lkml.org 
[lkml]   [2015]   [Aug]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[PATCH 3.2 093/110] inet: frags: fix defragmented packet's IP header for af_packet
3.2.71-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Edward Hyunkoo Jee <edjee@google.com>

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>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
net/ipv4/ip_fragment.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -385,7 +385,7 @@ static int ip_frag_queue(struct ipq *qp,
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? */
@@ -415,7 +415,7 @@ static int ip_frag_queue(struct ipq *qp,
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);
@@ -638,6 +638,8 @@ static int ip_frag_reasm(struct ipq *qp,
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;


\
 
 \ /
  Last update: 2015-08-10 13:01    [W:0.376 / U:0.808 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site