]> www.infradead.org Git - users/jedix/linux-maple.git/commit
ipv6: sr: block BH in seg6_output_core() and seg6_input_core()
authorEric Dumazet <edumazet@google.com>
Fri, 31 May 2024 13:26:34 +0000 (13:26 +0000)
committerJakub Kicinski <kuba@kernel.org>
Tue, 4 Jun 2024 01:50:08 +0000 (18:50 -0700)
commitc0b98ac1cc104f48763cdb27b1e9ac25fd81fc90
tree47bf3586373335218130b8daac1fc50b85a38955
parentdb0090c6eb12c31246438b7fe2a8f1b833e7a653
ipv6: sr: block BH in seg6_output_core() and seg6_input_core()

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 seg6_output_core() is not good enough,
because seg6_output_core() is called from process context,
lwtunnel_output() only uses rcu_read_lock().

We might be interrupted by a softirq, re-enter seg6_output_core()
and corrupt dst_cache data structures.

Fix the race by using local_bh_disable() instead of
preempt_disable().

Apply a similar change in seg6_input_core().

Fixes: fa79581ea66c ("ipv6: sr: fix several BUGs when preemption is enabled")
Fixes: 6c8702c60b88 ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Lebrun <dlebrun@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240531132636.2637995-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net/ipv6/seg6_iptunnel.c