Re: [PATCH net v2 2/4] ipv4: add defensive check for CHECKSUM_PARTIAL skbs in ip_fragment
From: Sergei Shtylyov <hidden>
Date: 2015-10-27 19:01:48
Hello. On 10/27/2015 06:02 PM, Hannes Frederic Sowa wrote:
quoted hunk ↗ jump to hunk
CHECKSUM_PARTIAL skbs should never arrive in ip_fragment. If we get one of those warn about them once and handle them gracefully by recalculating the checksum. Cc: Eric Dumazet <edumazet@google.com> Cc: Vlad Yasevich <redacted> Cc: Benjamin Coddington <redacted> Cc: Tom Herbert <redacted> Signed-off-by: Hannes Frederic Sowa <redacted> --- net/ipv4/ip_output.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 0b02417..3f94a3b 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c@@ -533,6 +533,11 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, dev = rt->dst.dev; + /* for offloaded checksums cleanup checksum before fragmentation */ + if (WARN_ON_ONCE(skb->ip_summed == CHECKSUM_PARTIAL) && + (err = skb_checksum_help(skb)))
scripts/checkpatch.pl shou;d have complained about using = in the *if*
expression.
+ goto fail; + /* * Point into the IP datagram header. */
[...] MBR, Sergei