diff options
| author | Catalin Marinas <catalin.marinas@arm.com> | 2010-02-08 11:16:24 +0000 |
|---|---|---|
| committer | Pekka Enberg <penberg@cs.helsinki.fi> | 2010-02-17 21:39:08 +0200 |
| commit | 81fc03909a80bead8f553287a2b749a1d29dca64 (patch) | |
| tree | 6c62a780be628ea551bf1e5854260ce94608c521 | |
| parent | 724e6d3fe8003c3f60bf404bf22e4e331327c596 (diff) | |
kmemcheck: Test the full object in kmemcheck_is_obj_initialized()
This is a fix for bug #14845 (bugzilla.kernel.org). The update_checksum()
function in mm/kmemleak.c calls kmemcheck_is_obj_initialised() before scanning
an object. When KMEMCHECK_PARTIAL_OK is enabled, this function returns true.
However, the crc32_le() reads smaller intervals (32-bit) for which
kmemleak_is_obj_initialised() may be false leading to a kmemcheck warning.
Note that kmemcheck_is_obj_initialized() is currently only used by
kmemleak before scanning a memory location.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christian Casteyde <casteyde.christian@free.fr>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
| -rw-r--r-- | arch/x86/mm/kmemcheck/kmemcheck.c | 2 | ||||
| -rw-r--r-- | arch/x86/mm/kmemcheck/shadow.c | 16 | ||||
| -rw-r--r-- | arch/x86/mm/kmemcheck/shadow.h | 2 |
3 files changed, 17 insertions, 3 deletions
diff --git a/arch/x86/mm/kmemcheck/kmemcheck.c b/arch/x86/mm/kmemcheck/kmemcheck.c index 8cc18334414..b3b531a4f8e 100644 --- a/arch/x86/mm/kmemcheck/kmemcheck.c +++ b/arch/x86/mm/kmemcheck/kmemcheck.c @@ -337,7 +337,7 @@ bool kmemcheck_is_obj_initialized(unsigned long addr, size_t size) if (!shadow) return true; - status = kmemcheck_shadow_test(shadow, size); + status = kmemcheck_shadow_test_all(shadow, size); return status == KMEMCHECK_SHADOW_INITIALIZED; } diff --git a/arch/x86/mm/kmemcheck/shadow.c b/arch/x86/mm/kmemcheck/shadow.c index 3f66b82076a..aec124214d9 100644 --- a/arch/x86/mm/kmemcheck/shadow.c +++ b/arch/x86/mm/kmemcheck/shadow.c @@ -125,12 +125,12 @@ void kmemcheck_mark_initialized_pages(struct page *p, unsigned int n) enum kmemcheck_shadow kmemcheck_shadow_test(void *shadow, unsigned int size) { +#ifdef CONFIG_KMEMCHECK_PARTIAL_OK uint8_t *x; unsigned int i; x = shadow; -#ifdef CONFIG_KMEMCHECK_PARTIAL_OK /* * Make sure _some_ bytes are initialized. Gcc frequently generates * code to access neighboring bytes. @@ -139,13 +139,25 @@ enum kmemcheck_shadow kmemcheck_shadow_test(void *shadow, unsigned int size) if (x[i] == KMEMCHECK_SHADOW_INITIALIZED) return x[i]; } + + return x[0]; #else + return kmemcheck_shadow_test_all(shadow, size); +#endif +} + +enum kmemcheck_shadow kmemcheck_shadow_test_all(void *shadow, unsigned int size) +{ + uint8_t *x; + unsigned int i; + + x = shadow; + /* All bytes must be initialized. */ for (i = 0; i < size; ++i) { if (x[i] != KMEMCHECK_SHADOW_INITIALIZED) return x[i]; } -#endif return x[0]; } diff --git a/arch/x86/mm/kmemcheck/shadow.h b/arch/x86/mm/kmemcheck/shadow.h index af46d9ab9d8..ff0b2f70fbc 100644 --- a/arch/x86/mm/kmemcheck/shadow.h +++ b/arch/x86/mm/kmemcheck/shadow.h @@ -11,6 +11,8 @@ enum kmemcheck_shadow { void *kmemcheck_shadow_lookup(unsigned long address); enum kmemcheck_shadow kmemcheck_shadow_test(void *shadow, unsigned int size); +enum kmemcheck_shadow kmemcheck_shadow_test_all(void *shadow, + unsigned int size); void kmemcheck_shadow_set(void *shadow, unsigned int size); #endif |