Re: [PATCH 3.2 08/67] af_unix: fix struct pid memory leak

From: Rainer Weikusat
Date: Tue Feb 23 2016 - 17:07:34 EST


Ben Hutchings <ben@xxxxxxxxxxxxxxx> writes:
> 3.2.78-rc1 review patch. If anyone has any objections, please let me know.
>
> ------------------
>
> From: Eric Dumazet <edumazet@xxxxxxxxxx>
>
> commit fa0dc04df259ba2df3ce1920e9690c7842f8fa4b upstream.

[...]

> Fixes: b3ca9b02b007 ("net: fix multithreaded signal handling in unix recv routines")

[...]

> net/unix/af_unix.c | 1 +
> 1 file changed, 1 insertion(+)
>
> --- a/net/unix/af_unix.c
> +++ b/net/unix/af_unix.c
> @@ -2100,6 +2100,7 @@ static int unix_stream_recvmsg(struct ki
>
> if (signal_pending(current)) {
> err = sock_intr_errno(timeo);
> + scm_destroy(siocb->scm);
> goto out;
> }

JFTR: The commit mentioned in the fixes is (just the relevant part)

@@ -1895,11 +1903,12 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,

timeo = unix_stream_data_wait(sk, timeo);

- if (signal_pending(current)) {
+ if (signal_pending(current)
+ || mutex_lock_interruptible(&u->readlock)) {
err = sock_intr_errno(timeo);
goto out;
}
- mutex_lock(&u->readlock);
+
continue;
unlock:
unix_state_unlock(sk);

This not only didn't add the block triggering the error but this change
isn't even part of the (version of) the function which was fixed
anymore.