From: Al Viro Date: Sun, 6 May 2018 16:15:20 +0000 (-0400) Subject: affs_lookup(): close a race with affs_remove_link() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=30da870ce4a4e007c901858a96e9e394a1daa74a;p=linux.git affs_lookup(): close a race with affs_remove_link() we unlock the directory hash too early - if we are looking at secondary link and primary (in another directory) gets removed just as we unlock, we could have the old primary moved in place of the secondary, leaving us to look into freed entry (and leaving our dentry with ->d_fsdata pointing to a freed entry). Cc: stable@vger.kernel.org # 2.4.4+ Acked-by: David Sterba Signed-off-by: Al Viro --- diff --git a/fs/affs/namei.c b/fs/affs/namei.c index d8aa0ae3d037c..1ed0fa4c4d481 100644 --- a/fs/affs/namei.c +++ b/fs/affs/namei.c @@ -206,9 +206,10 @@ affs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) affs_lock_dir(dir); bh = affs_find_entry(dir, dentry); - affs_unlock_dir(dir); - if (IS_ERR(bh)) + if (IS_ERR(bh)) { + affs_unlock_dir(dir); return ERR_CAST(bh); + } if (bh) { u32 ino = bh->b_blocknr; @@ -222,10 +223,13 @@ affs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) } affs_brelse(bh); inode = affs_iget(sb, ino); - if (IS_ERR(inode)) + if (IS_ERR(inode)) { + affs_unlock_dir(dir); return ERR_CAST(inode); + } } d_add(dentry, inode); + affs_unlock_dir(dir); return NULL; }