From 9772b54c55266ce80c639a80aa68eeb908f8ecf5 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Wed, 3 Dec 2014 12:13:58 +0100 Subject: net: sctp: use MAX_HEADER for headroom reserve in output path MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit To accomodate for enough headroom for tunnels, use MAX_HEADER instead of LL_MAX_HEADER. Robert reported that he has hit after roughly 40hrs of trinity an skb_under_panic() via SCTP output path (see reference). I couldn't reproduce it from here, but not using MAX_HEADER as elsewhere in other protocols might be one possible cause for this. In any case, it looks like accounting on chunks themself seems to look good as the skb already passed the SCTP output path and did not hit any skb_over_panic(). Given tunneling was enabled in his .config, the headroom would have been expanded by MAX_HEADER in this case. Reported-by: Robert Święcki Reference: https://lkml.org/lkml/2014/12/1/507 Fixes: 594ccc14dfe4d ("[SCTP] Replace incorrect use of dev_alloc_skb with alloc_skb in sctp_packet_transmit().") Signed-off-by: Daniel Borkmann Acked-by: Vlad Yasevich Acked-by: Neil Horman Signed-off-by: David S. Miller --- net/sctp/output.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/sctp/output.c b/net/sctp/output.c index 42dffd428389..fc5e45b8a832 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -401,12 +401,12 @@ int sctp_packet_transmit(struct sctp_packet *packet) sk = chunk->skb->sk; /* Allocate the new skb. */ - nskb = alloc_skb(packet->size + LL_MAX_HEADER, GFP_ATOMIC); + nskb = alloc_skb(packet->size + MAX_HEADER, GFP_ATOMIC); if (!nskb) goto nomem; /* Make sure the outbound skb has enough header room reserved. */ - skb_reserve(nskb, packet->overhead + LL_MAX_HEADER); + skb_reserve(nskb, packet->overhead + MAX_HEADER); /* Set the owning socket so that we know where to get the * destination IP address. -- cgit v1.2.3-58-ga151