From 88fae87327a2261cf8db078f6ce4e5a3e55b30b1 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Fri, 26 Jan 2018 01:36:31 +0200 Subject: [PATCH] tap: fix use-after-free Lockless access to __ptr_ring_full is only legal if ring is never resized, otherwise it might cause use-after free errors. Simply drop the lockless test, we'll drop the packet a bit later when produce fails. Fixes: 362899b8 ("macvtap: switch to use skb array") Signed-off-by: Michael S. Tsirkin Signed-off-by: David S. Miller --- drivers/net/tap.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/net/tap.c b/drivers/net/tap.c index 7c38659b2a76..77872699c45d 100644 --- a/drivers/net/tap.c +++ b/drivers/net/tap.c @@ -330,9 +330,6 @@ rx_handler_result_t tap_handle_frame(struct sk_buff **pskb) if (!q) return RX_HANDLER_PASS; - if (__ptr_ring_full(&q->ring)) - goto drop; - skb_push(skb, ETH_HLEN); /* Apply the forward feature mask so that we perform segmentation -- 2.30.2