From 4613012db1d911f80897f9446a49de817b2c4c47 Mon Sep 17 00:00:00 2001 From: Aaron Conole Date: Sat, 26 Sep 2015 18:50:42 -0400 Subject: [PATCH 1/2] af_unix: Convert the unix_sk macro to an inline function for type safety As suggested by Eric Dumazet this change replaces the #define with a static inline function to enjoy complaints by the compiler when misusing the API. Signed-off-by: Aaron Conole Signed-off-by: David S. Miller --- include/net/af_unix.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/include/net/af_unix.h b/include/net/af_unix.h index 4a167b30a12ff..cb1b9bbda3321 100644 --- a/include/net/af_unix.h +++ b/include/net/af_unix.h @@ -63,7 +63,11 @@ struct unix_sock { #define UNIX_GC_MAYBE_CYCLE 1 struct socket_wq peer_wq; }; -#define unix_sk(__sk) ((struct unix_sock *)__sk) + +static inline struct unix_sock *unix_sk(struct sock *sk) +{ + return (struct unix_sock *)sk; +} #define peer_wait peer_wq.wait From 9f389e35674f5b086edd70ed524ca0f287259725 Mon Sep 17 00:00:00 2001 From: Aaron Conole Date: Sat, 26 Sep 2015 18:50:43 -0400 Subject: [PATCH 2/2] af_unix: return data from multiple SKBs on recv() with MSG_PEEK flag 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 Signed-off-by: David S. Miller --- net/unix/af_unix.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 03ee4d359f6a4..ef31b40ad5500 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -2179,8 +2179,21 @@ static int unix_stream_read_generic(struct unix_stream_read_state *state) 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; + } + if (UNIXCB(skb).fp) + break; + + last = skb; + last_len = skb->len; + unix_state_lock(sk); + skb = skb_peek_next(skb, &sk->sk_receive_queue); + if (skb) + goto again; + unix_state_unlock(sk); break; } } while (size);