Re: [PATCH v2] ipv6: Fix protocol resubmission
From: Sergei Shtylyov <hidden>
Date: 2015-05-29 20:28:04
Hello. On 05/29/2015 11:04 PM, Josh Hunt wrote:
I came across this problem while trying to use UDP encapsulation with IPv6. The change below fixes that, but it was not immediately apparent if there are any other protocols relying on this broken behavior. FWIW the behavior below now matches IPv4.
Josh
Need "Signed-off-by:" line insted of this.
v2: Actually sets nexthdr so we can use it ;)
Normally goes after ---, not before.
---
UDP encapsulation is broken on IPv6 because it expects when it returns a negative value that the packet will be resubmitted to the stack with the handler corresponding to the return value. The check currently looks for return values > 0 and then resubmits.
This patch fixes that check and also moves the resubmit label to take advantage of the return code identifying the next protocol we want to process.
Signed-off-by: Josh Hunt <redacted> --- net/ipv6/ip6_input.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
quoted hunk ↗ jump to hunk
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c index f2e464e..e16c289 100644 --- a/net/ipv6/ip6_input.c +++ b/net/ipv6/ip6_input.c
[...]
quoted hunk ↗ jump to hunk
@@ -246,9 +246,10 @@ resubmit: goto discard; ret = ipprot->handler(skb); - if (ret > 0) + if (ret < 0) { + nexthdr = -ret; goto resubmit; - else if (ret == 0) + } else if (ret == 0) IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDELIVERS);
The CodingStyle dictates that all branches must have {} if at least one
has them.
[...]
WBR, Sergei