From: Aaron Conole <aconole@xxxxxxxxxx> 3.12-stable review patch. If anyone has any objections, please let me know. =============== [ Upstream commit 9f389e35674f5b086edd70ed524ca0f287259725 ] AF_UNIX sockets now return multiple skbs from recv() when MSG_PEEK flag is set. This is referenced in kernel bugzilla #12323 @ https://bugzilla.kernel.org/show_bug.cgi?id=12323 As described both in the BZ and lkml thread @ http://lkml.org/lkml/2008/1/8/444 calling recv() with MSG_PEEK on an AF_UNIX socket only reads a single skb, where the desired effect is to return as much skb data has been queued, until hitting the recv buffer size (whichever comes first). The modified MSG_PEEK path will now move to the next skb in the tree and jump to the again: label, rather than following the natural loop structure. This requires duplicating some of the loop head actions. This was tested using the python socketpair python code attached to the bugzilla issue. Signed-off-by: Aaron Conole <aconole@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> --- net/unix/af_unix.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 9afa362d8a31..39b9429c2c86 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -2062,8 +2062,20 @@ again: if (UNIXCB(skb).fp) siocb->scm->fp = scm_fp_dup(UNIXCB(skb).fp); - sk_peek_offset_fwd(sk, chunk); + if (skip) { + sk_peek_offset_fwd(sk, chunk); + skip -= chunk; + } + + if (UNIXCB(skb).fp) + break; + last = skb; + unix_state_lock(sk); + skb = skb_peek_next(skb, &sk->sk_receive_queue); + if (skb) + goto again; + unix_state_unlock(sk); break; } } while (size); -- 2.6.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html