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| author | David S. Miller <davem@sunset.davemloft.net> | 2006-04-20 09:10:50 +0200 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-04-20 09:10:50 +0200 |
| commit | dc6de33674608f978ec29f5c2f7e3af458c06f78 (patch) | |
| tree | 1b314717cdb27cf75478c13f85249f85f6997f48 | |
| parent | [TCP]: Account skb overhead in tcp_fragment (diff) | |
| download | linux-dc6de33674608f978ec29f5c2f7e3af458c06f78.tar.xz linux-dc6de33674608f978ec29f5c2f7e3af458c06f78.zip | |
[NET]: Add skb->truesize assertion checking.
Add some sanity checking. truesize should be at least sizeof(struct
sk_buff) plus the current packet length. If not, then truesize is
seriously mangled and deserves a kernel log message.
Currently we'll do the check for release of stream socket buffers.
But we can add checks to more spots over time.
Incorporating ideas from Herbert Xu.
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/skbuff.h | 7 | ||||
| -rw-r--r-- | include/net/sock.h | 1 | ||||
| -rw-r--r-- | net/core/skbuff.c | 8 | ||||
| -rw-r--r-- | net/core/stream.c | 1 |
4 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index c4619a428d9b..f8f234708b98 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -344,6 +344,13 @@ extern void skb_over_panic(struct sk_buff *skb, int len, void *here); extern void skb_under_panic(struct sk_buff *skb, int len, void *here); +extern void skb_truesize_bug(struct sk_buff *skb); + +static inline void skb_truesize_check(struct sk_buff *skb) +{ + if (unlikely((int)skb->truesize < sizeof(struct sk_buff) + skb->len)) + skb_truesize_bug(skb); +} extern int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, int getfrag(void *from, char *to, int offset, diff --git a/include/net/sock.h b/include/net/sock.h index af2b0544586e..ff8b0dad7b0f 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -454,6 +454,7 @@ static inline void sk_stream_set_owner_r(struct sk_buff *skb, struct sock *sk) static inline void sk_stream_free_skb(struct sock *sk, struct sk_buff *skb) { + skb_truesize_check(skb); sock_set_flag(sk, SOCK_QUEUE_SHRUNK); sk->sk_wmem_queued -= skb->truesize; sk->sk_forward_alloc += skb->truesize; diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 09464fa8d72f..fb3770f9c094 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -112,6 +112,14 @@ void skb_under_panic(struct sk_buff *skb, int sz, void *here) BUG(); } +void skb_truesize_bug(struct sk_buff *skb) +{ + printk(KERN_ERR "SKB BUG: Invalid truesize (%u) " + "len=%u, sizeof(sk_buff)=%Zd\n", + skb->truesize, skb->len, sizeof(struct sk_buff)); +} +EXPORT_SYMBOL(skb_truesize_bug); + /* Allocate a new skbuff. We do this ourselves so we can fill in a few * 'private' fields and also do memory statistics to find all the * [BEEP] leaks. diff --git a/net/core/stream.c b/net/core/stream.c index 35e25259fd95..e9489696f694 100644 --- a/net/core/stream.c +++ b/net/core/stream.c @@ -176,6 +176,7 @@ void sk_stream_rfree(struct sk_buff *skb) { struct sock *sk = skb->sk; + skb_truesize_check(skb); atomic_sub(skb->truesize, &sk->sk_rmem_alloc); sk->sk_forward_alloc += skb->truesize; } |