@@ -1000,27 +1000,19 @@ static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
dentry = kern_path_create(AT_FDCWD, addr->name->sun_path, &parent, 0);
if (IS_ERR(dentry))
return PTR_ERR(dentry);
-
/*
* All right, let's create it.
*/
err = security_path_mknod(&parent, dentry, mode, 0);
if (!err)
err = vfs_mknod(d_inode(parent.dentry), dentry, mode, 0);
- if (err) {
- done_path_create(&parent, dentry);
- return err;
- }
+ if (err)
+ goto out;
err = mutex_lock_interruptible(&u->bindlock);
- if (err) {
- done_path_create(&parent, dentry);
- return err;
- }
- if (u->addr) {
- mutex_unlock(&u->bindlock);
- done_path_create(&parent, dentry);
- return -EINVAL;
- }
+ if (err)
+ goto out_unlink;
+ if (u->addr)
+ goto out_unlock;
addr->hash = UNIX_HASH_SIZE;
hash = d_backing_inode(dentry)->i_ino & (UNIX_HASH_SIZE - 1);
@@ -1032,6 +1024,16 @@ static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
mutex_unlock(&u->bindlock);
done_path_create(&parent, dentry);
return 0;
+
+out_unlock:
+ mutex_unlock(&u->bindlock);
+ err = -EINVAL;
+out_unlink:
+ /* failed after successful mknod? unlink what we'd created... */
+ vfs_unlink(d_inode(parent.dentry), dentry, NULL);
+out:
+ done_path_create(&parent, dentry);
+ return err;
}
static int unix_bind_abstract(struct sock *sk, unsigned hash,
We can do that more or less safely, since the parent is held locked all along. Yes, somebody might observe the object via dcache, only to have it disappear afterwards, but there's really no good way to prevent that. It won't race with other bind(2) or attempts to move the sucker elsewhere, or put something else in its place - locked parent prevents that. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> --- net/unix/af_unix.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-)