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From: andrey.konovalov@linux.dev
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>,
	Marco Elver <elver@google.com>,
	Alexander Potapenko <glider@google.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	kasan-dev@googlegroups.com,
	linux-mm@kvack.org,
	Brad Spengler <spender@grsecurity.net>,
	linux-kernel@vger.kernel.org
Subject: [PATCH] kasan: fix bad call to unpoison_slab_object
Date: Fri, 14 Jun 2024 16:16:40 +0200
Message-Id: <20240614141640.59324-1-andrey.konovalov@linux.dev>
Precedence: bulk
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From: Andrey Konovalov <andreyknvl@gmail.com>

Commit 29d7355a9d05 ("kasan: save alloc stack traces for mempool") messed
up one of the calls to unpoison_slab_object: the last two arguments are
supposed to be GFP flags and whether to init the object memory.

Fix the call.

Without this fix, unpoison_slab_object provides the object's size as
GFP flags to unpoison_slab_object, which can cause LOCKDEP reports
(and probably other issues).

Fixes: 29d7355a9d05 ("kasan: save alloc stack traces for mempool")
Reported-by: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Andrey Konovalov <andreyknvl@gmail.com>
---
 mm/kasan/common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index e7c9a4dc89f8..85e7c6b4575c 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -532,7 +532,7 @@ void __kasan_mempool_unpoison_object(void *ptr, size_t size, unsigned long ip)
 		return;
 
 	/* Unpoison the object and save alloc info for non-kmalloc() allocations. */
-	unpoison_slab_object(slab->slab_cache, ptr, size, flags);
+	unpoison_slab_object(slab->slab_cache, ptr, flags, false);
 
 	/* Poison the redzone and save alloc info for kmalloc() allocations. */
 	if (is_kmalloc_cache(slab->slab_cache))
-- 
2.25.1