From: Jia-Ju Bai baijiaju1990@gmail.com
[ Upstream commit 2abb7d3b12d007c30193f48bebed781009bebdd2 ]
In ocfs2_info_scan_inode_alloc(), there is an if statement on line 283 to check whether inode_alloc is NULL:
if (inode_alloc)
When inode_alloc is NULL, it is used on line 287:
ocfs2_inode_lock(inode_alloc, &bh, 0); ocfs2_inode_lock_full_nested(inode, ...) struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
Thus, a possible null-pointer dereference may occur.
To fix this bug, inode_alloc is checked on line 286.
This bug is found by a static analysis tool STCheck written by us.
Link: http://lkml.kernel.org/r/20190726033717.32359-1-baijiaju1990@gmail.com Signed-off-by: Jia-Ju Bai baijiaju1990@gmail.com Reviewed-by: Joseph Qi joseph.qi@linux.alibaba.com Cc: Mark Fasheh mark@fasheh.com Cc: Joel Becker jlbec@evilplan.org Cc: Junxiao Bi junxiao.bi@oracle.com Cc: Changwei Ge gechangwei@live.cn Cc: Gang He ghe@suse.com Cc: Jun Piao piaojun@huawei.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ocfs2/ioctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c index 4506ec5ec2ea6..bfc44644301ca 100644 --- a/fs/ocfs2/ioctl.c +++ b/fs/ocfs2/ioctl.c @@ -289,7 +289,7 @@ static int ocfs2_info_scan_inode_alloc(struct ocfs2_super *osb, if (inode_alloc) inode_lock(inode_alloc);
- if (o2info_coherent(&fi->ifi_req)) { + if (inode_alloc && o2info_coherent(&fi->ifi_req)) { status = ocfs2_inode_lock(inode_alloc, &bh, 0); if (status < 0) { mlog_errno(status);