From: Amir Goldstein <amir73il@gmail.com> commit 4c37e71b713ecffe81f8e6273c6835e54306d412 upstream. The WARN_ON() that child entry is always on overlay st_dev became wrong when we allowed this function to update d_ino in non-samefs setup with xino enabled. It is not true in case of xino bits overflow on a non-dir inode. Leave the WARN_ON() only for directories, where assertion is still true. Fixes: adbf4f7ea834 ("ovl: consistent d_ino for non-samefs with xino") Cc: <stable@vger.kernel.org> # v4.17+ Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- fs/overlayfs/readdir.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c index cc8303a..11b7941 100644 --- a/fs/overlayfs/readdir.c +++ b/fs/overlayfs/readdir.c @@ -507,7 +507,13 @@ static int ovl_cache_update_ino(struct path *path, struct ovl_cache_entry *p) if (err) goto fail; - WARN_ON_ONCE(dir->d_sb->s_dev != stat.dev); + /* + * Directory inode is always on overlay st_dev. + * Non-dir with ovl_same_dev() could be on pseudo st_dev in case + * of xino bits overflow. + */ + WARN_ON_ONCE(S_ISDIR(stat.mode) && + dir->d_sb->s_dev != stat.dev); ino = stat.ino; } else if (xinobits && !OVL_TYPE_UPPER(type)) { ino = ovl_remap_lower_ino(ino, xinobits, -- 1.8.3