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| author | Jan Kara <jack@suse.cz> | 2020-09-30 17:08:20 +0200 |
|---|---|---|
| committer | Jan Kara <jack@suse.cz> | 2020-10-01 11:15:31 +0200 |
| commit | c2bb80b8bdd04dfe32364b78b61b6a47f717af52 (patch) | |
| tree | 510e5996519092eb8aff43cd342207ae8dcb2f69 /fs/reiserfs/xattr.c | |
| parent | 44ac6b829c4e173fdf6df18e6dd86aecf9a3dc99 (diff) | |
| download | lwn-c2bb80b8bdd04dfe32364b78b61b6a47f717af52.tar.gz lwn-c2bb80b8bdd04dfe32364b78b61b6a47f717af52.zip | |
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>
Diffstat (limited to 'fs/reiserfs/xattr.c')
| -rw-r--r-- | fs/reiserfs/xattr.c | 7 |
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); |