tun: fix a memory leak for tfile->tx_array
tfile->tun could be detached before we close the tun fd,
via tun_detach_all(), so it should not be used to check for
tfile->tx_array.
As Jason suggested, we probably have to clean it up
unconditionally both in __tun_deatch() and tun_detach_all(),
but this requires to check if it is initialized or not.
Currently skb_array_cleanup() doesn't have such a check,
so I check it in the caller and introduce a helper function,
it is a bit ugly but we can always improve it in net-next.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Fixes: 1576d9860599 ("tun: switch to use skb array for tx")
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 4f4a842..a8ec589 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -611,6 +611,14 @@
skb_queue_purge(&tfile->sk.sk_error_queue);
}
+static void tun_cleanup_tx_array(struct tun_file *tfile)
+{
+ if (tfile->tx_array.ring.queue) {
+ skb_array_cleanup(&tfile->tx_array);
+ memset(&tfile->tx_array, 0, sizeof(tfile->tx_array));
+ }
+}
+
static void __tun_detach(struct tun_file *tfile, bool clean)
{
struct tun_file *ntfile;
@@ -657,8 +665,7 @@
tun->dev->reg_state == NETREG_REGISTERED)
unregister_netdevice(tun->dev);
}
- if (tun)
- skb_array_cleanup(&tfile->tx_array);
+ tun_cleanup_tx_array(tfile);
sock_put(&tfile->sk);
}
}
@@ -700,11 +707,13 @@
/* Drop read queue */
tun_queue_purge(tfile);
sock_put(&tfile->sk);
+ tun_cleanup_tx_array(tfile);
}
list_for_each_entry_safe(tfile, tmp, &tun->disabled, next) {
tun_enable_queue(tfile);
tun_queue_purge(tfile);
sock_put(&tfile->sk);
+ tun_cleanup_tx_array(tfile);
}
BUG_ON(tun->numdisabled != 0);
@@ -2851,6 +2860,8 @@
sock_set_flag(&tfile->sk, SOCK_ZEROCOPY);
+ memset(&tfile->tx_array, 0, sizeof(tfile->tx_array));
+
return 0;
}