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author | Eric Dumazet <edumazet@google.com> | 2024-05-31 16:26:32 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-06-21 15:38:15 +0300 |
commit | db21c1ee6b6dc033032e82524a3b68e7bcf9bbb3 (patch) | |
tree | 205551184c8b9362ea0c2c0a7798d970e2b1e1a0 | |
parent | 9ee14af24e67ef170108db547f7d1f701b3f2bc5 (diff) | |
download | linux-db21c1ee6b6dc033032e82524a3b68e7bcf9bbb3.tar.xz |
ipv6: ioam: block BH from ioam6_output()
[ Upstream commit 2fe40483ec257de2a0d819ef88e3e76c7e261319 ]
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>
Signed-off-by: Sasha Levin <sashal@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 f6f5b83dd954..a5cfc5b0b206 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); |