From 0eca93bcf73e5939053a94f7c48f8d6fe6199e00 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Tue, 14 Apr 2009 02:09:43 -0700 Subject: [PATCH] tun: Fix crash with non-GSO users When I made the tun driver use non-linear packets as the preferred option, it broke non-GSO users because they would end up allocating a completely non-linear packet, which triggers a crash when we call eth_type_trans. This patch reverts non-GSO users to using linear packets and adds a check to ensure that GSO users can't cause crashes in the same way. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- drivers/net/tun.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index a1b0697..16716ae 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -518,7 +518,7 @@ static inline struct sk_buff *tun_alloc_skb(struct tun_struct *tun, int err; /* Under a page? Don't bother with paged skb. */ - if (prepad + len < PAGE_SIZE) + if (prepad + len < PAGE_SIZE || !linear) linear = len; skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, @@ -565,7 +565,8 @@ static __inline__ ssize_t tun_get_user(struct tun_struct *tun, if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) { align = NET_IP_ALIGN; - if (unlikely(len < ETH_HLEN)) + if (unlikely(len < ETH_HLEN || + (gso.hdr_len && gso.hdr_len < ETH_HLEN))) return -EINVAL; } -- 2.7.4