diff options
| author | Eric Dumazet <edumazet@google.com> | 2024-05-31 16:26:32 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-06-04 04:50:08 +0300 |
| commit | 2fe40483ec257de2a0d819ef88e3e76c7e261319 (patch) | |
| tree | 97a6c57c63ab893b3bf05825d7c9b3bb23927a71 | |
| parent | ffbe335b8d471f79b259e950cb20999700670456 (diff) | |
| download | linux-2fe40483ec257de2a0d819ef88e3e76c7e261319.tar.xz | |
ipv6: ioam: block BH from ioam6_output()
As explained in commit 1378817486d6 ("tipc: block BH
before using dst_cache"), net/core/dst_cache.c
helpers need to be called with BH disabled.
Disabling preemption in ioam6_output() is not good enough,
because ioam6_output() is called from process context,
lwtunnel_output() only uses rcu_read_lock().
We might be interrupted by a softirq, re-enter ioam6_output()
and corrupt dst_cache data structures.
Fix the race by using local_bh_disable() instead of
preempt_disable().
Fixes: 8cb3bf8bff3c ("ipv6: ioam: Add support for the ip6ip6 encapsulation")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Justin Iurman <justin.iurman@uliege.be>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240531132636.2637995-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/ipv6/ioam6_iptunnel.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/net/ipv6/ioam6_iptunnel.c b/net/ipv6/ioam6_iptunnel.c index 7563f8c6aa87..bf7120ecea1e 100644 --- a/net/ipv6/ioam6_iptunnel.c +++ b/net/ipv6/ioam6_iptunnel.c @@ -351,9 +351,9 @@ do_encap: goto drop; if (!ipv6_addr_equal(&orig_daddr, &ipv6_hdr(skb)->daddr)) { - preempt_disable(); + local_bh_disable(); dst = dst_cache_get(&ilwt->cache); - preempt_enable(); + local_bh_enable(); if (unlikely(!dst)) { struct ipv6hdr *hdr = ipv6_hdr(skb); @@ -373,9 +373,9 @@ do_encap: goto drop; } - preempt_disable(); + local_bh_disable(); dst_cache_set_ip6(&ilwt->cache, dst, &fl6.saddr); - preempt_enable(); + local_bh_enable(); } skb_dst_drop(skb); |