| Message ID | 87bn7rtdwe.fsf@doppelsaurus.mobileactivedefense.com |
|---|---|
| State | Superseded, archived |
| Delegated to: | David Miller |
| Headers | show |
Hello. On 02/08/2016 06:33 PM, Rainer Weikusat wrote: > The present unix_stream_read_generic contains various code sequences of > the form > > err = -EDISASTER; > if (<test>) > goto out; > > This has the unfortunate side effect of possibly causing the error code > to bleed through to the final > > out: > return copied ? : err; > > and then to be wrongly returned if no data was copied because the caller > didn't supply a data buffer, as demonstrated by the program available at > > http://pad.lv/1540731 > > Change it such that err is only set if an error condition was detected. > > Fixes: 3822b5c2fc62 You also need to specify the patch summary like this: ("<summary"). > Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> [...] MBR, Sergei
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 49d5093..c1e4dd7 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -2277,13 +2277,15 @@ static int unix_stream_read_generic(struct unix_stream_read_state *state) size_t size = state->size; unsigned int last_len; - err = -EINVAL; - if (sk->sk_state != TCP_ESTABLISHED) + if (unlikely(sk->sk_state != TCP_ESTABLISHED)) { + err = -EINVAL; goto out; + } - err = -EOPNOTSUPP; - if (flags & MSG_OOB) + if (unlikely(flags & MSG_OOB)) { + err = -EOPNOTSUPP; goto out; + } target = sock_rcvlowat(sk, flags & MSG_WAITALL, size); timeo = sock_rcvtimeo(sk, noblock); @@ -2329,9 +2331,11 @@ again: goto unlock; unix_state_unlock(sk); - err = -EAGAIN; - if (!timeo) + if (!timeo) { + err = -EAGAIN; break; + } + mutex_unlock(&u->readlock); timeo = unix_stream_data_wait(sk, timeo, last,
The present unix_stream_read_generic contains various code sequences of the form err = -EDISASTER; if (<test>) goto out; This has the unfortunate side effect of possibly causing the error code to bleed through to the final out: return copied ? : err; and then to be wrongly returned if no data was copied because the caller didn't supply a data buffer, as demonstrated by the program available at http://pad.lv/1540731 Change it such that err is only set if an error condition was detected. Fixes: 3822b5c2fc62 Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> ---