[PATCH v2 8/8] kasan: test: avoid corrupting memory in kasan_rcu_uaf
From: andrey . konovalov
Date: Thu Aug 12 2021 - 11:05:51 EST
From: Andrey Konovalov <andreyknvl@xxxxxxxxx>
kasan_rcu_uaf() writes to freed memory via kasan_rcu_reclaim(), which is
only safe with the GENERIC mode (as it uses quarantine). For other modes,
this test corrupts kernel memory, which might result in a crash.
Turn the write into a read.
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxx>
---
lib/test_kasan_module.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/test_kasan_module.c b/lib/test_kasan_module.c
index fa73b9df0be4..7ebf433edef3 100644
--- a/lib/test_kasan_module.c
+++ b/lib/test_kasan_module.c
@@ -71,7 +71,7 @@ static noinline void __init kasan_rcu_reclaim(struct rcu_head *rp)
struct kasan_rcu_info, rcu);
kfree(fp);
- fp->i = 1;
+ ((volatile struct kasan_rcu_info *)fp)->i;
}
static noinline void __init kasan_rcu_uaf(void)
--
2.25.1