The difference is arm64 uses vmalloc and powerpc uses kmalloc. The
> arm64 version also retries with a bigger allocation. That seems
> unnecessary.

in https://lore.kernel.org/linux-integrity/[email protected]/

The problem is that this patch implements only part of the suggestion,
which isn't useful in itself. So the patch series should either drop
this patch or consolidate the FDT allocation between the arches.

I just tested on powernv and pseries platforms and powerpc can use
vmalloc for the FDT buffer.

--
Thiago Jung Bauermann
IBM Linux Technology Center

2021-01-28 04:35:25

by Lakshmi Ramasubramanian

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer

On 1/27/21 8:14 PM, Thiago Jung Bauermann wrote:
>
> Lakshmi Ramasubramanian <[email protected]> writes:
>
>> On 1/27/21 7:52 PM, Thiago Jung Bauermann wrote:
>>> Will Deacon <[email protected]> writes:
>>>
>>>> On Wed, Jan 27, 2021 at 09:59:38AM -0800, Lakshmi Ramasubramanian wrote:
>>>>> On 1/27/21 8:52 AM, Will Deacon wrote:
>>>>>
>>>>> Hi Will,
>>>>>
>>>>>> On Fri, Jan 15, 2021 at 09:30:16AM -0800, Lakshmi Ramasubramanian wrote:
>>>>>>> create_dtb() function allocates kernel virtual memory for
>>>>>>> the device tree blob (DTB). This is not consistent with other
>>>>>>> architectures, such as powerpc, which calls kmalloc() for allocating
>>>>>>> memory for the DTB.
>>>>>>>
>>>>>>> Call kmalloc() to allocate memory for the DTB, and kfree() to free
>>>>>>> the allocated memory.
>>>>>>>
>>>>>>> Co-developed-by: Prakhar Srivastava <[email protected]>
>>>>>>> Signed-off-by: Prakhar Srivastava <[email protected]>
>>>>>>> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
>>>>>>> ---
>>>>>>> arch/arm64/kernel/machine_kexec_file.c | 12 +++++++-----
>>>>>>> 1 file changed, 7 insertions(+), 5 deletions(-)
>>>>>>>
>>>>>>> diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
>>>>>>> index 7de9c47dee7c..51c40143d6fa 100644
>>>>>>> --- a/arch/arm64/kernel/machine_kexec_file.c
>>>>>>> +++ b/arch/arm64/kernel/machine_kexec_file.c
>>>>>>> @@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
>>>>>>> int arch_kimage_file_post_load_cleanup(struct kimage *image)
>>>>>>> {
>>>>>>> - vfree(image->arch.dtb);
>>>>>>> + kfree(image->arch.dtb);
>>>>>>> image->arch.dtb = NULL;
>>>>>>> vfree(image->arch.elf_headers);
>>>>>>> @@ -59,19 +59,21 @@ static int create_dtb(struct kimage *image,
>>>>>>> + cmdline_len + DTB_EXTRA_SPACE;
>>>>>>> for (;;) {
>>>>>>> - buf = vmalloc(buf_size);
>>>>>>> + buf = kmalloc(buf_size, GFP_KERNEL);
>>>>>>
>>>>>> Is there a functional need for this patch? I build the 'dtbs' target just
>>>>>> now and sdm845-db845c.dtb is approaching 100K, which feels quite large
>>>>>> for kmalloc().
>>>>>
>>>>> Changing the allocation from vmalloc() to kmalloc() would help us further
>>>>> consolidate the DTB setup code for powerpc and arm64.
>>>>
>>>> Ok, but at the risk of allocation failure. Can powerpc use vmalloc()
>>>> instead?
>>> I believe this patch stems from this suggestion by Rob Herring:
>>>
>>>> This could be taken a step further and do the allocation of the new
>>>> FDT. The difference is arm64 uses vmalloc and powerpc uses kmalloc. The
>>>> arm64 version also retries with a bigger allocation. That seems
>>>> unnecessary.
>>> in
>>> https://lore.kernel.org/linux-integrity/[email protected]/
>>> The problem is that this patch implements only part of the suggestion,
>>> which isn't useful in itself. So the patch series should either drop
>>> this patch or consolidate the FDT allocation between the arches.
>>> I just tested on powernv and pseries platforms and powerpc can use
>>> vmalloc for the FDT buffer.
>>>
>>
>> Thanks for verifying on powerpc platform Thiago.
>>
>> I'll update the patch to do the following:
>>
>> => Use vmalloc for FDT buffer allocation on powerpc
>> => Keep vmalloc for arm64, but remove the retry on allocation.
>> => Also, there was a memory leak of FDT buffer in the error code path on arm64,
>> which I'll fix as well.
>>
>> Did I miss anything?
>
> Yes, you missed the second part of Rob's suggestion I was mentioning,
> which is factoring out the code which allocates the new FDT from both
> arm64 and powerpc.
>

Sure - I'll address that.

thanks,
-lakshmi

2021-01-28 04:59:25

by Joe Perches

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer

On Thu, 2021-01-28 at 00:52 -0300, Thiago Jung Bauermann wrote:
> The problem is that this patch implements only part of the suggestion,
> which isn't useful in itself. So the patch series should either drop
> this patch or consolidate the FDT allocation between the arches.
>
> I just tested on powernv and pseries platforms and powerpc can use
> vmalloc for the FDT buffer.

Perhaps more sensible to use kvmalloc/kvfree.



2021-02-01 19:04:19

by Thiago Jung Bauermann

[permalink] [raw]
Subject: Re: [PATCH v15 09/10] arm64: Call kmalloc() to allocate DTB buffer


Joe Perches <[email protected]> writes:

> On Thu, 2021-01-28 at 00:52 -0300, Thiago Jung Bauermann wrote:
>> The problem is that this patch implements only part of the suggestion,
>> which isn't useful in itself. So the patch series should either drop
>> this patch or consolidate the FDT allocation between the arches.
>>
>> I just tested on powernv and pseries platforms and powerpc can use
>> vmalloc for the FDT buffer.
>
> Perhaps more sensible to use kvmalloc/kvfree.

That's true. Converting both arm64 to powerpc to kvmalloc/kvfree is a
good option. I don't think it's that much better though, because
kexec_file_load() is called infrequently and doesn't need to be fast so
the vmalloc() overhead isn't important in practice.

--
Thiago Jung Bauermann
IBM Linux Technology Center