diff options
| author | stephen hemminger <shemminger@vyatta.com> | 2010-08-02 13:44:13 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-08-02 22:07:45 -0700 |
| commit | 66d50d25502cd9b7d6e3ebbf4e241259c1283eaf (patch) | |
| tree | a8738a77a087122167a2d881a8d0833255bbadb4 /net | |
| parent | eabd8ba9060444cac5b89a3306e607c15ec37418 (diff) | |
| download | lwn-66d50d25502cd9b7d6e3ebbf4e241259c1283eaf.tar.gz lwn-66d50d25502cd9b7d6e3ebbf4e241259c1283eaf.zip | |
u32: negative offset fix
It was possible to use a negative offset in a u32 match to reference
the ethernet header or other parts of the link layer header.
This fixes the regression caused by:
commit fbc2e7d9cf49e0bf89b9e91fd60a06851a855c5d
Author: Changli Gao <xiaosuo@gmail.com>
Date: Wed Jun 2 07:32:42 2010 -0700
cls_u32: use skb_header_pointer() to dereference data safely
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/sched/cls_u32.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c index 4f522143811e..7416a5c73b2a 100644 --- a/net/sched/cls_u32.c +++ b/net/sched/cls_u32.c @@ -134,10 +134,12 @@ next_knode: #endif for (i = n->sel.nkeys; i>0; i--, key++) { - unsigned int toff; + int toff = off + key->off + (off2 & key->offmask); __be32 *data, _data; - toff = off + key->off + (off2 & key->offmask); + if (skb_headroom(skb) + toff < 0) + goto out; + data = skb_header_pointer(skb, toff, 4, &_data); if (!data) goto out; |