git: 47112d359b36 - main - kassert: Remove KASAN marking from DEBUG_POISON_POINTER

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=47112d359b36899893a386f572bd1a4ab007e8a2

commit 47112d359b36899893a386f572bd1a4ab007e8a2
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2024-09-14 01:32:06 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2024-09-14 01:34:12 +0000

    kassert: Remove KASAN marking from DEBUG_POISON_POINTER
    
    While this approach works for trapping reads of an uninitialized
    pointer, it means that any attempt to store to the variable triggers a
    KASAN report, which is not what we want.  Simply remove the kasan_mark()
    call.  KMSAN will catch these kinds of bugs automatically anyway.
    
    Reported by:    syzbot+c5e279db5763b58e8d69@syzkaller.appspotmail.com
    MFC after:      1 week
---
 sys/sys/kassert.h | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/sys/sys/kassert.h b/sys/sys/kassert.h
index ab2313bcbd8b..8dcea8352fdf 100644
--- a/sys/sys/kassert.h
+++ b/sys/sys/kassert.h
@@ -38,8 +38,7 @@ extern const char *panicstr;	/* panic message */
 #define	KERNEL_PANICKED()	__predict_false(panicstr != NULL)
 
 /*
- * Trap accesses going through a pointer. Moreover if kasan is available trap
- * reading the pointer itself.
+ * Trap accesses going through a pointer.
  *
  * Sample usage: you have a struct with numerous fields and by API contract
  * only some of them get populated, even if the implementation temporary writes
@@ -61,7 +60,6 @@ extern caddr_t poisoned_buf;
 
 #define DEBUG_POISON_POINTER(x) ({				\
 	x = (void *)(DEBUG_POISON_POINTER_VALUE);		\
-	kasan_mark(&x, 0, sizeof(x), KASAN_GENERIC_REDZONE);	\
 })
 
 #else