diff options
| author | Kees Cook <keescook@chromium.org> | 2021-04-02 01:23:47 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2021-04-08 14:05:20 +0200 |
| commit | 68ef8735d253f3d840082b78f996bf2d89ee6e5f (patch) | |
| tree | 56d0efc5657399b907ca874ddea2a8140c3976e9 /drivers/misc/lkdtm | |
| parent | x86/entry: Enable random_kstack_offset support (diff) | |
| download | linux-68ef8735d253f3d840082b78f996bf2d89ee6e5f.tar.xz linux-68ef8735d253f3d840082b78f996bf2d89ee6e5f.zip | |
lkdtm: Add REPORT_STACK for checking stack offsets
For validating the stack offset behavior, report the offset from a given
process's first seen stack address. Add s script to calculate the results
to the LKDTM kselftests.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210401232347.2791257-7-keescook@chromium.org
Diffstat (limited to 'drivers/misc/lkdtm')
| -rw-r--r-- | drivers/misc/lkdtm/bugs.c | 17 | ||||
| -rw-r--r-- | drivers/misc/lkdtm/core.c | 1 | ||||
| -rw-r--r-- | drivers/misc/lkdtm/lkdtm.h | 1 |
3 files changed, 19 insertions, 0 deletions
diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c index 110f5a8538e9..0e8254d0cf0b 100644 --- a/drivers/misc/lkdtm/bugs.c +++ b/drivers/misc/lkdtm/bugs.c @@ -134,6 +134,23 @@ noinline void lkdtm_CORRUPT_STACK_STRONG(void) __lkdtm_CORRUPT_STACK((void *)&data); } +static pid_t stack_pid; +static unsigned long stack_addr; + +void lkdtm_REPORT_STACK(void) +{ + volatile uintptr_t magic; + pid_t pid = task_pid_nr(current); + + if (pid != stack_pid) { + pr_info("Starting stack offset tracking for pid %d\n", pid); + stack_pid = pid; + stack_addr = (uintptr_t)&magic; + } + + pr_info("Stack offset: %d\n", (int)(stack_addr - (uintptr_t)&magic)); +} + void lkdtm_UNALIGNED_LOAD_STORE_WRITE(void) { static u8 data[5] __attribute__((aligned(4))) = {1, 2, 3, 4, 5}; diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c index b2aff4d87c01..8024b6a5cc7f 100644 --- a/drivers/misc/lkdtm/core.c +++ b/drivers/misc/lkdtm/core.c @@ -110,6 +110,7 @@ static const struct crashtype crashtypes[] = { CRASHTYPE(EXHAUST_STACK), CRASHTYPE(CORRUPT_STACK), CRASHTYPE(CORRUPT_STACK_STRONG), + CRASHTYPE(REPORT_STACK), CRASHTYPE(CORRUPT_LIST_ADD), CRASHTYPE(CORRUPT_LIST_DEL), CRASHTYPE(STACK_GUARD_PAGE_LEADING), diff --git a/drivers/misc/lkdtm/lkdtm.h b/drivers/misc/lkdtm/lkdtm.h index 5ae48c64df24..99f90d3e5e9c 100644 --- a/drivers/misc/lkdtm/lkdtm.h +++ b/drivers/misc/lkdtm/lkdtm.h @@ -17,6 +17,7 @@ void lkdtm_LOOP(void); void lkdtm_EXHAUST_STACK(void); void lkdtm_CORRUPT_STACK(void); void lkdtm_CORRUPT_STACK_STRONG(void); +void lkdtm_REPORT_STACK(void); void lkdtm_UNALIGNED_LOAD_STORE_WRITE(void); void lkdtm_SOFTLOCKUP(void); void lkdtm_HARDLOCKUP(void); |