From 6889ee5a53b8d969aa542047f5ac8acdc0e79a91 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Fri, 6 Dec 2019 08:33:36 +0200 Subject: ovl: relax WARN_ON() on rename to self In ovl_rename(), if new upper is hardlinked to old upper underneath overlayfs before upper dirs are locked, user will get an ESTALE error and a WARN_ON will be printed. Changes to underlying layers while overlayfs is mounted may result in unexpected behavior, but it shouldn't crash the kernel and it shouldn't trigger WARN_ON() either, so relax this WARN_ON(). Reported-by: syzbot+bb1836a212e69f8e201a@syzkaller.appspotmail.com Fixes: 804032fabb3b ("ovl: don't check rename to self") Cc: # v4.9+ Signed-off-by: Amir Goldstein Signed-off-by: Miklos Szeredi --- fs/overlayfs/dir.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/overlayfs/dir.c') diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index 702aa63f6774..29abdb1d3b5c 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -1170,7 +1170,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, if (newdentry == trap) goto out_dput; - if (WARN_ON(olddentry->d_inode == newdentry->d_inode)) + if (olddentry->d_inode == newdentry->d_inode) goto out_dput; err = 0; -- cgit v1.2.3