| Message ID | 20220408140342.19311-1-nicolas.dichtel@6wind.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e3fa461d8b0e185b7da8a101fe94dfe6dd500ac0 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] ipv6: fix panic when forwarding a pkt with no in6 dev | expand |
On 4/8/22 07:03, Nicolas Dichtel wrote: > kongweibin reported a kernel panic in ip6_forward() when input interface > has no in6 dev associated. > > The following tc commands were used to reproduce this panic: > tc qdisc del dev vxlan100 root > tc qdisc add dev vxlan100 root netem corrupt 5% Not sure I understand how these qdisc changes can trigger a NULL idev ? Do we have another bug, like skb->cb[] content being mangled ? > > CC: stable@vger.kernel.org > Fixes: ccd27f05ae7b ("ipv6: fix 'disable_policy' for fwd packets") > Reported-by: kongweibin <kongweibin2@huawei.com> > Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> > --- > > kongweibin, could you test this patch with your setup? > > Thanks, > Nicolas > > net/ipv6/ip6_output.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c > index e23f058166af..fa63ef2bd99c 100644 > --- a/net/ipv6/ip6_output.c > +++ b/net/ipv6/ip6_output.c > @@ -485,7 +485,7 @@ int ip6_forward(struct sk_buff *skb) > goto drop; > > if (!net->ipv6.devconf_all->disable_policy && > - !idev->cnf.disable_policy && > + (!idev || !idev->cnf.disable_policy) && > !xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { > __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS); > goto drop;
On 4/8/22 8:03 AM, Nicolas Dichtel wrote: > kongweibin reported a kernel panic in ip6_forward() when input interface > has no in6 dev associated. > > The following tc commands were used to reproduce this panic: > tc qdisc del dev vxlan100 root > tc qdisc add dev vxlan100 root netem corrupt 5% > > CC: stable@vger.kernel.org > Fixes: ccd27f05ae7b ("ipv6: fix 'disable_policy' for fwd packets") > Reported-by: kongweibin <kongweibin2@huawei.com> > Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> > --- > Reviewed-by: David Ahern <dsahern@kernel.org>
> kongweibin, could you test this patch with your setup? > > Thanks, > Nicolas > > net/ipv6/ip6_output.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index > e23f058166af..fa63ef2bd99c 100644 > --- a/net/ipv6/ip6_output.c > +++ b/net/ipv6/ip6_output.c > @@ -485,7 +485,7 @@ int ip6_forward(struct sk_buff *skb) > goto drop; > > if (!net->ipv6.devconf_all->disable_policy && > - !idev->cnf.disable_policy && > + (!idev || !idev->cnf.disable_policy) && > !xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { > __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS); > goto drop; I have test the patch with my setup, it is OK. >> kongweibin reported a kernel panic in ip6_forward() when input >> interface has no in6 dev associated. >> >> The following tc commands were used to reproduce this panic: >> tc qdisc del dev vxlan100 root >> tc qdisc add dev vxlan100 root netem corrupt 5% > >Not sure I understand how these qdisc changes can trigger a NULL idev ? > >Do we have another bug, like skb->cb[] content being mangled ? > As for why qdisc makes the idev null, I tracked where the iif assigned in ip6_rcv_core, there is no problem there. Not sure what has changed that makes the iif value wrong.
Hello: This patch was applied to netdev/net.git (master) by David S. Miller <davem@davemloft.net>: On Fri, 8 Apr 2022 16:03:42 +0200 you wrote: > kongweibin reported a kernel panic in ip6_forward() when input interface > has no in6 dev associated. > > The following tc commands were used to reproduce this panic: > tc qdisc del dev vxlan100 root > tc qdisc add dev vxlan100 root netem corrupt 5% > > [...] Here is the summary with links: - [net] ipv6: fix panic when forwarding a pkt with no in6 dev https://git.kernel.org/netdev/net/c/e3fa461d8b0e You are awesome, thank you!
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index e23f058166af..fa63ef2bd99c 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -485,7 +485,7 @@ int ip6_forward(struct sk_buff *skb) goto drop; if (!net->ipv6.devconf_all->disable_policy && - !idev->cnf.disable_policy && + (!idev || !idev->cnf.disable_policy) && !xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { __IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS); goto drop;
kongweibin reported a kernel panic in ip6_forward() when input interface has no in6 dev associated. The following tc commands were used to reproduce this panic: tc qdisc del dev vxlan100 root tc qdisc add dev vxlan100 root netem corrupt 5% CC: stable@vger.kernel.org Fixes: ccd27f05ae7b ("ipv6: fix 'disable_policy' for fwd packets") Reported-by: kongweibin <kongweibin2@huawei.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> --- kongweibin, could you test this patch with your setup? Thanks, Nicolas net/ipv6/ip6_output.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)