2024-06-13 15:42:07

by Ilya Leoshkevich

[permalink] [raw]
Subject: [PATCH v4 05/35] kmsan: Fix is_bad_asm_addr() on arches with overlapping address spaces

Comparing pointers with TASK_SIZE does not make sense when kernel and
userspace overlap. Skip the comparison when this is the case.

Reviewed-by: Alexander Potapenko <[email protected]>
Signed-off-by: Ilya Leoshkevich <[email protected]>
---
mm/kmsan/instrumentation.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/kmsan/instrumentation.c b/mm/kmsan/instrumentation.c
index 470b0b4afcc4..8a1bbbc723ab 100644
--- a/mm/kmsan/instrumentation.c
+++ b/mm/kmsan/instrumentation.c
@@ -20,7 +20,8 @@

static inline bool is_bad_asm_addr(void *addr, uintptr_t size, bool is_store)
{
- if ((u64)addr < TASK_SIZE)
+ if (IS_ENABLED(CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE) &&
+ (u64)addr < TASK_SIZE)
return true;
if (!kmsan_get_metadata(addr, KMSAN_META_SHADOW))
return true;
--
2.45.1