From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Mon, 16 Aug 2010 10:22:10 +0000 (+0000)
Subject: netfilter: {ip,ip6,arp}_tables: avoid lockdep false positive
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=001389b9581c13fe5fc357a0f89234f85af4215d;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git

netfilter: {ip,ip6,arp}_tables: avoid lockdep false positive

After commit 24b36f019 (netfilter: {ip,ip6,arp}_tables: dont block
bottom half more than necessary), lockdep can raise a warning
because we attempt to lock a spinlock with BH enabled, while
the same lock is usually locked by another cpu in a softirq context.

Disable again BH to avoid these lockdep warnings.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Diagnosed-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 6bccba31d13..51d6c316797 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -735,6 +735,7 @@ static void get_counters(const struct xt_table_info *t,
 		if (cpu == curcpu)
 			continue;
 		i = 0;
+		local_bh_disable();
 		xt_info_wrlock(cpu);
 		xt_entry_foreach(iter, t->entries[cpu], t->size) {
 			ADD_COUNTER(counters[i], iter->counters.bcnt,
@@ -742,6 +743,7 @@ static void get_counters(const struct xt_table_info *t,
 			++i;
 		}
 		xt_info_wrunlock(cpu);
+		local_bh_enable();
 	}
 	put_cpu();
 }
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index c439721b165..97b64b22c41 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -909,6 +909,7 @@ get_counters(const struct xt_table_info *t,
 		if (cpu == curcpu)
 			continue;
 		i = 0;
+		local_bh_disable();
 		xt_info_wrlock(cpu);
 		xt_entry_foreach(iter, t->entries[cpu], t->size) {
 			ADD_COUNTER(counters[i], iter->counters.bcnt,
@@ -916,6 +917,7 @@ get_counters(const struct xt_table_info *t,
 			++i; /* macro does multi eval of i */
 		}
 		xt_info_wrunlock(cpu);
+		local_bh_enable();
 	}
 	put_cpu();
 }
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 5359ef4daac..29a7bca29e3 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -922,6 +922,7 @@ get_counters(const struct xt_table_info *t,
 		if (cpu == curcpu)
 			continue;
 		i = 0;
+		local_bh_disable();
 		xt_info_wrlock(cpu);
 		xt_entry_foreach(iter, t->entries[cpu], t->size) {
 			ADD_COUNTER(counters[i], iter->counters.bcnt,
@@ -929,6 +930,7 @@ get_counters(const struct xt_table_info *t,
 			++i;
 		}
 		xt_info_wrunlock(cpu);
+		local_bh_enable();
 	}
 	put_cpu();
 }