4.15-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
commit de526f401284e1638d4c97cb5a4c292ac3f37655 upstream.
syszkaller found that rcu was not held in hashlimit_mt_common()
We only need to enable BH at this point.
Fixes: bea74641e378 ("netfilter: xt_hashlimit: add rate match mode") Signed-off-by: Eric Dumazet edumazet@google.com Reported-by: syzkaller syzkaller@googlegroups.com Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/netfilter/xt_hashlimit.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/netfilter/xt_hashlimit.c +++ b/net/netfilter/xt_hashlimit.c @@ -774,7 +774,7 @@ hashlimit_mt_common(const struct sk_buff if (!dh->rateinfo.prev_window && (dh->rateinfo.current_rate <= dh->rateinfo.burst)) { spin_unlock(&dh->lock); - rcu_read_unlock_bh(); + local_bh_enable(); return !(cfg->mode & XT_HASHLIMIT_INVERT); } else { goto overlimit;