From ef9a7867b25fb8f7ae12295365b19377ae4a2d22 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E7=8E=8B=E8=B4=87?= Date: Mon, 30 Aug 2021 18:28:01 +0800 Subject: [PATCH] net: fix NULL pointer reference in cipso_v4_doi_free [ Upstream commit 733c99ee8be9a1410287cdbb943887365e83b2d6 ] In netlbl_cipsov4_add_std() when 'doi_def->map.std' alloc failed, we sometime observe panic: BUG: kernel NULL pointer dereference, address: ... RIP: 0010:cipso_v4_doi_free+0x3a/0x80 ... Call Trace: netlbl_cipsov4_add_std+0xf4/0x8c0 netlbl_cipsov4_add+0x13f/0x1b0 genl_family_rcv_msg_doit.isra.15+0x132/0x170 genl_rcv_msg+0x125/0x240 This is because in cipso_v4_doi_free() there is no check on 'doi_def->map.std' when 'doi_def->type' equal 1, which is possibe, since netlbl_cipsov4_add_std() haven't initialize it before alloc 'doi_def->map.std'. This patch just add the check to prevent panic happen for similar cases. Reported-by: Abaci Signed-off-by: Michael Wang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/netlabel/netlabel_cipso_v4.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/netlabel/netlabel_cipso_v4.c b/net/netlabel/netlabel_cipso_v4.c index 8cd3daf0e3db..1778e4e8ce24 100644 --- a/net/netlabel/netlabel_cipso_v4.c +++ b/net/netlabel/netlabel_cipso_v4.c @@ -144,8 +144,8 @@ static int netlbl_cipsov4_add_std(struct genl_info *info, return -ENOMEM; doi_def->map.std = kzalloc(sizeof(*doi_def->map.std), GFP_KERNEL); if (doi_def->map.std == NULL) { - ret_val = -ENOMEM; - goto add_std_failure; + kfree(doi_def); + return -ENOMEM; } doi_def->type = CIPSO_V4_MAP_TRANS;