diff options
| author |   Jakub Kicinski <kuba@kernel.org> | 2025-01-29 19:15:19 -0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-02-01 16:55:44 -0800 |
| commit | 92191dd1073088753821b862b791dcc83e558e07 (patch) | |
| tree | 37810ce2f624157355409c6a471fac4c4171c729 | |
| parent | net: ipv6: fix dst refleaks in rpl, seg6 and ioam6 lwtunnels (diff) | |
| download | wireguard-linux-92191dd1073088753821b862b791dcc83e558e07.tar.xz wireguard-linux-92191dd1073088753821b862b791dcc83e558e07.zip | |
net: ipv6: fix dst ref loops in rpl, seg6 and ioam6 lwtunnels
Some lwtunnels have a dst cache for post-transformation dst.
If the packet destination did not change we may end up recording
a reference to the lwtunnel in its own cache, and the lwtunnel
state will never be freed.
Discovered by the ioam6.sh test, kmemleak was recently fixed
to catch per-cpu memory leaks. I'm not sure if rpl and seg6
can actually hit this, but in principle I don't see why not.
Fixes: 8cb3bf8bff3c ("ipv6: ioam: Add support for the ip6ip6 encapsulation")
Fixes: 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Fixes: a7a29f9c361f ("net: ipv6: add rpl sr tunnel")
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250130031519.2716843-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to '')
| -rw-r--r-- | net/ipv6/ioam6_iptunnel.c | 9 | ||||
| -rw-r--r-- | net/ipv6/rpl_iptunnel.c | 9 | ||||
| -rw-r--r-- | net/ipv6/seg6_iptunnel.c | 9 |
3 files changed, 18 insertions, 9 deletions
diff --git a/net/ipv6/ioam6_iptunnel.c b/net/ipv6/ioam6_iptunnel.c index 3936c137a572..2c383c12a431 100644 --- a/net/ipv6/ioam6_iptunnel.c +++ b/net/ipv6/ioam6_iptunnel.c @@ -410,9 +410,12 @@ do_encap: goto drop; } - local_bh_disable(); - dst_cache_set_ip6(&ilwt->cache, cache_dst, &fl6.saddr); - local_bh_enable(); + /* cache only if we don't create a dst reference loop */ + if (dst->lwtstate != cache_dst->lwtstate) { + local_bh_disable(); + dst_cache_set_ip6(&ilwt->cache, cache_dst, &fl6.saddr); + local_bh_enable(); + } err = skb_cow_head(skb, LL_RESERVED_SPACE(cache_dst->dev)); if (unlikely(err)) diff --git a/net/ipv6/rpl_iptunnel.c b/net/ipv6/rpl_iptunnel.c index 9b7d03563115..0ac4283acdf2 100644 --- a/net/ipv6/rpl_iptunnel.c +++ b/net/ipv6/rpl_iptunnel.c @@ -235,9 +235,12 @@ static int rpl_output(struct net *net, struct sock *sk, struct sk_buff *skb) goto drop; } - local_bh_disable(); - dst_cache_set_ip6(&rlwt->cache, dst, &fl6.saddr); - local_bh_enable(); + /* cache only if we don't create a dst reference loop */ + if (orig_dst->lwtstate != dst->lwtstate) { + local_bh_disable(); + dst_cache_set_ip6(&rlwt->cache, dst, &fl6.saddr); + local_bh_enable(); + } err = skb_cow_head(skb, LL_RESERVED_SPACE(dst->dev)); if (unlikely(err)) diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c index eacc4e91b48e..33833b2064c0 100644 --- a/net/ipv6/seg6_iptunnel.c +++ b/net/ipv6/seg6_iptunnel.c @@ -576,9 +576,12 @@ static int seg6_output_core(struct net *net, struct sock *sk, goto drop; } - local_bh_disable(); - dst_cache_set_ip6(&slwt->cache, dst, &fl6.saddr); - local_bh_enable(); + /* cache only if we don't create a dst reference loop */ + if (orig_dst->lwtstate != dst->lwtstate) { + local_bh_disable(); + dst_cache_set_ip6(&slwt->cache, dst, &fl6.saddr); + local_bh_enable(); + } err = skb_cow_head(skb, LL_RESERVED_SPACE(dst->dev)); if (unlikely(err)) |