[PATCH 4.19 178/191] reiserfs: prevent NULL pointer dereference in reiserfs_insert_item()

From: Greg Kroah-Hartman
Date: Fri Feb 21 2020 - 03:24:20 EST

From: Yunfeng Ye <yeyunfeng@xxxxxxxxxx>

[ Upstream commit aacee5446a2a1aa35d0a49dab289552578657fb4 ]

The variable inode may be NULL in reiserfs_insert_item(), but there is
no check before accessing the member of inode.

Fix this by adding NULL pointer check before calling reiserfs_debug().

Link: http://lkml.kernel.org/r/79c5135d-ff25-1cc9-4e99-9f572b88cc00@xxxxxxxxxx
Signed-off-by: Yunfeng Ye <yeyunfeng@xxxxxxxxxx>
Cc: zhengbin <zhengbin13@xxxxxxxxxx>
Cc: Hu Shiyuan <hushiyuan@xxxxxxxxxx>
Cc: Feilong Lin <linfeilong@xxxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
fs/reiserfs/stree.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/reiserfs/stree.c b/fs/reiserfs/stree.c
index 0037aea97d39a..2946713cb00d6 100644
--- a/fs/reiserfs/stree.c
+++ b/fs/reiserfs/stree.c
@@ -2250,7 +2250,8 @@ error_out:
/* also releases the path */
- reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE,
+ if (inode)
+ reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE,
"reiserquota insert_item(): freeing %u id=%u type=%c",
quota_bytes, inode->i_uid, head2type(ih));