From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752645AbdCFCMr (ORCPT ); Sun, 5 Mar 2017 21:12:47 -0500 Received: from mail-wm0-f68.google.com ([74.125.82.68]:36235 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752414AbdCFCMp (ORCPT ); Sun, 5 Mar 2017 21:12:45 -0500 MIME-Version: 1.0 In-Reply-To: References:

From: Cong Wang Date: Sun, 5 Mar 2017 18:04:46 -0800 Message-ID: Subject: Re: net/ipv4: deadlock in ip_ra_control To: Dmitry Vyukov Cc: David Miller , Alexey Kuznetsov , James Morris , Hideaki YOSHIFUJI , Patrick McHardy , Eric Dumazet , netdev , LKML , syzkaller Content-Type: multipart/mixed; boundary=001a114b09c004eba5054a0653d9 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --001a114b09c004eba5054a0653d9 Content-Type: text/plain; charset=UTF-8 On Fri, Mar 3, 2017 at 10:43 AM, Dmitry Vyukov wrote: > On Thu, Mar 2, 2017 at 10:40 AM, Dmitry Vyukov wrote: >> On Wed, Mar 1, 2017 at 6:18 PM, Cong Wang wrote: >>> On Wed, Mar 1, 2017 at 2:44 AM, Dmitry Vyukov wrote: >>>> Hello, >>>> >>>> I've got the following deadlock report while running syzkaller fuzzer >>>> on linux-next/51788aebe7cae79cb334ad50641347465fc188fd: >>>> >>>> ====================================================== >>>> [ INFO: possible circular locking dependency detected ] >>>> 4.10.0-next-20170301+ #1 Not tainted >>>> ------------------------------------------------------- >>>> syz-executor1/3394 is trying to acquire lock: >>>> (sk_lock-AF_INET){+.+.+.}, at: [] lock_sock >>>> include/net/sock.h:1460 [inline] >>>> (sk_lock-AF_INET){+.+.+.}, at: [] >>>> do_ip_setsockopt.isra.12+0x21c/0x3540 net/ipv4/ip_sockglue.c:652 >>>> >>>> but task is already holding lock: >>>> (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 >>>> net/core/rtnetlink.c:70 >>>> >>>> which lock already depends on the new lock. >>>> >>>> >>>> the existing dependency chain (in reverse order) is: >>>> >>>> -> #1 (rtnl_mutex){+.+.+.}: >>>> validate_chain kernel/locking/lockdep.c:2265 [inline] >>>> __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3338 >>>> lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3753 >>>> __mutex_lock_common kernel/locking/mutex.c:754 [inline] >>>> __mutex_lock+0x172/0x1730 kernel/locking/mutex.c:891 >>>> mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:906 >>>> rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 >>>> mrtsock_destruct+0x86/0x2c0 net/ipv4/ipmr.c:1281 >>>> ip_ra_control+0x459/0x600 net/ipv4/ip_sockglue.c:372 >>>> do_ip_setsockopt.isra.12+0x1064/0x3540 net/ipv4/ip_sockglue.c:1161 >>>> ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 >>>> raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:839 >>>> sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2725 >>>> SYSC_setsockopt net/socket.c:1786 [inline] >>>> SyS_setsockopt+0x25c/0x390 net/socket.c:1765 >>>> entry_SYSCALL_64_fastpath+0x1f/0xc2 >>>> >>>> -> #0 (sk_lock-AF_INET){+.+.+.}: >>>> check_prev_add kernel/locking/lockdep.c:1828 [inline] >>>> check_prevs_add+0xa8f/0x19f0 kernel/locking/lockdep.c:1938 >>>> validate_chain kernel/locking/lockdep.c:2265 [inline] >>>> __lock_acquire+0x2149/0x3430 kernel/locking/lockdep.c:3338 >>>> lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3753 >>>> lock_sock_nested+0xcb/0x120 net/core/sock.c:2530 >>>> lock_sock include/net/sock.h:1460 [inline] >>>> do_ip_setsockopt.isra.12+0x21c/0x3540 net/ipv4/ip_sockglue.c:652 >>>> ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1264 >>>> tcp_setsockopt+0x82/0xd0 net/ipv4/tcp.c:2721 >>>> sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2725 >>>> SYSC_setsockopt net/socket.c:1786 [inline] >>>> SyS_setsockopt+0x25c/0x390 net/socket.c:1765 >>>> entry_SYSCALL_64_fastpath+0x1f/0xc2 >>>> >>> >>> Please try the attached patch (compile only). >> >> >> Pushed the patch to the bots. >> Thanks > > > This patch triggers: Ah, update the patch to fix this. --001a114b09c004eba5054a0653d9 Content-Type: text/plain; charset=US-ASCII; name="ip-router-alert.diff" Content-Disposition: attachment; filename="ip-router-alert.diff" Content-Transfer-Encoding: base64 X-Attachment-Id: f_izxgriv60 ZGlmZiAtLWdpdCBhL25ldC9pcHY0L2lwX3NvY2tnbHVlLmMgYi9uZXQvaXB2NC9pcF9zb2NrZ2x1 ZS5jCmluZGV4IGViZDk1M2IuLmJkYTMxOGEgMTAwNjQ0Ci0tLSBhL25ldC9pcHY0L2lwX3NvY2tn bHVlLmMKKysrIGIvbmV0L2lwdjQvaXBfc29ja2dsdWUuYwpAQCAtNTkxLDYgKzU5MSw3IEBAIHN0 YXRpYyBib29sIHNldHNvY2tvcHRfbmVlZHNfcnRubChpbnQgb3B0bmFtZSkKIAljYXNlIE1DQVNU X0xFQVZFX0dST1VQOgogCWNhc2UgTUNBU1RfTEVBVkVfU09VUkNFX0dST1VQOgogCWNhc2UgTUNB U1RfVU5CTE9DS19TT1VSQ0U6CisJY2FzZSBJUF9ST1VURVJfQUxFUlQ6CiAJCXJldHVybiB0cnVl OwogCX0KIAlyZXR1cm4gZmFsc2U7CmRpZmYgLS1naXQgYS9uZXQvaXB2NC9pcG1yLmMgYi9uZXQv aXB2NC9pcG1yLmMKaW5kZXggYzAzMTdjOS4uYjAzNmU4NSAxMDA2NDQKLS0tIGEvbmV0L2lwdjQv aXBtci5jCisrKyBiL25ldC9pcHY0L2lwbXIuYwpAQCAtMTI3OCw3ICsxMjc4LDcgQEAgc3RhdGlj IHZvaWQgbXJ0c29ja19kZXN0cnVjdChzdHJ1Y3Qgc29jayAqc2spCiAJc3RydWN0IG5ldCAqbmV0 ID0gc29ja19uZXQoc2spOwogCXN0cnVjdCBtcl90YWJsZSAqbXJ0OwogCi0JcnRubF9sb2NrKCk7 CisJQVNTRVJUX1JUTkwoKTsKIAlpcG1yX2Zvcl9lYWNoX3RhYmxlKG1ydCwgbmV0KSB7CiAJCWlm IChzayA9PSBydG5sX2RlcmVmZXJlbmNlKG1ydC0+bXJvdXRlX3NrKSkgewogCQkJSVBWNF9ERVZD T05GX0FMTChuZXQsIE1DX0ZPUldBUkRJTkcpLS07CkBAIC0xMjg5LDcgKzEyODksNiBAQCBzdGF0 aWMgdm9pZCBtcnRzb2NrX2Rlc3RydWN0KHN0cnVjdCBzb2NrICpzaykKIAkJCW1yb3V0ZV9jbGVh bl90YWJsZXMobXJ0LCBmYWxzZSk7CiAJCX0KIAl9Ci0JcnRubF91bmxvY2soKTsKIH0KIAogLyog U29ja2V0IG9wdGlvbnMgYW5kIHZpcnR1YWwgaW50ZXJmYWNlIG1hbmlwdWxhdGlvbi4gVGhlIHdo b2xlCkBAIC0xMzUzLDEzICsxMzUyLDggQEAgaW50IGlwX21yb3V0ZV9zZXRzb2Nrb3B0KHN0cnVj dCBzb2NrICpzaywgaW50IG9wdG5hbWUsIGNoYXIgX191c2VyICpvcHR2YWwsCiAJCWlmIChzayAh PSByY3VfYWNjZXNzX3BvaW50ZXIobXJ0LT5tcm91dGVfc2spKSB7CiAJCQlyZXQgPSAtRUFDQ0VT OwogCQl9IGVsc2UgewotCQkJLyogV2UgbmVlZCB0byB1bmxvY2sgaGVyZSBiZWNhdXNlIG1ydHNv Y2tfZGVzdHJ1Y3QgdGFrZXMKLQkJCSAqIGNhcmUgb2YgcnRubCBpdHNlbGYgYW5kIHdlIGNhbid0 IGNoYW5nZSB0aGF0IGR1ZSB0bwotCQkJICogdGhlIElQX1JPVVRFUl9BTEVSVCBzZXRzb2Nrb3B0 IHdoaWNoIHJ1bnMgd2l0aG91dCBpdC4KLQkJCSAqLwotCQkJcnRubF91bmxvY2soKTsKIAkJCXJl dCA9IGlwX3JhX2NvbnRyb2woc2ssIDAsIE5VTEwpOwotCQkJZ290byBvdXQ7CisJCQlnb3RvIG91 dF91bmxvY2s7CiAJCX0KIAkJYnJlYWs7CiAJY2FzZSBNUlRfQUREX1ZJRjoKQEAgLTE0NzAsNyAr MTQ2NCw2IEBAIGludCBpcF9tcm91dGVfc2V0c29ja29wdChzdHJ1Y3Qgc29jayAqc2ssIGludCBv cHRuYW1lLCBjaGFyIF9fdXNlciAqb3B0dmFsLAogCX0KIG91dF91bmxvY2s6CiAJcnRubF91bmxv Y2soKTsKLW91dDoKIAlyZXR1cm4gcmV0OwogfQogCmRpZmYgLS1naXQgYS9uZXQvaXB2NC9yYXcu YyBiL25ldC9pcHY0L3Jhdy5jCmluZGV4IDgxMTllMWYuLjlkOTQzOTcgMTAwNjQ0Ci0tLSBhL25l dC9pcHY0L3Jhdy5jCisrKyBiL25ldC9pcHY0L3Jhdy5jCkBAIC02ODIsNyArNjgyLDkgQEAgc3Rh dGljIHZvaWQgcmF3X2Nsb3NlKHN0cnVjdCBzb2NrICpzaywgbG9uZyB0aW1lb3V0KQogCS8qCiAJ ICogUmF3IHNvY2tldHMgbWF5IGhhdmUgZGlyZWN0IGtlcm5lbCByZWZlcmVuY2VzLiBLaWxsIHRo ZW0uCiAJICovCisJcnRubF9sb2NrKCk7CiAJaXBfcmFfY29udHJvbChzaywgMCwgTlVMTCk7CisJ cnRubF91bmxvY2soKTsKIAogCXNrX2NvbW1vbl9yZWxlYXNlKHNrKTsKIH0K --001a114b09c004eba5054a0653d9--