diff mbox series

zram: fix potential UAF of zram table

Message ID 20250107065446.86928-1-ryncsn@gmail.com (mailing list archive)
State New
Headers show
Series zram: fix potential UAF of zram table | expand

Commit Message

Kairui Song Jan. 7, 2025, 6:54 a.m. UTC 
From: Kairui Song <kasong@tencent.com>

If zram_meta_alloc failed early, it frees allocated zram->table without
setting it NULL. Which will potentially cause zram_meta_free to access
the table if user reset an failed and uninitialized device.

Fixes: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device")
Cc: <stable@vger.kernel.org>
Signed-off-by: Kairui Song <kasong@tencent.com>
---
 drivers/block/zram/zram_drv.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Sergey Senozhatsky Jan. 7, 2025, 7:38 a.m. UTC | #1 
On (25/01/07 14:54), Kairui Song wrote:
> From: Kairui Song <kasong@tencent.com>
> 
> If zram_meta_alloc failed early, it frees allocated zram->table without
> setting it NULL. Which will potentially cause zram_meta_free to access
> the table if user reset an failed and uninitialized device.
> 
> Fixes: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device")
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Kairui Song <kasong@tencent.com>

Reviewed-by:  Sergey Senozhatsky <senozhatsky@chromium.org>
diff mbox series

Patch

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 5b8e4f4171ab..70ecaee25c20 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1465,6 +1465,7 @@  static bool zram_meta_alloc(struct zram *zram, u64 disksize)
 	zram->mem_pool = zs_create_pool(zram->disk->disk_name);
 	if (!zram->mem_pool) {
 		vfree(zram->table);
+		zram->table = NULL;
 		return false;
 	}