From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754082AbZCNATy (ORCPT ); Fri, 13 Mar 2009 20:19:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752486AbZCNASZ (ORCPT ); Fri, 13 Mar 2009 20:18:25 -0400 Received: from kroah.org ([198.145.64.141]:46611 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750926AbZCNASY (ORCPT ); Fri, 13 Mar 2009 20:18:24 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Fri Mar 13 17:07:39 2009 Message-Id: <20090314000739.203280155@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Fri, 13 Mar 2009 17:05:12 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, "David S. Miller" Subject: [patch 04/96] net: Kill skb_truesize_check(), it only catches false-positives. References: <20090314000508.803142980@mini.kroah.org> Content-Disposition: inline; filename=net-kill-skb_truesize_check-it-only-catches-false-positives.patch In-Reply-To: <20090314001449.GA4485@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: David S. Miller [ Upstream commit 92a0acce186cde8ead56c6915d9479773673ea1a ] A long time ago we had bugs, primarily in TCP, where we would modify skb->truesize (for TSO queue collapsing) in ways which would corrupt the socket memory accounting. skb_truesize_check() was added in order to try and catch this error more systematically. However this debugging check has morphed into a Frankenstein of sorts and these days it does nothing other than catch false-positives. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/linux/skbuff.h | 9 --------- include/net/sock.h | 1 - net/core/skbuff.c | 8 -------- net/core/sock.c | 1 - 4 files changed, 19 deletions(-) --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -395,15 +395,6 @@ extern void skb_over_panic(struct 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) -{ - int len = sizeof(struct sk_buff) + skb->len; - - if (unlikely((int)skb->truesize < 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, --- a/include/net/sock.h +++ b/include/net/sock.h @@ -777,7 +777,6 @@ static inline void sk_mem_uncharge(struc static inline void sk_wmem_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_mem_uncharge(sk, skb->truesize); --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -143,14 +143,6 @@ void skb_under_panic(struct sk_buff *skb 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. --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1136,7 +1136,6 @@ void sock_rfree(struct sk_buff *skb) { struct sock *sk = skb->sk; - skb_truesize_check(skb); atomic_sub(skb->truesize, &sk->sk_rmem_alloc); sk_mem_uncharge(skb->sk, skb->truesize); }