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() code attached to the bugzilla issue. Signed-off-by: Aaron Conole <acon...@bytheb.org> --- net/unix/af_unix.c | 17+- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 03ee4d3..d2fd342 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -2179,9 +2181,22 @@ unlock: if (UNIXCB(skb).fp) scm.fp = scm_fp_dup(UNIXCB(skb).fp); - sk_peek_offset_fwd(sk, chunk); + if (skip) + { + sk_peek_offset_fwd(sk, chunk); + skip -= chunk; + } - break; + if (UNIXCB(skb).fp) + break; + + /* XXX - this is ugly; better would be rewrite the function */ + last = skb; + last_len = skb->len; + unix_state_lock(&sk); + skb = skb_peek_next(skb, &sk->sk_receive_queue); + if (skb) goto again; + goto unlock; } } while (size); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
