From: Bjørn Mork Date: Thu, 6 May 2010 03:44:34 +0000 (+0000) Subject: ipv4: udp: fix short packet and bad checksum logging X-Git-Tag: firefly_0821_release~10186^2~1620 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=5f4213d39b4965791875f6e10f6f7268ba8dfc2c;p=firefly-linux-kernel-4.4.55.git ipv4: udp: fix short packet and bad checksum logging commit ccc2d97cb7c798e785c9f198de243e2b59f7073b upstream. commit 2783ef23 moved the initialisation of saddr and daddr after pskb_may_pull() to avoid a potential data corruption. Unfortunately also placing it after the short packet and bad checksum error paths, where these variables are used for logging. The result is bogus output like [92238.389505] UDP: short packet: From 2.0.0.0:65535 23715/178 to 0.0.0.0:65535 Moving the saddr and daddr initialisation above the error paths, while still keeping it after the pskb_may_pull() to keep the fix from commit 2783ef23. Signed-off-by: Bjørn Mork Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 0fa9f70e4b19..c322f4429fc9 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1292,6 +1292,9 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, uh = udp_hdr(skb); ulen = ntohs(uh->len); + saddr = ip_hdr(skb)->saddr; + daddr = ip_hdr(skb)->daddr; + if (ulen > skb->len) goto short_packet; @@ -1305,9 +1308,6 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, if (udp4_csum_init(skb, uh, proto)) goto csum_error; - saddr = ip_hdr(skb)->saddr; - daddr = ip_hdr(skb)->daddr; - if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST)) return __udp4_lib_mcast_deliver(net, skb, uh, saddr, daddr, udptable);