[NETFILTER]: Use pskb_trim in {ip,ip6,nfnetlink}_queue
Based on patch by James D. Nurmi:
I've got some code very dependant on nfnetlink_queue, and turned up a
large number of warns coming from skb_trim. While it's quite possibly
my code, having not seen it on older kernels made me a bit suspect.
Anyhow, based on some googling I turned up this thread:
http://lkml.org/lkml/2006/8/13/56
And believe the issue to be related, so attached is a small patch to
the kernel -- not sure if this is completely correct, but for anyone
else hitting the WARN_ON(1) in skbuff.h, it might be helpful..
Signed-off-by: James D. Nurmi <jdnurmi@gmail.com>
Ported to ip6_queue and nfnetlink_queue and added return value
checks.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c
index 7edad79..97556cc 100644
--- a/net/ipv4/netfilter/ip_queue.c
+++ b/net/ipv4/netfilter/ip_queue.c
@@ -351,9 +351,10 @@
if (v->data_len < sizeof(*user_iph))
return 0;
diff = v->data_len - e->skb->len;
- if (diff < 0)
- skb_trim(e->skb, v->data_len);
- else if (diff > 0) {
+ if (diff < 0) {
+ if (pskb_trim(e->skb, v->data_len))
+ return -ENOMEM;
+ } else if (diff > 0) {
if (v->data_len > 0xFFFF)
return -EINVAL;
if (diff > skb_tailroom(e->skb)) {
diff --git a/net/ipv6/netfilter/ip6_queue.c b/net/ipv6/netfilter/ip6_queue.c
index 9510c24..9fec832 100644
--- a/net/ipv6/netfilter/ip6_queue.c
+++ b/net/ipv6/netfilter/ip6_queue.c
@@ -349,9 +349,10 @@
if (v->data_len < sizeof(*user_iph))
return 0;
diff = v->data_len - e->skb->len;
- if (diff < 0)
- skb_trim(e->skb, v->data_len);
- else if (diff > 0) {
+ if (diff < 0) {
+ if (pskb_trim(e->skb, v->data_len))
+ return -ENOMEM;
+ } else if (diff > 0) {
if (v->data_len > 0xFFFF)
return -EINVAL;
if (diff > skb_tailroom(e->skb)) {
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 6e4ada3..e815a9a 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -622,9 +622,10 @@
int diff;
diff = data_len - e->skb->len;
- if (diff < 0)
- skb_trim(e->skb, data_len);
- else if (diff > 0) {
+ if (diff < 0) {
+ if (pskb_trim(e->skb, data_len))
+ return -ENOMEM;
+ } else if (diff > 0) {
if (data_len > 0xFFFF)
return -EINVAL;
if (diff > skb_tailroom(e->skb)) {