On 6/6/17 3:06 PM, Ben Greear wrote:
> This bug has been around forever, and we recently got an intern and
> stuck him with
> trying to reproduce it on the latest kernel. It is still here. I'm not
> super excited
> about trying to fix this, but we can easily test patches if someone has a
> patch to try.
Can you try this (whitespace damaged on paste, but it is moving the lock
ahead of the fn_sernum check):
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index deea901746c8..7a44c49055c0 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -378,6 +378,7 @@ static int fib6_dump_table(struct fib6_table *table,
struct sk_buff *skb,
cb->args[5] = w->root->fn_sernum;
}
} else {
+ read_lock_bh(&table->tb6_lock);
if (cb->args[5] != w->root->fn_sernum) {
/* Begin at the root if the tree changed */
cb->args[5] = w->root->fn_sernum;
@@ -387,7 +388,6 @@ static int fib6_dump_table(struct fib6_table *table,
struct sk_buff *skb,
} else
w->skip = 0;
- read_lock_bh(&table->tb6_lock);
res = fib6_walk_continue(w);
read_unlock_bh(&table->tb6_lock);
if (res <= 0) {
