Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934263AbcKJO5y (ORCPT ); Thu, 10 Nov 2016 09:57:54 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:57926 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S934150AbcKJO5D (ORCPT ); Thu, 10 Nov 2016 09:57:03 -0500 From: Mimi Zohar To: linux-security-module Cc: Thiago Jung Bauermann , linux-ima-devel@lists.sourceforge.net, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Andrew Morton , Dmitry Kasatkin , Mimi Zohar Subject: [PATCHC v7 05/10] powerpc: ima: Send the kexec buffer to the next kernel Date: Thu, 10 Nov 2016 09:56:15 -0500 X-Mailer: git-send-email 2.1.0 In-Reply-To: <1478789780-17719-1-git-send-email-zohar@linux.vnet.ibm.com> References: <1478789780-17719-1-git-send-email-zohar@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16111014-0016-0000-0000-000001EF1880 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16111014-0017-0000-0000-000005D404F0 Message-Id: <1478789780-17719-6-git-send-email-zohar@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-11-10_07:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=2 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1609300000 definitions=main-1611100270 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8074 Lines: 247 From: Thiago Jung Bauermann The IMA kexec buffer allows the currently running kernel to pass the measurement list via a kexec segment to the kernel that will be kexec'd. This is the architecture-specific part of setting up the IMA kexec buffer for the next kernel. It will be used in the next patch. Changelog v5: - New patch in this version. This code was previously in the kexec buffer handover patch series. Changelog relative to kexec handover patches v5: - Moved code to arch/powerpc/kernel/ima_kexec.c. - Renamed functions and struct members to variations of ima_kexec_buffer instead of variations of kexec_handover_buffer. - Use a single property /chosen/linux,ima-kexec-buffer containing the buffer address and length, instead of /chosen/linux,kexec-handover-buffer-{start,end}. - Use #address-cells and #size-cells to write the DT property. - Use size_t instead of unsigned long for size arguments. - Use CONFIG_IMA_KEXEC to build this code only when necessary. Signed-off-by: Thiago Jung Bauermann Acked-by: "Eric W. Biederman" Signed-off-by: Mimi Zohar --- arch/powerpc/include/asm/ima.h | 16 +++++ arch/powerpc/include/asm/kexec.h | 14 ++++- arch/powerpc/kernel/ima_kexec.c | 91 +++++++++++++++++++++++++++++ arch/powerpc/kernel/kexec_elf_64.c | 2 +- arch/powerpc/kernel/machine_kexec_file_64.c | 12 +++- 5 files changed, 129 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h index d5a72dd9b499..2313bdface34 100644 --- a/arch/powerpc/include/asm/ima.h +++ b/arch/powerpc/include/asm/ima.h @@ -1,6 +1,8 @@ #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); @@ -10,4 +12,18 @@ void remove_ima_buffer(void *fdt, int chosen_node); 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, + 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 23056d2dc330..a49cab287acb 100644 --- a/arch/powerpc/include/asm/kexec.h +++ b/arch/powerpc/include/asm/kexec.h @@ -94,12 +94,22 @@ static inline bool kdump_in_progress(void) #ifdef CONFIG_KEXEC_FILE extern struct kexec_file_ops kexec_elf64_ops; +#ifdef CONFIG_IMA_KEXEC +#define ARCH_HAS_KIMAGE_ARCH + +struct kimage_arch { + phys_addr_t ima_buffer_addr; + size_t ima_buffer_size; +}; +#endif + int setup_purgatory(struct kimage *image, const void *slave_code, const void *fdt, unsigned long kernel_load_addr, unsigned long fdt_load_addr, unsigned long stack_top, int debug); -int setup_new_fdt(void *fdt, unsigned long initrd_load_addr, - unsigned long initrd_len, const char *cmdline); +int setup_new_fdt(const struct kimage *image, void *fdt, + unsigned long initrd_load_addr, unsigned long initrd_len, + const char *cmdline); bool find_debug_console(const void *fdt); int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size); #endif /* CONFIG_KEXEC_FILE */ diff --git a/arch/powerpc/kernel/ima_kexec.c b/arch/powerpc/kernel/ima_kexec.c index 36e5a5df3804..5ea42c937ca9 100644 --- a/arch/powerpc/kernel/ima_kexec.c +++ b/arch/powerpc/kernel/ima_kexec.c @@ -130,3 +130,94 @@ void remove_ima_buffer(void *fdt, int chosen_node) if (!ret) pr_debug("Removed old IMA buffer reservation.\n"); } + +#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) { + 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/arch/powerpc/kernel/kexec_elf_64.c b/arch/powerpc/kernel/kexec_elf_64.c index dc29e0131b76..1bd1e9865835 100644 --- a/arch/powerpc/kernel/kexec_elf_64.c +++ b/arch/powerpc/kernel/kexec_elf_64.c @@ -206,7 +206,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf, goto out; } - ret = setup_new_fdt(fdt, initrd_load_addr, initrd_len, cmdline); + ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline); if (ret) goto out; diff --git a/arch/powerpc/kernel/machine_kexec_file_64.c b/arch/powerpc/kernel/machine_kexec_file_64.c index 7b13634f71bf..e4da26dabbaf 100644 --- a/arch/powerpc/kernel/machine_kexec_file_64.c +++ b/arch/powerpc/kernel/machine_kexec_file_64.c @@ -393,6 +393,7 @@ int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size) /* * 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. @@ -401,8 +402,9 @@ int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size) * * Return: 0 on success, or negative errno on error. */ -int setup_new_fdt(void *fdt, unsigned long initrd_load_addr, - unsigned long initrd_len, const char *cmdline) +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; @@ -512,7 +514,11 @@ int setup_new_fdt(void *fdt, unsigned long initrd_load_addr, } } - remove_ima_buffer(fdt, chosen_node); + ret = setup_ima_buffer(image, fdt, chosen_node); + 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) { -- 2.1.0