summaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorWillem de Bruijn <willemb@google.com>2018-05-17 13:13:29 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-05-26 08:48:57 +0200
commit671cf50f4c2f55652495d98fa4306aa8641b2860 (patch)
tree6057a3c8ca44635e202fb80fc32a9c8d453ca4e4 /net
parente2da30c54e49d7c989484865b838aeccad708d00 (diff)
net: test tailroom before appending to linear skb
[ Upstream commit 113f99c3358564a0647d444c2ae34e8b1abfd5b9 ] Device features may change during transmission. In particular with corking, a device may toggle scatter-gather in between allocating and writing to an skb. Do not unconditionally assume that !NETIF_F_SG at write time implies that the same held at alloc time and thus the skb has sufficient tailroom. This issue predates git history. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
-rw-r--r--net/ipv4/ip_output.c3
-rw-r--r--net/ipv6/ip6_output.c3
2 files changed, 4 insertions, 2 deletions
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 09c73dd541c5..10286432f684 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -1062,7 +1062,8 @@ alloc_new_skb:
if (copy > length)
copy = length;
- if (!(rt->dst.dev->features&NETIF_F_SG)) {
+ if (!(rt->dst.dev->features&NETIF_F_SG) &&
+ skb_tailroom(skb) >= copy) {
unsigned int off;
off = skb->len;
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index bfa710e8b615..74786783834b 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1529,7 +1529,8 @@ alloc_new_skb:
if (copy > length)
copy = length;
- if (!(rt->dst.dev->features&NETIF_F_SG)) {
+ if (!(rt->dst.dev->features&NETIF_F_SG) &&
+ skb_tailroom(skb) >= copy) {
unsigned int off;
off = skb->len;