| From | lizf@kernel ... | Subject | [PATCH 3.4 033/107] inet: frags: fix defragmented packet's IP header for af_packet | Date | Wed, 16 Mar 2016 16:05:27 +0800 |
| |
From: Edward Hyunkoo Jee <edjee@google.com>
3.4.111-rc1 review patch. If anyone has any objections, please let me know.
------------------
commit 0848f6428ba3a2e42db124d41ac6f548655735bf upstream.
When ip_frag_queue() computes positions, it assumes that the passed sk_buff does not contain L2 headers.
However, when PACKET_FANOUT_FLAG_DEFRAG is used, IP reassembly functions can be called on outgoing packets that contain L2 headers.
Also, IPv4 checksum is not corrected after reassembly.
Fixes: 7736d33f4262 ("packet: Add pre-defragmentation support for ipv4 fanouts.") Signed-off-by: Edward Hyunkoo Jee <edjee@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Jerry Chu <hkchu@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [lizf: Backported to 3.4: adjust context] Signed-off-by: Zefan Li <lizefan@huawei.com> --- net/ipv4/ip_fragment.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index 4a40457..f459793 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -384,7 +384,7 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) ihl = ip_hdrlen(skb); /* Determine the position of this fragment. */ - end = offset + skb->len - ihl; + end = offset + skb->len - skb_network_offset(skb) - ihl; err = -EINVAL; /* Is this the final fragment? */ @@ -414,7 +414,7 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) goto err; err = -ENOMEM; - if (pskb_pull(skb, ihl) == NULL) + if (!pskb_pull(skb, skb_network_offset(skb) + ihl)) goto err; err = pskb_trim_rcsum(skb, end - offset); @@ -637,6 +637,8 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev, iph->frag_off = 0; iph->tot_len = htons(len); iph->tos |= ecn; + ip_send_check(iph); + IP_INC_STATS_BH(net, IPSTATS_MIB_REASMOKS); qp->q.fragments = NULL; qp->q.fragments_tail = NULL; -- 1.9.1
|