summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJan Kara <jack@suse.cz>2020-09-30 18:08:20 +0300
committerJan Kara <jack@suse.cz>2020-10-01 12:15:31 +0300
commitc2bb80b8bdd04dfe32364b78b61b6a47f717af52 (patch)
tree510e5996519092eb8aff43cd342207ae8dcb2f69
parent44ac6b829c4e173fdf6df18e6dd86aecf9a3dc99 (diff)
downloadlinux-c2bb80b8bdd04dfe32364b78b61b6a47f717af52.tar.xz
reiserfs: Fix oops during mount
With suitably crafted reiserfs image and mount command reiserfs will crash when trying to verify that XATTR_ROOT directory can be looked up in / as that recurses back to xattr code like: xattr_lookup+0x24/0x280 fs/reiserfs/xattr.c:395 reiserfs_xattr_get+0x89/0x540 fs/reiserfs/xattr.c:677 reiserfs_get_acl+0x63/0x690 fs/reiserfs/xattr_acl.c:209 get_acl+0x152/0x2e0 fs/posix_acl.c:141 check_acl fs/namei.c:277 [inline] acl_permission_check fs/namei.c:309 [inline] generic_permission+0x2ba/0x550 fs/namei.c:353 do_inode_permission fs/namei.c:398 [inline] inode_permission+0x234/0x4a0 fs/namei.c:463 lookup_one_len+0xa6/0x200 fs/namei.c:2557 reiserfs_lookup_privroot+0x85/0x1e0 fs/reiserfs/xattr.c:972 reiserfs_fill_super+0x2b51/0x3240 fs/reiserfs/super.c:2176 mount_bdev+0x24f/0x360 fs/super.c:1417 Fix the problem by bailing from reiserfs_xattr_get() when xattrs are not yet initialized. CC: stable@vger.kernel.org Reported-by: syzbot+9b33c9b118d77ff59b6f@syzkaller.appspotmail.com Signed-off-by: Jan Kara <jack@suse.cz>
-rw-r--r--fs/reiserfs/xattr.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
index 28b241cd6987..fe63a7c3e0da 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -674,6 +674,13 @@ reiserfs_xattr_get(struct inode *inode, const char *name, void *buffer,
if (get_inode_sd_version(inode) == STAT_DATA_V1)
return -EOPNOTSUPP;
+ /*
+ * priv_root needn't be initialized during mount so allow initial
+ * lookups to succeed.
+ */
+ if (!REISERFS_SB(inode->i_sb)->priv_root)
+ return 0;
+
dentry = xattr_lookup(inode, name, XATTR_REPLACE);
if (IS_ERR(dentry)) {
err = PTR_ERR(dentry);