From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chen Gang Subject: [Regression net-next] include/linux/skbuff.h: "1a37e41 net: Use 16bits for *_headers fields of struct skbuff" Date: Thu, 30 May 2013 19:21:17 +0800 Message-ID: <51A7362D.4070501@asianux.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: David Miller , netdev To: horms@verge.net.au Return-path: Received: from intranet.asianux.com ([58.214.24.6]:12839 "EHLO intranet.asianux.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S968151Ab3E3LWJ (ORCPT ); Thu, 30 May 2013 07:22:09 -0400 Sender: netdev-owner@vger.kernel.org List-ID: Hello Maintainers: When not define NET_SKBUFF_DATA_USES_OFFSET, 'sk_buff_data_t' will be a pointer, then the last parameter of memmove() in mangle_contents() will be a pointer in "net/netfilter/nf_nat_helper.c". The reason is from the patch "1a37e41 net: Use 16bits for *_headers fields of struct skbuff", it changed the type of 'skb->network_header' for saving size, it needs additional improvement. The related warning (make EXTRA_CFLAGS=3D-W ARCH=3Dm68k allmodconfig): arch/m68k/include/asm/string.h:61:14: note: expected =91__kernel_size= _t=92 but argument is of type =91sk_buff_data_t=92 in "net/netfilter/nf_nat_helper.c" 91 /* Frobs data inside this packet, which is linear. */ 92 static void mangle_contents(struct sk_buff *skb, 93 unsigned int dataoff, 94 unsigned int match_offset, 95 unsigned int match_len, 96 const char *rep_buffer, 97 unsigned int rep_len) 98 { 99 unsigned char *data; 100=20 101 BUG_ON(skb_is_nonlinear(skb)); 102 data =3D skb_network_header(skb) + dataoff; 103=20 104 /* move post-replacement */ 105 memmove(data + match_offset + rep_len, 106 data + match_offset + match_len, 107 skb->tail - (skb->network_header + dataoff + 108 match_offset + match_len)); 109=20 in "include/linux/skbuff.h": 409 struct sk_buff { 410 /* These two members must be first. */ 411 struct sk_buff *next; 412 struct sk_buff *prev; 413=20 414 ktime_t tstamp; 415=20 416 struct sock *sk; 417 struct net_device *dev; 418=20 ... 515 __be16 inner_protocol; 516 __u16 inner_transport_header; 517 __u16 inner_network_header; 518 __u16 inner_mac_header; 519 __u16 transport_header; 520 __u16 network_header; 521 __u16 mac_header; 522 /* These elements must be at the end, see alloc_skb() for = details. */ 523 sk_buff_data_t tail; 524 sk_buff_data_t end; 525 unsigned char *head, 526 *data; 527 unsigned int truesize; 528 atomic_t users; 529 }; 530=20