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| author | Hangbin Liu <liuhangbin@gmail.com> | 2019-02-07 18:36:11 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-02-07 10:48:42 -0800 |
| commit | 173656accaf583698bac3f9e269884ba60d51ef4 (patch) | |
| tree | 79016b006cd80fb1139261887c3f80eda1849f9c /net/ipv6/sit.c | |
| parent | c0a47e44c0980b3b23ee31fa7936d70ea5dce491 (diff) | |
| download | lwn-173656accaf583698bac3f9e269884ba60d51ef4.tar.gz lwn-173656accaf583698bac3f9e269884ba60d51ef4.zip | |
sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()
If we disabled IPv6 from the kernel command line (ipv6.disable=1), we should
not call ip6_err_gen_icmpv6_unreach(). This:
ip link add sit1 type sit local 192.0.2.1 remote 192.0.2.2 ttl 1
ip link set sit1 up
ip addr add 198.51.100.1/24 dev sit1
ping 198.51.100.2
if IPv6 is disabled at boot time, will crash the kernel.
v2: there's no need to use in6_dev_get(), use __in6_dev_get() instead,
as we only need to check that idev exists and we are under
rcu_read_lock() (from netif_receive_skb_internal()).
Reported-by: Jianlin Shi <jishi@redhat.com>
Fixes: ca15a078bd90 ("sit: generate icmpv6 error when receiving icmpv4 error")
Cc: Oussama Ghorbel <ghorbel@pivasoftware.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/sit.c')
| -rw-r--r-- | net/ipv6/sit.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 1e03305c0549..e8a1dabef803 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -546,7 +546,8 @@ static int ipip6_err(struct sk_buff *skb, u32 info) } err = 0; - if (!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4, type, data_len)) + if (__in6_dev_get(skb->dev) && + !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4, type, data_len)) goto out; if (t->parms.iph.daddr == 0) |