From c15a77bdda2c4f8acaa3e436128630a81f904ae7 Mon Sep 17 00:00:00 2001 From: Willy Tarreau Date: Fri, 10 Jul 2020 15:23:19 +0200 Subject: [PATCH 01/10] random32: update the net random state on interrupt and activity 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 Suggested-by: Linus Torvalds Cc: Eric Dumazet Cc: "Jason A. Donenfeld" Cc: Andy Lutomirski Cc: Kees Cook Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Signed-off-by: Willy Tarreau Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- 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(-) diff --git a/drivers/char/random.c b/drivers/char/random.c index 8ff28c14af7e..e877c20e0ee0 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1330,6 +1330,7 @@ void add_interrupt_randomness(int irq, int irq_flags) 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) && diff --git a/include/linux/random.h b/include/linux/random.h index f189c927fdea..4d080e5ef6eb 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -9,6 +9,7 @@ #include #include +#include #include @@ -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); diff --git a/kernel/time/timer.c b/kernel/time/timer.c index 1e9b81a930c0..a3ae244b1bcd 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -43,6 +43,7 @@ #include #include #include +#include #include #include @@ -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); } /** diff --git a/lib/random32.c b/lib/random32.c index 763b920a6206..c4d317be2997 100644 --- a/lib/random32.c +++ b/lib/random32.c @@ -48,7 +48,7 @@ static inline void prandom_state_selftest(void) } #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 50bf89625bbaf6c29ba66a8b2b6faf80256a2466 Mon Sep 17 00:00:00 2001 From: Grygorii Strashko Date: Thu, 30 Jul 2020 22:05:01 +0300 Subject: [PATCH 02/10] ARM: percpu.h: fix build error MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- arch/arm/include/asm/percpu.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm/include/asm/percpu.h b/arch/arm/include/asm/percpu.h index f44f448537f2..1a3eedbac4a2 100644 --- 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 + /* * 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 7471f3228e7ad9641a8b2330960d27eb00af0d0f Mon Sep 17 00:00:00 2001 From: Willy Tarreau Date: Thu, 30 Jul 2020 07:59:24 +0200 Subject: [PATCH 03/10] random: fix circular include dependency on arm64 after addition of percpu.h MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 remove from the arm64 that causes the circular dependency. But we might as well do the whole belt-and-suspenders thing, and minimize inclusion in too. Either will fix the problem, and both are good changes. - Linus ] Reported-by: Daniel Díaz Reported-by: Kees Cook Tested-by: Marc Zyngier Fixes: f227e3ec3b5c Cc: Stephen Rothwell Signed-off-by: Willy Tarreau Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- include/linux/random.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/random.h b/include/linux/random.h index 4d080e5ef6eb..e5d63f875c02 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -9,7 +9,7 @@ #include #include -#include +#include #include From c131009987f2501642e3b3fa328ef6c65cbbc72a Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 29 Jul 2020 19:11:00 -0700 Subject: [PATCH 04/10] random32: remove net_rand_state from the latent entropy gcc plugin 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 Cc: Emese Revfy Cc: Kees Cook Cc: Willy Tarreau Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- include/linux/random.h | 2 +- lib/random32.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/random.h b/include/linux/random.h index e5d63f875c02..2625c0deda47 100644 --- 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); diff --git a/lib/random32.c b/lib/random32.c index c4d317be2997..3d749abb9e80 100644 --- a/lib/random32.c +++ b/lib/random32.c @@ -48,7 +48,7 @@ static inline void prandom_state_selftest(void) } #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. From f06d60ff794adeca67795dd12a8085cc921c4279 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 31 Jul 2020 07:51:14 +0200 Subject: [PATCH 05/10] random32: move the pseudo-random 32-bit definitions to prandom.h 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 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 , which can currently come in a lot of ways, including such fairly core headfers as . 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 Acked-by: Willy Tarreau Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- include/linux/prandom.h | 78 +++++++++++++++++++++++++++++++++++++++++ include/linux/random.h | 66 +++------------------------------- 2 files changed, 82 insertions(+), 62 deletions(-) create mode 100644 include/linux/prandom.h diff --git a/include/linux/prandom.h b/include/linux/prandom.h new file mode 100644 index 000000000000..aa16e6468f91 --- /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 +#include + +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 diff --git a/include/linux/random.h b/include/linux/random.h index 2625c0deda47..5b3ec7d2791f 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -9,7 +9,6 @@ #include #include -#include #include @@ -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 + * This is designed to be standalone for just prandom + * users, but for now we include it from + * for legacy reasons. */ -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); -} +#include #ifdef CONFIG_ARCH_RANDOM # include @@ -196,10 +144,4 @@ static inline bool arch_has_random_seed(void) } #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 6330b0cb2ace1d98ed4751c0cd131eddf1eb25b7 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 5 Aug 2020 12:10:44 +0100 Subject: [PATCH 06/10] arm64: Workaround circular dependency in pointer_auth.h MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Greg Kroah-Hartman --- arch/arm64/include/asm/pointer_auth.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/pointer_auth.h b/arch/arm64/include/asm/pointer_auth.h index 7a24bad1a58b..076a4157a74f 100644 --- 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 -#include #include #include @@ -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 + static inline void ptrauth_keys_init(struct ptrauth_keys *keys) { if (system_supports_address_auth()) { From c776104353550d4983ccc437aa40509f53b2227b Mon Sep 17 00:00:00 2001 From: Jiang Ying Date: Wed, 5 Aug 2020 15:57:21 +0800 Subject: [PATCH 07/10] ext4: fix direct I/O read error This patch is used to fix ext4 direct I/O read error when the read size is not aligned with block size. Then, I will use a test to explain the error. (1) Make a file that is not aligned with block size: $dd if=/dev/zero of=./test.jar bs=1000 count=3 (2) I wrote a source file named "direct_io_read_file.c" as following: #include #include #include #include #include #include #include #define BUF_SIZE 1024 int main() { int fd; int ret; unsigned char *buf; ret = posix_memalign((void **)&buf, 512, BUF_SIZE); if (ret) { perror("posix_memalign failed"); exit(1); } fd = open("./test.jar", O_RDONLY | O_DIRECT, 0755); if (fd < 0){ perror("open ./test.jar failed"); exit(1); } do { ret = read(fd, buf, BUF_SIZE); printf("ret=%d\n",ret); if (ret < 0) { perror("write test.jar failed"); } } while (ret > 0); free(buf); close(fd); } (3) Compile the source file: $gcc direct_io_read_file.c -D_GNU_SOURCE (4) Run the test program: $./a.out The result is as following: ret=1024 ret=1024 ret=952 ret=-1 write test.jar failed: Invalid argument. I have tested this program on XFS filesystem, XFS does not have this problem, because XFS use iomap_dio_rw() to do direct I/O read. And the comparing between read offset and file size is done in iomap_dio_rw(), the code is as following: if (pos < size) { retval = filemap_write_and_wait_range(mapping, pos, pos + iov_length(iov, nr_segs) - 1); if (!retval) { retval = mapping->a_ops->direct_IO(READ, iocb, iov, pos, nr_segs); } ... } ...only when "pos < size", direct I/O can be done, or 0 will be return. I have tested the fix patch on Ext4, it is up to the mustard of EINVAL in man2(read) as following: #include ssize_t read(int fd, void *buf, size_t count); EINVAL fd is attached to an object which is unsuitable for reading; or the file was opened with the O_DIRECT flag, and either the address specified in buf, the value specified in count, or the current file offset is not suitably aligned. So I think this patch can be applied to fix ext4 direct I/O error. However Ext4 introduces direct I/O read using iomap infrastructure on kernel 5.5, the patch is commit ("ext4: introduce direct I/O read using iomap infrastructure"), then Ext4 will be the same as XFS, they all use iomap_dio_rw() to do direct I/O read. So this problem does not exist on kernel 5.5 for Ext4. >From above description, we can see this problem exists on all the kernel versions between kernel 3.14 and kernel 5.4. It will cause the Applications to fail to read. For example, when the search service downloads a new full index file, the search engine is loading the previous index file and is processing the search request, it can not use buffer io that may squeeze the previous index file in use from pagecache, so the serch service must use direct I/O read. Please apply this patch on these kernel versions, or please use the method on kernel 5.5 to fix this problem. Fixes: 9fe55eea7e4b ("Fix race when checking i_size on direct i/o read") Reviewed-by: Jan Kara Co-developed-by: Wang Long Signed-off-by: Wang Long Signed-off-by: Jiang Ying Signed-off-by: Greg Kroah-Hartman --- fs/ext4/inode.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 7e0c77de551b..a284d99a1ee5 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3836,6 +3836,11 @@ static ssize_t ext4_direct_IO_read(struct kiocb *iocb, struct iov_iter *iter) struct inode *inode = mapping->host; size_t count = iov_iter_count(iter); ssize_t ret; + loff_t offset = iocb->ki_pos; + loff_t size = i_size_read(inode); + + if (offset >= size) + return 0; /* * Shared inode_lock is enough for us - it protects against concurrent From 9fe975acb53fa4c35bd8fd9c1ec6a47056659b46 Mon Sep 17 00:00:00 2001 From: Lorenz Bauer Date: Thu, 9 Jul 2020 12:51:51 +0100 Subject: [PATCH 08/10] selftests: bpf: Fix detach from sockmap tests 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 Signed-off-by: Lorenz Bauer Signed-off-by: Daniel Borkmann Reviewed-by: Jakub Sitnicki Link: https://lore.kernel.org/bpf/20200709115151.75829-1-lmb@cloudflare.com Signed-off-by: Greg Kroah-Hartman --- tools/testing/selftests/bpf/test_maps.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c index e1f1becda529..c812f0178b64 100644 --- 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 tasks, void *data) } 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 tasks, void *data) 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 ca7ace8fd26d9ae4be3cf69f474ddcfb0e8506ce Mon Sep 17 00:00:00 2001 From: Lorenz Bauer Date: Mon, 29 Jun 2020 10:56:28 +0100 Subject: [PATCH 09/10] bpf: sockmap: Require attach_bpf_fd when detaching a program 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 Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200629095630.7933-5-lmb@cloudflare.com Signed-off-by: Greg Kroah-Hartman --- 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(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 3bf3835d0e86..7aa0d8b5aaf0 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -956,11 +956,14 @@ static inline void bpf_map_offload_map_free(struct bpf_map *map) #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(const union bpf_attr *attr, { 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) diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h index 4bdb5e4bbd6a..20f3550b0b11 100644 --- a/include/linux/skmsg.h +++ b/include/linux/skmsg.h @@ -450,6 +450,19 @@ static inline void psock_set_prog(struct bpf_prog **pprog, 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); diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 8bc904f9badb..bf03d04a9e2f 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2029,10 +2029,10 @@ static int bpf_prog_detach(const union bpf_attr *attr) 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: diff --git a/net/core/sock_map.c b/net/core/sock_map.c index 6bbc118bf00e..df52061f99f7 100644 --- 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_attr *attr, struct bpf_prog *prog) 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_progs(struct bpf_map *map) } 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 d9939285fc818425ae92bd99f8c97b6b9ef3bb88 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Fri, 7 Aug 2020 09:34:02 +0200 Subject: [PATCH 10/10] Linux 5.4.57 Tested-by: Shuah Khan Signed-off-by: Greg Kroah-Hartman --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index c33fb4eebd4d..dd753ef637fd 100644 --- a/Makefile +++ b/Makefile @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 VERSION = 5 PATCHLEVEL = 4 -SUBLEVEL = 56 +SUBLEVEL = 57 EXTRAVERSION = NAME = Kleptomaniac Octopus