diff options
| author | Andreas Dilger <adilger@dilger.ca> | 2012-05-28 17:02:25 -0400 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2012-06-10 14:41:49 +0100 |
| commit | 7523a2de6d789ce1b8f5601f9305ccfa68924c3a (patch) | |
| tree | 48fb4fc8f50caae35efd843c182d4e3c0f6a14e7 | |
| parent | 3e9fc33800a233c2820abae8428fda5f5e508263 (diff) | |
ext4: disallow hard-linked directory in ext4_lookup
commit 7e936b737211e6b54e34b71a827e56b872e958d8 upstream.
A hard-linked directory to its parent can cause the VFS to deadlock,
and is a sign of a corrupted file system. So detect this case in
ext4_lookup(), before the rmdir() lockup scenario can take place.
Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | fs/ext4/namei.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index aa4c782c9dd7..4dd0890e9435 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1037,6 +1037,12 @@ static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, stru EXT4_ERROR_INODE(dir, "bad inode number: %u", ino); return ERR_PTR(-EIO); } + if (unlikely(ino == dir->i_ino)) { + EXT4_ERROR_INODE(dir, "'%.*s' linked to parent dir", + dentry->d_name.len, + dentry->d_name.name); + return ERR_PTR(-EIO); + } inode = ext4_iget(dir->i_sb, ino); if (inode == ERR_PTR(-ESTALE)) { EXT4_ERROR_INODE(dir, |