From: Daniel Borkmann Date: Mon, 25 Jul 2016 16:06:12 +0000 (+0200) Subject: udp: use sk_filter_trim_cap for udp{,6}_queue_rcv_skb X-Git-Tag: v5.15~13202^2~13 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ba66bbe5480a012108958a71cff88b23dce84956;p=platform%2Fkernel%2Flinux-starfive.git udp: use sk_filter_trim_cap for udp{,6}_queue_rcv_skb After a612769774a3 ("udp: prevent bugcheck if filter truncates packet too much"), there followed various other fixes for similar cases such as f4979fcea7fd ("rose: limit sk_filter trim to payload"). Latter introduced a new helper sk_filter_trim_cap(), where we can pass the trim limit directly to the socket filter handling. Make use of it here as well with sizeof(struct udphdr) as lower cap limit and drop the extra skb->len test in UDP's input path. Signed-off-by: Daniel Borkmann Cc: Willem de Bruijn Acked-by: Willem de Bruijn Signed-off-by: David S. Miller --- diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 4aed8fc..e61f7cd 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1581,9 +1581,7 @@ int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) udp_lib_checksum_complete(skb)) goto csum_error; - if (sk_filter(sk, skb)) - goto drop; - if (unlikely(skb->len < sizeof(struct udphdr))) + if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) goto drop; udp_csum_pull_header(skb); diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index ad5292b..81e2f98 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -618,9 +618,7 @@ int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) udp_lib_checksum_complete(skb)) goto csum_error; - if (sk_filter(sk, skb)) - goto drop; - if (unlikely(skb->len < sizeof(struct udphdr))) + if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) goto drop; udp_csum_pull_header(skb);