This is the start of the stable review cycle for the 5.4.57 release.
There are 9 patches in this series, all will be posted as a response
to this one. If anyone has any issues with these being applied, please
let me know.
Responses should be made by Fri, 07 Aug 2020 15:34:53 +0000.
Anything received after that time might be too late.
The whole patch series can be found in one patch at:
https://www.kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.4.57-rc1.gz
or in the git tree and branch at:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-5.4.y
and the diffstat can be found below.
thanks,
greg k-h
-------------
Pseudo-Shortlog of commits:
Greg Kroah-Hartman <[email protected]>
Linux 5.4.57-rc1
Lorenz Bauer <[email protected]>
bpf: sockmap: Require attach_bpf_fd when detaching a program
Lorenz Bauer <[email protected]>
selftests: bpf: Fix detach from sockmap tests
Jiang Ying <[email protected]>
ext4: fix direct I/O read error
Marc Zyngier <[email protected]>
arm64: Workaround circular dependency in pointer_auth.h
Linus Torvalds <[email protected]>
random32: move the pseudo-random 32-bit definitions to prandom.h
Linus Torvalds <[email protected]>
random32: remove net_rand_state from the latent entropy gcc plugin
Willy Tarreau <[email protected]>
random: fix circular include dependency on arm64 after addition of percpu.h
Grygorii Strashko <[email protected]>
ARM: percpu.h: fix build error
Willy Tarreau <[email protected]>
random32: update the net random state on interrupt and activity
-------------
Diffstat:
Makefile | 4 +-
arch/arm/include/asm/percpu.h | 2 +
arch/arm64/include/asm/pointer_auth.h | 8 +++-
drivers/char/random.c | 1 +
fs/ext4/inode.c | 5 +++
include/linux/bpf.h | 13 +++++-
include/linux/prandom.h | 78 +++++++++++++++++++++++++++++++++
include/linux/random.h | 63 ++------------------------
include/linux/skmsg.h | 13 ++++++
kernel/bpf/syscall.c | 4 +-
kernel/time/timer.c | 8 ++++
lib/random32.c | 2 +-
net/core/sock_map.c | 50 ++++++++++++++++++---
tools/testing/selftests/bpf/test_maps.c | 12 ++---
14 files changed, 185 insertions(+), 78 deletions(-)
From: Lorenz Bauer <[email protected]>
commit bb0de3131f4c60a9bf976681e0fe4d1e55c7a821 upstream.
The sockmap code currently ignores the value of attach_bpf_fd when
detaching a program. This is contrary to the usual behaviour of
checking that attach_bpf_fd represents the currently attached
program.
Ensure that attach_bpf_fd is indeed the currently attached
program. It turns out that all sockmap selftests already do this,
which indicates that this is unlikely to cause breakage.
Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Lorenz Bauer <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
include/linux/bpf.h | 13 +++++++++++--
include/linux/skmsg.h | 13 +++++++++++++
kernel/bpf/syscall.c | 4 ++--
net/core/sock_map.c | 50 +++++++++++++++++++++++++++++++++++++++++++++-----
4 files changed, 71 insertions(+), 9 deletions(-)
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -956,11 +956,14 @@ static inline void bpf_map_offload_map_f
#endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */
#if defined(CONFIG_BPF_STREAM_PARSER)
-int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog, u32 which);
+int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
+ struct bpf_prog *old, u32 which);
int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog);
+int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype);
#else
static inline int sock_map_prog_update(struct bpf_map *map,
- struct bpf_prog *prog, u32 which)
+ struct bpf_prog *prog,
+ struct bpf_prog *old, u32 which)
{
return -EOPNOTSUPP;
}
@@ -970,6 +973,12 @@ static inline int sock_map_get_from_fd(c
{
return -EINVAL;
}
+
+static inline int sock_map_prog_detach(const union bpf_attr *attr,
+ enum bpf_prog_type ptype)
+{
+ return -EOPNOTSUPP;
+}
#endif
#if defined(CONFIG_XDP_SOCKETS)
--- a/include/linux/skmsg.h
+++ b/include/linux/skmsg.h
@@ -450,6 +450,19 @@ static inline void psock_set_prog(struct
bpf_prog_put(prog);
}
+static inline int psock_replace_prog(struct bpf_prog **pprog,
+ struct bpf_prog *prog,
+ struct bpf_prog *old)
+{
+ if (cmpxchg(pprog, old, prog) != old)
+ return -ENOENT;
+
+ if (old)
+ bpf_prog_put(old);
+
+ return 0;
+}
+
static inline void psock_progs_drop(struct sk_psock_progs *progs)
{
psock_set_prog(&progs->msg_parser, NULL);
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -2029,10 +2029,10 @@ static int bpf_prog_detach(const union b
ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
break;
case BPF_SK_MSG_VERDICT:
- return sock_map_get_from_fd(attr, NULL);
+ return sock_map_prog_detach(attr, BPF_PROG_TYPE_SK_MSG);
case BPF_SK_SKB_STREAM_PARSER:
case BPF_SK_SKB_STREAM_VERDICT:
- return sock_map_get_from_fd(attr, NULL);
+ return sock_map_prog_detach(attr, BPF_PROG_TYPE_SK_SKB);
case BPF_LIRC_MODE2:
return lirc_prog_detach(attr);
case BPF_FLOW_DISSECTOR:
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -71,7 +71,42 @@ int sock_map_get_from_fd(const union bpf
map = __bpf_map_get(f);
if (IS_ERR(map))
return PTR_ERR(map);
- ret = sock_map_prog_update(map, prog, attr->attach_type);
+ ret = sock_map_prog_update(map, prog, NULL, attr->attach_type);
+ fdput(f);
+ return ret;
+}
+
+int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype)
+{
+ u32 ufd = attr->target_fd;
+ struct bpf_prog *prog;
+ struct bpf_map *map;
+ struct fd f;
+ int ret;
+
+ if (attr->attach_flags)
+ return -EINVAL;
+
+ f = fdget(ufd);
+ map = __bpf_map_get(f);
+ if (IS_ERR(map))
+ return PTR_ERR(map);
+
+ prog = bpf_prog_get(attr->attach_bpf_fd);
+ if (IS_ERR(prog)) {
+ ret = PTR_ERR(prog);
+ goto put_map;
+ }
+
+ if (prog->type != ptype) {
+ ret = -EINVAL;
+ goto put_prog;
+ }
+
+ ret = sock_map_prog_update(map, NULL, prog, attr->attach_type);
+put_prog:
+ bpf_prog_put(prog);
+put_map:
fdput(f);
return ret;
}
@@ -1015,27 +1050,32 @@ static struct sk_psock_progs *sock_map_p
}
int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
- u32 which)
+ struct bpf_prog *old, u32 which)
{
struct sk_psock_progs *progs = sock_map_progs(map);
+ struct bpf_prog **pprog;
if (!progs)
return -EOPNOTSUPP;
switch (which) {
case BPF_SK_MSG_VERDICT:
- psock_set_prog(&progs->msg_parser, prog);
+ pprog = &progs->msg_parser;
break;
case BPF_SK_SKB_STREAM_PARSER:
- psock_set_prog(&progs->skb_parser, prog);
+ pprog = &progs->skb_parser;
break;
case BPF_SK_SKB_STREAM_VERDICT:
- psock_set_prog(&progs->skb_verdict, prog);
+ pprog = &progs->skb_verdict;
break;
default:
return -EOPNOTSUPP;
}
+ if (old)
+ return psock_replace_prog(pprog, prog, old);
+
+ psock_set_prog(pprog, prog);
return 0;
}
From: Marc Zyngier <[email protected]>
With the backport of f227e3ec3b5c ("random32: update the net random
state on interrupt and activity") and its associated fixes, the
arm64 build explodes early:
In file included from ../include/linux/smp.h:67,
from ../include/linux/percpu.h:7,
from ../include/linux/prandom.h:12,
from ../include/linux/random.h:118,
from ../arch/arm64/include/asm/pointer_auth.h:6,
from ../arch/arm64/include/asm/processor.h:39,
from ../include/linux/mutex.h:19,
from ../include/linux/kernfs.h:12,
from ../include/linux/sysfs.h:16,
from ../include/linux/kobject.h:20,
from ../include/linux/of.h:17,
from ../include/linux/irqdomain.h:35,
from ../include/linux/acpi.h:13,
from ../include/acpi/apei.h:9,
from ../include/acpi/ghes.h:5,
from ../include/linux/arm_sdei.h:8,
from ../arch/arm64/kernel/asm-offsets.c:10:
../arch/arm64/include/asm/smp.h:100:29: error: field ‘ptrauth_key’ has
incomplete type
This is due to struct ptrauth_keys_kernel not being defined before
we transitively include asm/smp.h from linux/random.h.
Paper over it by moving the inclusion of linux/random.h *after* the
type has been defined.
Signed-off-by: Marc Zyngier <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
arch/arm64/include/asm/pointer_auth.h | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
--- a/arch/arm64/include/asm/pointer_auth.h
+++ b/arch/arm64/include/asm/pointer_auth.h
@@ -3,7 +3,6 @@
#define __ASM_POINTER_AUTH_H
#include <linux/bitops.h>
-#include <linux/random.h>
#include <asm/cpufeature.h>
#include <asm/memory.h>
@@ -30,6 +29,13 @@ struct ptrauth_keys {
struct ptrauth_key apga;
};
+/*
+ * Only include random.h once ptrauth_keys_* structures are defined
+ * to avoid yet another circular include hell (random.h * ends up
+ * including asm/smp.h, which requires ptrauth_keys_kernel).
+ */
+#include <linux/random.h>
+
static inline void ptrauth_keys_init(struct ptrauth_keys *keys)
{
if (system_supports_address_auth()) {
From: Grygorii Strashko <[email protected]>
commit aa54ea903abb02303bf55855fb51e3fcee135d70 upstream.
Fix build error for the case:
defined(CONFIG_SMP) && !defined(CONFIG_CPU_V6)
config: keystone_defconfig
CC arch/arm/kernel/signal.o
In file included from ../include/linux/random.h:14,
from ../arch/arm/kernel/signal.c:8:
../arch/arm/include/asm/percpu.h: In function ‘__my_cpu_offset’:
../arch/arm/include/asm/percpu.h:29:34: error: ‘current_stack_pointer’ undeclared (first use in this function); did you mean ‘user_stack_pointer’?
: "Q" (*(const unsigned long *)current_stack_pointer));
^~~~~~~~~~~~~~~~~~~~~
user_stack_pointer
Fixes: f227e3ec3b5c ("random32: update the net random state on interrupt and activity")
Signed-off-by: Grygorii Strashko <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
arch/arm/include/asm/percpu.h | 2 ++
1 file changed, 2 insertions(+)
--- a/arch/arm/include/asm/percpu.h
+++ b/arch/arm/include/asm/percpu.h
@@ -5,6 +5,8 @@
#ifndef _ASM_ARM_PERCPU_H_
#define _ASM_ARM_PERCPU_H_
+#include <asm/thread_info.h>
+
/*
* Same as asm-generic/percpu.h, except that we store the per cpu offset
* in the TPIDRPRW. TPIDRPRW only exists on V6K and V7
From: Willy Tarreau <[email protected]>
commit 1c9df907da83812e4f33b59d3d142c864d9da57f upstream.
Daniel Díaz and Kees Cook independently reported that commit
f227e3ec3b5c ("random32: update the net random state on interrupt and
activity") broke arm64 due to a circular dependency on include files
since the addition of percpu.h in random.h.
The correct fix would definitely be to move all the prandom32 stuff out
of random.h but for backporting, a smaller solution is preferred.
This one replaces linux/percpu.h with asm/percpu.h, and this fixes the
problem on x86_64, arm64, arm, and mips. Note that moving percpu.h
around didn't change anything and that removing it entirely broke
differently. When backporting, such options might still be considered
if this patch fails to help.
[ It turns out that an alternate fix seems to be to just remove the
troublesome <asm/pointer_auth.h> remove from the arm64 <asm/smp.h>
that causes the circular dependency.
But we might as well do the whole belt-and-suspenders thing, and
minimize inclusion in <linux/random.h> too. Either will fix the
problem, and both are good changes. - Linus ]
Reported-by: Daniel Díaz <[email protected]>
Reported-by: Kees Cook <[email protected]>
Tested-by: Marc Zyngier <[email protected]>
Fixes: f227e3ec3b5c
Cc: Stephen Rothwell <[email protected]>
Signed-off-by: Willy Tarreau <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
include/linux/random.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -9,7 +9,7 @@
#include <linux/list.h>
#include <linux/once.h>
-#include <linux/percpu.h>
+#include <asm/percpu.h>
#include <uapi/linux/random.h>
From: Lorenz Bauer <[email protected]>
commit f43cb0d672aa8eb09bfdb779de5900c040487d1d upstream.
Fix sockmap tests which rely on old bpf_prog_dispatch behaviour.
In the first case, the tests check that detaching without giving
a program succeeds. Since these are not the desired semantics,
invert the condition. In the second case, the clean up code doesn't
supply the necessary program fds.
Fixes: bb0de3131f4c ("bpf: sockmap: Require attach_bpf_fd when detaching a program")
Reported-by: Martin KaFai Lau <[email protected]>
Signed-off-by: Lorenz Bauer <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Reviewed-by: Jakub Sitnicki <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
tools/testing/selftests/bpf/test_maps.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -793,19 +793,19 @@ static void test_sockmap(unsigned int ta
}
err = bpf_prog_detach(fd, BPF_SK_SKB_STREAM_PARSER);
- if (err) {
+ if (!err) {
printf("Failed empty parser prog detach\n");
goto out_sockmap;
}
err = bpf_prog_detach(fd, BPF_SK_SKB_STREAM_VERDICT);
- if (err) {
+ if (!err) {
printf("Failed empty verdict prog detach\n");
goto out_sockmap;
}
err = bpf_prog_detach(fd, BPF_SK_MSG_VERDICT);
- if (err) {
+ if (!err) {
printf("Failed empty msg verdict prog detach\n");
goto out_sockmap;
}
@@ -1094,19 +1094,19 @@ static void test_sockmap(unsigned int ta
assert(status == 0);
}
- err = bpf_prog_detach(map_fd_rx, __MAX_BPF_ATTACH_TYPE);
+ err = bpf_prog_detach2(parse_prog, map_fd_rx, __MAX_BPF_ATTACH_TYPE);
if (!err) {
printf("Detached an invalid prog type.\n");
goto out_sockmap;
}
- err = bpf_prog_detach(map_fd_rx, BPF_SK_SKB_STREAM_PARSER);
+ err = bpf_prog_detach2(parse_prog, map_fd_rx, BPF_SK_SKB_STREAM_PARSER);
if (err) {
printf("Failed parser prog detach\n");
goto out_sockmap;
}
- err = bpf_prog_detach(map_fd_rx, BPF_SK_SKB_STREAM_VERDICT);
+ err = bpf_prog_detach2(verdict_prog, map_fd_rx, BPF_SK_SKB_STREAM_VERDICT);
if (err) {
printf("Failed parser prog detach\n");
goto out_sockmap;
From: Linus Torvalds <[email protected]>
commit c0842fbc1b18c7a044e6ff3e8fa78bfa822c7d1a upstream.
The addition of percpu.h to the list of includes in random.h revealed
some circular dependencies on arm64 and possibly other platforms. This
include was added solely for the pseudo-random definitions, which have
nothing to do with the rest of the definitions in this file but are
still there for legacy reasons.
This patch moves the pseudo-random parts to linux/prandom.h and the
percpu.h include with it, which is now guarded by _LINUX_PRANDOM_H and
protected against recursive inclusion.
A further cleanup step would be to remove this from <linux/random.h>
entirely, and make people who use the prandom infrastructure include
just the new header file. That's a bit of a churn patch, but grepping
for "prandom_" and "next_pseudo_random32" "struct rnd_state" should
catch most users.
But it turns out that that nice cleanup step is fairly painful, because
a _lot_ of code currently seems to depend on the implicit include of
<linux/random.h>, which can currently come in a lot of ways, including
such fairly core headfers as <linux/net.h>.
So the "nice cleanup" part may or may never happen.
Fixes: 1c9df907da83 ("random: fix circular include dependency on arm64 after addition of percpu.h")
Tested-by: Guenter Roeck <[email protected]>
Acked-by: Willy Tarreau <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
include/linux/prandom.h | 78 ++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/random.h | 66 ++--------------------------------------
2 files changed, 82 insertions(+), 62 deletions(-)
--- /dev/null
+++ b/include/linux/prandom.h
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * include/linux/prandom.h
+ *
+ * Include file for the fast pseudo-random 32-bit
+ * generation.
+ */
+#ifndef _LINUX_PRANDOM_H
+#define _LINUX_PRANDOM_H
+
+#include <linux/types.h>
+#include <linux/percpu.h>
+
+u32 prandom_u32(void);
+void prandom_bytes(void *buf, size_t nbytes);
+void prandom_seed(u32 seed);
+void prandom_reseed_late(void);
+
+struct rnd_state {
+ __u32 s1, s2, s3, s4;
+};
+
+DECLARE_PER_CPU(struct rnd_state, net_rand_state);
+
+u32 prandom_u32_state(struct rnd_state *state);
+void prandom_bytes_state(struct rnd_state *state, void *buf, size_t nbytes);
+void prandom_seed_full_state(struct rnd_state __percpu *pcpu_state);
+
+#define prandom_init_once(pcpu_state) \
+ DO_ONCE(prandom_seed_full_state, (pcpu_state))
+
+/**
+ * prandom_u32_max - returns a pseudo-random number in interval [0, ep_ro)
+ * @ep_ro: right open interval endpoint
+ *
+ * Returns a pseudo-random number that is in interval [0, ep_ro). Note
+ * that the result depends on PRNG being well distributed in [0, ~0U]
+ * u32 space. Here we use maximally equidistributed combined Tausworthe
+ * generator, that is, prandom_u32(). This is useful when requesting a
+ * random index of an array containing ep_ro elements, for example.
+ *
+ * Returns: pseudo-random number in interval [0, ep_ro)
+ */
+static inline u32 prandom_u32_max(u32 ep_ro)
+{
+ return (u32)(((u64) prandom_u32() * ep_ro) >> 32);
+}
+
+/*
+ * Handle minimum values for seeds
+ */
+static inline u32 __seed(u32 x, u32 m)
+{
+ return (x < m) ? x + m : x;
+}
+
+/**
+ * prandom_seed_state - set seed for prandom_u32_state().
+ * @state: pointer to state structure to receive the seed.
+ * @seed: arbitrary 64-bit value to use as a seed.
+ */
+static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
+{
+ u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
+
+ state->s1 = __seed(i, 2U);
+ state->s2 = __seed(i, 8U);
+ state->s3 = __seed(i, 16U);
+ state->s4 = __seed(i, 128U);
+}
+
+/* Pseudo random number generator from numerical recipes. */
+static inline u32 next_pseudo_random32(u32 seed)
+{
+ return seed * 1664525 + 1013904223;
+}
+
+#endif
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -9,7 +9,6 @@
#include <linux/list.h>
#include <linux/once.h>
-#include <asm/percpu.h>
#include <uapi/linux/random.h>
@@ -109,63 +108,12 @@ declare_get_random_var_wait(long)
unsigned long randomize_page(unsigned long start, unsigned long range);
-u32 prandom_u32(void);
-void prandom_bytes(void *buf, size_t nbytes);
-void prandom_seed(u32 seed);
-void prandom_reseed_late(void);
-
-struct rnd_state {
- __u32 s1, s2, s3, s4;
-};
-
-DECLARE_PER_CPU(struct rnd_state, net_rand_state);
-
-u32 prandom_u32_state(struct rnd_state *state);
-void prandom_bytes_state(struct rnd_state *state, void *buf, size_t nbytes);
-void prandom_seed_full_state(struct rnd_state __percpu *pcpu_state);
-
-#define prandom_init_once(pcpu_state) \
- DO_ONCE(prandom_seed_full_state, (pcpu_state))
-
-/**
- * prandom_u32_max - returns a pseudo-random number in interval [0, ep_ro)
- * @ep_ro: right open interval endpoint
- *
- * Returns a pseudo-random number that is in interval [0, ep_ro). Note
- * that the result depends on PRNG being well distributed in [0, ~0U]
- * u32 space. Here we use maximally equidistributed combined Tausworthe
- * generator, that is, prandom_u32(). This is useful when requesting a
- * random index of an array containing ep_ro elements, for example.
- *
- * Returns: pseudo-random number in interval [0, ep_ro)
- */
-static inline u32 prandom_u32_max(u32 ep_ro)
-{
- return (u32)(((u64) prandom_u32() * ep_ro) >> 32);
-}
-
/*
- * Handle minimum values for seeds
- */
-static inline u32 __seed(u32 x, u32 m)
-{
- return (x < m) ? x + m : x;
-}
-
-/**
- * prandom_seed_state - set seed for prandom_u32_state().
- * @state: pointer to state structure to receive the seed.
- * @seed: arbitrary 64-bit value to use as a seed.
+ * This is designed to be standalone for just prandom
+ * users, but for now we include it from <linux/random.h>
+ * for legacy reasons.
*/
-static inline void prandom_seed_state(struct rnd_state *state, u64 seed)
-{
- u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
-
- state->s1 = __seed(i, 2U);
- state->s2 = __seed(i, 8U);
- state->s3 = __seed(i, 16U);
- state->s4 = __seed(i, 128U);
-}
+#include <linux/prandom.h>
#ifdef CONFIG_ARCH_RANDOM
# include <asm/archrandom.h>
@@ -196,10 +144,4 @@ static inline bool arch_has_random_seed(
}
#endif
-/* Pseudo random number generator from numerical recipes. */
-static inline u32 next_pseudo_random32(u32 seed)
-{
- return seed * 1664525 + 1013904223;
-}
-
#endif /* _LINUX_RANDOM_H */
From: Willy Tarreau <[email protected]>
commit f227e3ec3b5cad859ad15666874405e8c1bbc1d4 upstream.
This modifies the first 32 bits out of the 128 bits of a random CPU's
net_rand_state on interrupt or CPU activity to complicate remote
observations that could lead to guessing the network RNG's internal
state.
Note that depending on some network devices' interrupt rate moderation
or binding, this re-seeding might happen on every packet or even almost
never.
In addition, with NOHZ some CPUs might not even get timer interrupts,
leaving their local state rarely updated, while they are running
networked processes making use of the random state. For this reason, we
also perform this update in update_process_times() in order to at least
update the state when there is user or system activity, since it's the
only case we care about.
Reported-by: Amit Klein <[email protected]>
Suggested-by: Linus Torvalds <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: "Jason A. Donenfeld" <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: <[email protected]>
Signed-off-by: Willy Tarreau <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/char/random.c | 1 +
include/linux/random.h | 3 +++
kernel/time/timer.c | 8 ++++++++
lib/random32.c | 2 +-
4 files changed, 13 insertions(+), 1 deletion(-)
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1330,6 +1330,7 @@ void add_interrupt_randomness(int irq, i
fast_mix(fast_pool);
add_interrupt_bench(cycles);
+ this_cpu_add(net_rand_state.s1, fast_pool->pool[cycles & 3]);
if (unlikely(crng_init == 0)) {
if ((fast_pool->count >= 64) &&
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -9,6 +9,7 @@
#include <linux/list.h>
#include <linux/once.h>
+#include <linux/percpu.h>
#include <uapi/linux/random.h>
@@ -117,6 +118,8 @@ struct rnd_state {
__u32 s1, s2, s3, s4;
};
+DECLARE_PER_CPU(struct rnd_state, net_rand_state) __latent_entropy;
+
u32 prandom_u32_state(struct rnd_state *state);
void prandom_bytes_state(struct rnd_state *state, void *buf, size_t nbytes);
void prandom_seed_full_state(struct rnd_state __percpu *pcpu_state);
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -43,6 +43,7 @@
#include <linux/sched/debug.h>
#include <linux/slab.h>
#include <linux/compat.h>
+#include <linux/random.h>
#include <linux/uaccess.h>
#include <asm/unistd.h>
@@ -1742,6 +1743,13 @@ void update_process_times(int user_tick)
scheduler_tick();
if (IS_ENABLED(CONFIG_POSIX_TIMERS))
run_posix_cpu_timers();
+
+ /* The current CPU might make use of net randoms without receiving IRQs
+ * to renew them often enough. Let's update the net_rand_state from a
+ * non-constant value that's not affine to the number of calls to make
+ * sure it's updated when there's some activity (we don't care in idle).
+ */
+ this_cpu_add(net_rand_state.s1, rol32(jiffies, 24) + user_tick);
}
/**
--- a/lib/random32.c
+++ b/lib/random32.c
@@ -48,7 +48,7 @@ static inline void prandom_state_selftes
}
#endif
-static DEFINE_PER_CPU(struct rnd_state, net_rand_state) __latent_entropy;
+DEFINE_PER_CPU(struct rnd_state, net_rand_state) __latent_entropy;
/**
* prandom_u32_state - seeded pseudo-random number generator.
From: Linus Torvalds <[email protected]>
commit 83bdc7275e6206f560d247be856bceba3e1ed8f2 upstream.
It turns out that the plugin right now ends up being really unhappy
about the change from 'static' to 'extern' storage that happened in
commit f227e3ec3b5c ("random32: update the net random state on interrupt
and activity").
This is probably a trivial fix for the latent_entropy plugin, but for
now, just remove net_rand_state from the list of things the plugin
worries about.
Reported-by: Stephen Rothwell <[email protected]>
Cc: Emese Revfy <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Willy Tarreau <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
include/linux/random.h | 2 +-
lib/random32.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -118,7 +118,7 @@ struct rnd_state {
__u32 s1, s2, s3, s4;
};
-DECLARE_PER_CPU(struct rnd_state, net_rand_state) __latent_entropy;
+DECLARE_PER_CPU(struct rnd_state, net_rand_state);
u32 prandom_u32_state(struct rnd_state *state);
void prandom_bytes_state(struct rnd_state *state, void *buf, size_t nbytes);
--- a/lib/random32.c
+++ b/lib/random32.c
@@ -48,7 +48,7 @@ static inline void prandom_state_selftes
}
#endif
-DEFINE_PER_CPU(struct rnd_state, net_rand_state) __latent_entropy;
+DEFINE_PER_CPU(struct rnd_state, net_rand_state);
/**
* prandom_u32_state - seeded pseudo-random number generator.
On Wed, 5 Aug 2020 at 21:23, Greg Kroah-Hartman
<[email protected]> wrote:
>
> This is the start of the stable review cycle for the 5.4.57 release.
> There are 9 patches in this series, all will be posted as a response
> to this one. If anyone has any issues with these being applied, please
> let me know.
>
> Responses should be made by Fri, 07 Aug 2020 15:34:53 +0000.
> Anything received after that time might be too late.
>
> The whole patch series can be found in one patch at:
> https://www.kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.4.57-rc1.gz
> or in the git tree and branch at:
> git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-5.4.y
> and the diffstat can be found below.
>
> thanks,
>
> greg k-h
Results from Linaro’s test farm.
No regressions on arm64, arm, x86_64, and i386.
Summary
------------------------------------------------------------------------
kernel: 5.4.57-rc1
git repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
git branch: linux-5.4.y
git commit: 1c4819817cd892724f91e5d253eec5f746243602
git describe: v5.4.56-10-g1c4819817cd8
Test details: https://qa-reports.linaro.org/lkft/linux-stable-rc-5.4-oe/build/v5.4.56-10-g1c4819817cd8
No regressions (compared to build v5.4.55-87-g47b594b8993f)
No fixes (compared to build v5.4.55-87-g47b594b8993f)
Ran 35321 total tests in the following environments and test suites.
Environments
--------------
- dragonboard-410c
- hi6220-hikey
- i386
- juno-r2
- juno-r2-compat
- juno-r2-kasan
- nxp-ls2088
- qemu_arm
- qemu_arm64
- qemu_i386
- qemu_x86_64
- x15
- x86
- x86-kasan
Test Suites
-----------
* install-android-platform-tools-r2800
* kvm-unit-tests
* libhugetlbfs
* linux-log-parser
* ltp-cap_bounds-tests
* ltp-controllers-tests
* ltp-cpuhotplug-tests
* ltp-crypto-tests
* ltp-fcntl-locktests-tests
* ltp-filecaps-tests
* ltp-fs-tests
* ltp-fs_bind-tests
* ltp-fs_perms_simple-tests
* ltp-fsx-tests
* ltp-hugetlb-tests
* ltp-mm-tests
* ltp-nptl-tests
* ltp-pty-tests
* ltp-sched-tests
* ltp-securebits-tests
* v4l2-compliance
* ltp-dio-tests
* ltp-io-tests
* ltp-ipc-tests
* ltp-commands-tests
* ltp-containers-tests
* ltp-cve-tests
* ltp-math-tests
* ltp-open-posix-tests
* ltp-syscalls-tests
* network-basic-tests
* igt-gpu-tools
--
Linaro LKFT
https://lkft.linaro.org
On Wed, Aug 05, 2020 at 05:52:37PM +0200, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 5.4.57 release.
> There are 9 patches in this series, all will be posted as a response
> to this one. If anyone has any issues with these being applied, please
> let me know.
>
> Responses should be made by Fri, 07 Aug 2020 15:34:53 +0000.
> Anything received after that time might be too late.
>
Build results:
total: 157 pass: 157 fail: 0
Qemu test results:
total: 429 pass: 429 fail: 0
Guenter
On 8/5/20 9:52 AM, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 5.4.57 release.
> There are 9 patches in this series, all will be posted as a response
> to this one. If anyone has any issues with these being applied, please
> let me know.
>
> Responses should be made by Fri, 07 Aug 2020 15:34:53 +0000.
> Anything received after that time might be too late.
>
> The whole patch series can be found in one patch at:
> https://www.kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.4.57-rc1.gz
> or in the git tree and branch at:
> git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-5.4.y
> and the diffstat can be found below.
>
> thanks,
>
> greg k-h
>
Compiled and booted on my test system. No dmesg regressions.
Tested-by: Shuah Khan <[email protected]>
thanks,
-- Shuah