diff options
| author | Hoang Le <hoang.h.le@dektek.com.au> | 2018-02-08 19:16:25 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-02-08 23:30:40 +0300 |
| commit | 55b3280d1e471795c08dbbe17325720a843e104c (patch) | |
| tree | 540f61caa564a39a197d6980c0a244f1cd93a807 | |
| parent | eb53f7af6f15285e2f6ada97285395343ce9f433 (diff) | |
| download | linux-55b3280d1e471795c08dbbe17325720a843e104c.tar.xz | |
tipc: fix skb truesize/datasize ratio control
In commit d618d09a68e4 ("tipc: enforce valid ratio between skb truesize
and contents") we introduced a test for ensuring that the condition
truesize/datasize <= 4 is true for a received buffer. Unfortunately this
test has two problems.
- Because of the integer arithmetics the test
if (skb->truesize / buf_roundup_len(skb) > 4) will miss all
ratios [4 < ratio < 5], which was not the intention.
- The buffer returned by skb_copy() inherits skb->truesize of the
original buffer, which doesn't help the situation at all.
In this commit, we change the ratio condition and replace skb_copy()
with a call to skb_copy_expand() to finally get this right.
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/tipc/msg.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/tipc/msg.c b/net/tipc/msg.c index 55d8ba92291d..4e1c6f6450bb 100644 --- a/net/tipc/msg.c +++ b/net/tipc/msg.c @@ -208,8 +208,8 @@ bool tipc_msg_validate(struct sk_buff **_skb) int msz, hsz; /* Ensure that flow control ratio condition is satisfied */ - if (unlikely(skb->truesize / buf_roundup_len(skb) > 4)) { - skb = skb_copy(skb, GFP_ATOMIC); + if (unlikely(skb->truesize / buf_roundup_len(skb) >= 4)) { + skb = skb_copy_expand(skb, BUF_HEADROOM, 0, GFP_ATOMIC); if (!skb) return false; kfree_skb(*_skb); |