From 7ec4cdb321738d44ae5d405e7b6ac73dfbf99caa Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Mon, 25 Jul 2022 22:49:25 +0900 Subject: [PATCH] mtd: core: check partition before dereference syzbot is reporting NULL pointer dereference at mtd_check_of_node() [1], for mtdram test device (CONFIG_MTD_MTDRAM) is not partition. Link: https://syzkaller.appspot.com/bug?extid=fe013f55a2814a9e8cfd [1] Reported-by: syzbot Reported-by: kernel test robot Fixes: ad9b10d1eaada169 ("mtd: core: introduce of support for dynamic partitions") Signed-off-by: Tetsuo Handa CC: stable@vger.kernel.org Signed-off-by: Richard Weinberger --- drivers/mtd/mtdcore.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -602,6 +602,8 @@ static void mtd_check_of_node(struct mtd return; /* Check if a partitions node exist */ + if (!mtd_is_partition(mtd)) + return; parent = mtd_get_master(mtd); parent_dn = dev_of_node(&parent->dev); if (!parent_dn)