zram: fix potential UAF of zram table

BugLink: https://bugs.launchpad.net/bugs/2102266

commit 212fe1c0df4a150fb6298db2cfff267ceaba5402 upstream.

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.

Link: https://lkml.kernel.org/r/20250107065446.86928-1-ryncsn@gmail.com
Fixes: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device")
Signed-off-by: Kairui Song <kasong@tencent.com>
Reviewed-by:  Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 571d3f6045cd3a6d9f6aec33b678f3ffe97582ef linux-6.6.y)
[koichiroden: follow-up fix from v6.6.70]
Signed-off-by: Koichiro Den <koichiro.den@canonical.com>
Signed-off-by: Mehmet Basaran <mehmet.basaran@canonical.com>

This commit is contained in:

Kairui Song

2025-03-14 12:03:09 +09:00

committed by

Mehmet Basaran

parent 56d811eb25

commit e62ddebbde

1 changed files with 1 additions and 0 deletions

									
										drivers/block/zram/zram_drv.c
									
		+1
		
												View File
												
				@@ -1266,6 +1266,7 @@ 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;

					}