Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-10 22:21:40 +00:00
Code Issues Packages Projects Releases Wiki Activity

net: Fix range checks in tcf_valid_offset().

Browse Source 
This function has three bugs:

1) The offset should be valid most of the time, this is just
   a sanity check, therefore we should use "likely" not "unlikely"

2) This is the only place where we can check for arithmetic overflow
   of the pointer plus the length.

3) The existing range checks are off by one, the valid range is
   skb->head to skb_tail_pointer(), inclusive.

Based almost entirely upon a patch by Ralph Loader.

Reported-by: Ralph Loader <suckfish@ihug.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2010-12-21 12:43:16 -08:00
parent aa3e219997
commit da521b2c4f
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
include/net/pkt_cls.h
View File

@ -323,7 +323,9 @@ static inline unsigned char * tcf_get_base_ptr(struct sk_buff *skb, int layer)
static inline int tcf_valid_offset(const struct sk_buff *skb, static inline int tcf_valid_offset(const struct sk_buff *skb,
const unsigned char *ptr, const int len) const unsigned char *ptr, const int len)
{ {
return unlikely((ptr + len) < skb_tail_pointer(skb) && ptr > skb->head); return likely((ptr + len) <= skb_tail_pointer(skb) &&
ptr >= skb->head &&
(ptr <= (ptr + len)));
} }
#ifdef CONFIG_NET_CLS_IND #ifdef CONFIG_NET_CLS_IND