Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760224AbYHEJ0B (ORCPT ); Tue, 5 Aug 2008 05:26:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756942AbYHEJZs (ORCPT ); Tue, 5 Aug 2008 05:25:48 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:51247 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1754896AbYHEJZq (ORCPT ); Tue, 5 Aug 2008 05:25:46 -0400 Message-ID: <48981BB8.9060100@cn.fujitsu.com> Date: Tue, 05 Aug 2008 17:22:00 +0800 From: Gui Jianfeng User-Agent: Thunderbird 2.0.0.5 (Windows/20070716) MIME-Version: 1.0 To: David Miller CC: netdev , linux-kernel@vger.kernel.org Subject: [PATCH 0/3] Fix kernel panic when calling tcp_(v4/v6)_md5_do_lookup Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3425 Lines: 63 If the following packet flow happen, kernel will panic. MathineA MathineB SYN ----------------------> SYN+ACK <---------------------- ACK(bad seq) ----------------------> When a bad seq ACK is received, tcp_v4_md5_do_lookup(skb->sk, ip_hdr(skb)->daddr)) is finally called by tcp_v4_reqsk_send_ack(), but the first parameter(skb->sk) is NULL at that moment, so kernel panic happens. This patch set fix this issue. Below is the OOPS output: [ 302.812793] IP: [] tcp_v4_md5_do_lookup+0x12/0x42 [ 302.817075] Oops: 0000 [#1] SMP [ 302.819815] Modules linked in: ipv6 loop dm_multipath rtc_cmos rtc_core rtc_lib pcspkr pcnet32 mii i2c_piix4 parport_pc i2c_core parport ac button ata_piix libata dm_mod mptspi mptscsih mptbase scsi_transport_spi sd_mod scsi_mod crc_t10dif ext3 jbd mbcache uhci_hcd ohci_hcd ehci_hcd [last unloaded: scsi_wait_scan] [ 302.849946] [ 302.851198] Pid: 0, comm: swapper Not tainted (2.6.27-rc1-guijf #5) [ 302.855184] EIP: 0060:[] EFLAGS: 00010296 CPU: 0 [ 302.858296] EIP is at tcp_v4_md5_do_lookup+0x12/0x42 [ 302.861027] EAX: 0000001e EBX: 00000000 ECX: 00000046 EDX: 00000046 [ 302.864867] ESI: ceb69e00 EDI: 1467a8c0 EBP: cf75f180 ESP: c0792e54 [ 302.868333] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 [ 302.871287] Process swapper (pid: 0, ti=c0792000 task=c0712340 task.ti=c0746000) [ 302.875592] Stack: c06f413a 00000000 cf75f180 ceb69e00 00000000 c05d0d86 000016d0 ceac5400 [ 302.883275] c05d28f8 000016d0 ceb69e00 ceb69e20 681bf6e3 00001000 00000000 0a67a8c0 [ 302.890971] ceac5400 c04250a3 c06f413a c0792eb0 c0792edc cf59a620 cf59a620 cf59a634 [ 302.900140] Call Trace: [ 302.902392] [] tcp_v4_reqsk_send_ack+0x17/0x35 [ 302.907060] [] tcp_check_req+0x156/0x372 [ 302.910082] [] printk+0x14/0x18 [ 302.912868] [] tcp_v4_do_rcv+0x1d3/0x2bf [ 302.917423] [] tcp_v4_rcv+0x563/0x5b9 [ 302.920453] [] ip_local_deliver_finish+0xe8/0x183 [ 302.923865] [] ip_rcv_finish+0x286/0x2a3 [ 302.928569] [] dev_alloc_skb+0x11/0x25 [ 302.931563] [] netif_receive_skb+0x2d6/0x33a [ 302.934914] [] pcnet32_poll+0x333/0x680 [pcnet32] [ 302.938735] [] net_rx_action+0x5c/0xfe [ 302.941792] [] __do_softirq+0x5d/0xc1 [ 302.944788] [] __do_softirq+0x0/0xc1 [ 302.948999] [] do_softirq+0x55/0x88 [ 302.951870] [] handle_fasteoi_irq+0x0/0xa4 [ 302.954986] [] irq_exit+0x35/0x69 [ 302.959081] [] do_IRQ+0x99/0xae [ 302.961896] [] common_interrupt+0x23/0x28 [ 302.966279] [] default_idle+0x2a/0x3d [ 302.969212] [] cpu_idle+0xb2/0xd2 [ 302.972169] ======================= [ 302.974274] Code: fc ff 84 d2 0f 84 df fd ff ff e9 34 fe ff ff 83 c4 0c 5b 5e 5f 5d c3 90 90 57 89 d7 56 53 89 c3 50 68 3a 41 6f c0 e8 e9 55 e5 ff <8b> 93 9c 04 00 00 58 85 d2 59 74 1e 8b 72 10 31 db 31 c9 85 f6 [ 303.011610] EIP: [] tcp_v4_md5_do_lookup+0x12/0x42 SS:ESP 0068:c0792e54 [ 303.018360] Kernel panic - not syncing: Fatal exception in interrupt -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/