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| author | Tejaswi Tanikella <tejaswit@codeaurora.org> | 2017-10-23 11:46:03 +0530 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-11-01 12:15:29 +0100 |
| commit | 7400bb4b5800831581a82f71700af6a5e815c3c8 (patch) | |
| tree | aabbc224b7f7d620573fd638431a26f0442eac59 /net | |
| parent | 0414c78f14861cb704d6e6888efd53dd36e3bdde (diff) | |
| download | linux-7400bb4b5800831581a82f71700af6a5e815c3c8.tar.gz linux-7400bb4b5800831581a82f71700af6a5e815c3c8.tar.bz2 linux-7400bb4b5800831581a82f71700af6a5e815c3c8.zip | |
netfilter: nf_reject_ipv4: Fix use-after-free in send_reset
niph is not updated after pskb_expand_head changes the skb head. It
still points to the freed data, which is then used to update tot_len and
checksum. This could cause use-after-free poison crash.
Update niph, if ip_route_me_harder does not fail.
This only affects the interaction with REJECT targets and br_netfilter.
Signed-off-by: Tejaswi Tanikella <tejaswit@codeaurora.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/netfilter/nf_reject_ipv4.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/nf_reject_ipv4.c b/net/ipv4/netfilter/nf_reject_ipv4.c index eeacbdaf7cdf..5cd06ba3535d 100644 --- a/net/ipv4/netfilter/nf_reject_ipv4.c +++ b/net/ipv4/netfilter/nf_reject_ipv4.c @@ -132,6 +132,8 @@ void nf_send_reset(struct net *net, struct sk_buff *oldskb, int hook) if (ip_route_me_harder(net, nskb, RTN_UNSPEC)) goto free_nskb; + niph = ip_hdr(nskb); + /* "Never happens" */ if (nskb->len > dst_mtu(skb_dst(nskb))) goto free_nskb; |