summaryrefslogtreecommitdiffstats
path: root/net
diff options
context:
space:
mode:
authorChangli Gao <xiaosuo@gmail.com>2010-06-02 04:55:02 +0000
committerDavid S. Miller <davem@davemloft.net>2010-06-03 03:28:27 -0700
commitdb2c24175d149b55784f7cb2c303622ce962c1ae (patch)
tree37c34d4289975bcea43d50bf6eff405f74310db5 /net
parent3df95ce948dc8ceef07b49003ab944aa047f2a79 (diff)
downloadlinux-db2c24175d149b55784f7cb2c303622ce962c1ae.tar.bz2
act_pedit: access skb->data safely
access skb->data safely we should use skb_header_pointer() and skb_store_bits() to access skb->data to handle small or non-linear skbs. Signed-off-by: Changli Gao <xiaosuo@gmail.com> ---- net/sched/act_pedit.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r--net/sched/act_pedit.c24
1 files changed, 14 insertions, 10 deletions
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
index fdbd0b7bd840..50e3d945e1f4 100644
--- a/net/sched/act_pedit.c
+++ b/net/sched/act_pedit.c
@@ -125,7 +125,7 @@ static int tcf_pedit(struct sk_buff *skb, struct tc_action *a,
{
struct tcf_pedit *p = a->priv;
int i, munged = 0;
- u8 *pptr;
+ unsigned int off;
if (!(skb->tc_verd & TC_OK2MUNGE)) {
/* should we set skb->cloned? */
@@ -134,7 +134,7 @@ static int tcf_pedit(struct sk_buff *skb, struct tc_action *a,
}
}
- pptr = skb_network_header(skb);
+ off = skb_network_offset(skb);
spin_lock(&p->tcf_lock);
@@ -144,17 +144,17 @@ static int tcf_pedit(struct sk_buff *skb, struct tc_action *a,
struct tc_pedit_key *tkey = p->tcfp_keys;
for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
- u32 *ptr;
+ u32 *ptr, _data;
int offset = tkey->off;
if (tkey->offmask) {
- if (skb->len > tkey->at) {
- char *j = pptr + tkey->at;
- offset += ((*j & tkey->offmask) >>
- tkey->shift);
- } else {
+ char *d, _d;
+
+ d = skb_header_pointer(skb, off + tkey->at, 1,
+ &_d);
+ if (!d)
goto bad;
- }
+ offset += (*d & tkey->offmask) >> tkey->shift;
}
if (offset % 4) {
@@ -169,9 +169,13 @@ static int tcf_pedit(struct sk_buff *skb, struct tc_action *a,
goto bad;
}
- ptr = (u32 *)(pptr+offset);
+ ptr = skb_header_pointer(skb, off + offset, 4, &_data);
+ if (!ptr)
+ goto bad;
/* just do it, baby */
*ptr = ((*ptr & tkey->mask) ^ tkey->val);
+ if (ptr == &_data)
+ skb_store_bits(skb, off + offset, ptr, 4);
munged++;
}