net: fix percpu memory leaks
This patch fixes following problems :
1) percpu_counter_init() can return an error, therefore
init_frag_mem_limit() must propagate this error so that
inet_frags_init_net() can do the same up to its callers.
2) If ip[46]_frags_ns_ctl_register() fail, we must unwind
properly and free the percpu_counter.
Without this fix, we leave freed object in percpu_counters
global list (if CONFIG_HOTPLUG_CPU) leading to crashes.
This bug was detected by KASAN and syzkaller tool
(http://github.com/google/syzkaller)
Fixes: 6d7b857d541e ("net: use lib/percpu_counter API for fragmentation mem accounting")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/inet_frag.h b/include/net/inet_frag.h
index 53eead2..ac42bbb 100644
--- a/include/net/inet_frag.h
+++ b/include/net/inet_frag.h
@@ -108,7 +108,15 @@
int inet_frags_init(struct inet_frags *);
void inet_frags_fini(struct inet_frags *);
-void inet_frags_init_net(struct netns_frags *nf);
+static inline int inet_frags_init_net(struct netns_frags *nf)
+{
+ return percpu_counter_init(&nf->mem, 0, GFP_KERNEL);
+}
+static inline void inet_frags_uninit_net(struct netns_frags *nf)
+{
+ percpu_counter_destroy(&nf->mem);
+}
+
void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f);
void inet_frag_kill(struct inet_frag_queue *q, struct inet_frags *f);
@@ -154,11 +162,6 @@
__percpu_counter_add(&nf->mem, i, frag_percpu_counter_batch);
}
-static inline void init_frag_mem_limit(struct netns_frags *nf)
-{
- percpu_counter_init(&nf->mem, 0, GFP_KERNEL);
-}
-
static inline unsigned int sum_frag_mem_limit(struct netns_frags *nf)
{
unsigned int res;