From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_RED, USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8EE67C433DB for ; Mon, 28 Dec 2020 04:21:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 51EFD221F0 for ; Mon, 28 Dec 2020 04:21:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726323AbgL1EU1 (ORCPT ); Sun, 27 Dec 2020 23:20:27 -0500 Received: from mailgw01.mediatek.com ([210.61.82.183]:59990 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726167AbgL1EU0 (ORCPT ); Sun, 27 Dec 2020 23:20:26 -0500 X-UUID: 22f4a0dbc6904c20a40138dc987cf8d1-20201228 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:MIME-Version:Content-Type:References:In-Reply-To:Date:CC:To:From:Subject:Message-ID; bh=pa5xLy2qDxc+uq3HbpERterwMGHDaoImzt4/agoCKIs=; b=HtptWxBrQ8MGZXxYv0F2Z9K45XJBqWwDkHZX9whs/LgnO9+lpat0uip8Y0+2kYFFlJ1Y8VKb9oVKUhh47CRZxVqr0Eyp2Fv+/mZ8KDPJsMBbhLqmirLkjcN8XwM55GYdypNVzQV5DsdeWqq+0pe4HQtBiWbPpW2fzdiCmoQLD64=; X-UUID: 22f4a0dbc6904c20a40138dc987cf8d1-20201228 Received: from mtkcas10.mediatek.inc [(172.21.101.39)] by mailgw01.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.14 Build 0819 with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1027952524; Mon, 28 Dec 2020 12:19:37 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs01n2.mediatek.inc (172.21.101.79) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Mon, 28 Dec 2020 12:20:37 +0800 Received: from [172.21.84.99] (172.21.84.99) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Mon, 28 Dec 2020 12:20:37 +0800 Message-ID: <1609129169.6472.1.camel@mtksdccf07> Subject: Re: BUG: unable to handle kernel NULL pointer dereference in call_rcu From: Walter Wu To: Dmitry Vyukov CC: Andrew Morton , Andrey Konovalov , syzbot , Alexey Dobriyan , LKML , Waiman Long , Stephen Rothwell , syzkaller-bugs , Vasily Averin , Andrey Ryabinin , "Alexander Potapenko" Date: Mon, 28 Dec 2020 12:19:29 +0800 In-Reply-To: References: <0000000000005ccf1b05b7665adc@google.com> <20201227114534.1b3f407caaf9ec0e821f56f4@linux-foundation.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 MIME-Version: 1.0 X-TM-SNTS-SMTP: A66264A3B3863547C86EAA5E7BFB314FCE050F66B8DEA2AA5BE81D57E7DE73512000:8 X-MTK: N Content-Transfer-Encoding: base64 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org T24gU3VuLCAyMDIwLTEyLTI3IGF0IDIwOjUxICswMTAwLCBEbWl0cnkgVnl1a292IHdyb3RlOg0K PiAvXC9cL1wvXE9uIFN1biwgRGVjIDI3LCAyMDIwIGF0IDg6NDUgUE0gQW5kcmV3IE1vcnRvbg0K PiA8YWtwbUBsaW51eC1mb3VuZGF0aW9uLm9yZz4gd3JvdGU6DQo+ID4NCj4gPiAoY2MgS0FTQU4g ZGV2ZWxvcGVycykNCj4gPg0KPiA+IE9uIFNhdCwgMjYgRGVjIDIwMjAgMTU6MjU6MTQgLTA4MDAg c3l6Ym90IDxzeXpib3QrOWQzZWRlNzIzYmRjNTg1NTNmMTNAc3l6a2FsbGVyLmFwcHNwb3RtYWls LmNvbT4gd3JvdGU6DQo+ID4NCj4gPiA+IEhlbGxvLA0KPiA+ID4NCj4gPiA+IHN5emJvdCBmb3Vu ZCB0aGUgZm9sbG93aW5nIGlzc3VlIG9uOg0KPiA+ID4NCj4gPiA+IEhFQUQgY29tbWl0OiAgICA2 MTRjYjU4OSBNZXJnZSB0YWcgJ2FjcGktNS4xMS1yYzEtMicgb2YgZ2l0Oi8vZ2l0Lmtlcm5lbC5v Li4NCj4gPiA+IGdpdCB0cmVlOiAgICAgICB1cHN0cmVhbQ0KPiA+ID4gY29uc29sZSBvdXRwdXQ6 IGh0dHBzOi8vc3l6a2FsbGVyLmFwcHNwb3QuY29tL3gvbG9nLnR4dD94PTEwYTgyYTUwZDAwMDAw DQo+ID4gPiBrZXJuZWwgY29uZmlnOiAgaHR0cHM6Ly9zeXprYWxsZXIuYXBwc3BvdC5jb20veC8u Y29uZmlnP3g9YmY1MTllMWU5NjE5MTU3Ng0KPiA+ID4gZGFzaGJvYXJkIGxpbms6IGh0dHBzOi8v c3l6a2FsbGVyLmFwcHNwb3QuY29tL2J1Zz9leHRpZD05ZDNlZGU3MjNiZGM1ODU1M2YxMw0KPiA+ ID4gY29tcGlsZXI6ICAgICAgIGdjYyAoR0NDKSAxMC4xLjAtc3l6IDIwMjAwNTA3DQo+ID4gPiBz eXogcmVwcm86ICAgICAgaHR0cHM6Ly9zeXprYWxsZXIuYXBwc3BvdC5jb20veC9yZXByby5zeXo/ eD0xMTgzMGU5MzUwMDAwMA0KPiA+ID4gQyByZXByb2R1Y2VyOiAgIGh0dHBzOi8vc3l6a2FsbGVy LmFwcHNwb3QuY29tL3gvcmVwcm8uYz94PTEzZDkyMDU3NTAwMDAwDQo+ID4gPg0KPiA+ID4gSU1Q T1JUQU5UOiBpZiB5b3UgZml4IHRoZSBpc3N1ZSwgcGxlYXNlIGFkZCB0aGUgZm9sbG93aW5nIHRh ZyB0byB0aGUgY29tbWl0Og0KPiA+ID4gUmVwb3J0ZWQtYnk6IHN5emJvdCs5ZDNlZGU3MjNiZGM1 ODU1M2YxM0BzeXprYWxsZXIuYXBwc3BvdG1haWwuY29tDQo+ID4gPg0KPiA+ID4gQlVHOiBrZXJu ZWwgTlVMTCBwb2ludGVyIGRlcmVmZXJlbmNlLCBhZGRyZXNzOiAwMDAwMDAwMDAwMDAwMDA4DQo+ ID4gPiAjUEY6IHN1cGVydmlzb3IgcmVhZCBhY2Nlc3MgaW4ga2VybmVsIG1vZGUNCj4gPiA+ICNQ RjogZXJyb3JfY29kZSgweDAwMDApIC0gbm90LXByZXNlbnQgcGFnZQ0KPiA+ID4gUEdEIDJkOTkz MDY3IFA0RCAyZDk5MzA2NyBQVUQgMTlhM2MwNjcgUE1EIDANCj4gPiA+IE9vcHM6IDAwMDAgWyMx XSBQUkVFTVBUIFNNUCBLQVNBTg0KPiA+ID4gQ1BVOiAxIFBJRDogMzg1MiBDb21tOiBrd29ya2Vy LzE6MiBOb3QgdGFpbnRlZCA1LjEwLjAtc3l6a2FsbGVyICMwDQo+ID4gPiBIYXJkd2FyZSBuYW1l OiBHb29nbGUgR29vZ2xlIENvbXB1dGUgRW5naW5lL0dvb2dsZSBDb21wdXRlIEVuZ2luZSwgQklP UyBHb29nbGUgMDEvMDEvMjAxMQ0KPiA+ID4gV29ya3F1ZXVlOiBldmVudHMgZnJlZV9pcGMNCj4g PiA+IFJJUDogMDAxMDprYXNhbl9yZWNvcmRfYXV4X3N0YWNrKzB4NzcvMHhiMCBtbS9rYXNhbi9n ZW5lcmljLmM6MzQxDQo+IA0KPiArV2FsdGVyLCBBbmRyZXkNCj4gDQo+IHZvaWQga2FzYW5fcmVj b3JkX2F1eF9zdGFjayh2b2lkICphZGRyKQ0KPiB7DQo+ICAgICAuLi4NCj4gICAgIGFsbG9jX21l dGEgPSBrYXNhbl9nZXRfYWxsb2NfbWV0YShjYWNoZSwgb2JqZWN0KTsNCj4gICAgIGFsbG9jX21l dGEtPmF1eF9zdGFja1sxXSA9IGFsbG9jX21ldGEtPmF1eF9zdGFja1swXTsNCj4gDQo+IC9cL1wv XC9cL1wvXC9cL1wvXC9cL1wvXC9cL1wvXC9cL1wvXC9cL1wvXC9cDQo+IEl0IGNyYXNoZXMgb24g TlVMTCBkZXJlZiBoZXJlLCBJIGFzc3VtZSBhbGxvY19tZXRhIGlzIE5VTEwuIFdlIG1heSBub3QN Cj4gaGF2ZSBpdCBmb3Igc29tZSBzbGFicy4gRG8gd2UgbWlzcyBhIE5VTEwgY2hlY2sgaGVyZT8N Cj4gDQpIaSBEbWl0cnksDQoNClllcywgSSB3aWxsIHNlbmQgYSBwYXRjaCB0byBmaXggaXQuDQoN ClRoYW5rcyBmb3IgeW91ciBzdWdnZXN0aW9uLg0KDQpXYWx0ZXINCg0KPiANCj4gDQo+IA0KPiA+ ID4gQ29kZTogNDggZjcgZmUgOGIgNDcgMjQgNDkgODkgZjAgNDggMjkgZDMgOGQgNzAgZmYgNDEg MGYgYWYgZjAgNDggMDEgY2UgNDggMzkgZjMgNDggMGYgNDYgZjMgZTggODEgZTkgZmYgZmYgYmYg MDAgMDggMDAgMDAgNDggODkgYzMgPDhiPiA0MCAwOCA4OSA0MyAwYyBlOCAxZSBlNiBmZiBmZiA4 OSA0MyAwOCA1YiBjMyA0OCA4YiA1MCAwOCA0OCBjNw0KPiA+ID4gUlNQOiAwMDE4OmZmZmZjOTAw MDJlNmZhZTggRUZMQUdTOiAwMDAxMDA0Ng0KPiA+ID4gUkFYOiAwMDAwMDAwMDAwMDAwMDAwIFJC WDogMDAwMDAwMDAwMDAwMDAwMCBSQ1g6IGZmZmY4ODgwMzk4MDAwMDANCj4gPiA+IFJEWDogMDAw MDAwMDAwMDAwMDA3OCBSU0k6IGZmZmY4ODgwMzk4MDAwMDAgUkRJOiAwMDAwMDAwMDAwMDAwODAw DQo+ID4gPiBSQlA6IGZmZmZmZmZmODM3ZWYzYTAgUjA4OiAwMDAwMDAwMDAwNDAwMDAwIFIwOTog MDAwMDAwMDAwMDAwMDAyZQ0KPiA+ID4gUjEwOiBmZmZmZmZmZjgxMzJiN2VhIFIxMTogMDAwMDAw MDAwMDAwMDAzZiBSMTI6IDAwMDAwMDAwMDAwMzViNDANCj4gPiA+IFIxMzogZmZmZjg4ODAzOTgw MDA4OCBSMTQ6IGZmZmZjOTAwMDJlNmZjMDggUjE1OiAwMDAwMDAwMDAwMDAwMjAwDQo+ID4gPiBG UzogIDAwMDAwMDAwMDAwMDAwMDAoMDAwMCkgR1M6ZmZmZjg4ODBiOWQwMDAwMCgwMDAwKSBrbmxH UzowMDAwMDAwMDAwMDAwMDAwDQo+ID4gPiBDUzogIDAwMTAgRFM6IDAwMDAgRVM6IDAwMDAgQ1Iw OiAwMDAwMDAwMDgwMDUwMDMzDQo+ID4gPiBDUjI6IDAwMDAwMDAwMDAwMDAwMDggQ1IzOiAwMDAw MDAwMDExODQxMDAwIENSNDogMDAwMDAwMDAwMDE1MDZlMA0KPiA+ID4gRFIwOiAwMDAwMDAwMDAw MDAwMDAwIERSMTogMDAwMDAwMDAwMDAwMDAwMCBEUjI6IDAwMDAwMDAwMDAwMDAwMDANCj4gPiA+ IERSMzogMDAwMDAwMDAwMDAwMDAwMCBEUjY6IDAwMDAwMDAwZmZmZTBmZjAgRFI3OiAwMDAwMDAw MDAwMDAwNDAwDQo+ID4gPiBDYWxsIFRyYWNlOg0KPiA+ID4gIF9fY2FsbF9yY3Uga2VybmVsL3Jj dS90cmVlLmM6Mjk2NSBbaW5saW5lXQ0KPiA+ID4gIGNhbGxfcmN1KzB4YmIvMHg3MTAga2VybmVs L3JjdS90cmVlLmM6MzAzOA0KPiA+ID4gIGlwY19yY3VfcHV0cmVmKzB4ODMvMHhiMCBpcGMvdXRp bC5jOjUwNQ0KPiA+ID4gIGZyZWVhcnkrMHgxMzljLzB4MWIzMCBpcGMvc2VtLmM6MTE4OA0KPiA+ ID4gIGZyZWVfaXBjcysweDk4LzB4MWUwIGlwYy9uYW1lc3BhY2UuYzoxMTINCj4gPiA+ICBzZW1f ZXhpdF9ucysweDFiLzB4NDAgaXBjL3NlbS5jOjI2MA0KPiA+ID4gIGZyZWVfaXBjX25zIGlwYy9u YW1lc3BhY2UuYzoxMjQgW2lubGluZV0NCj4gPiA+ICBmcmVlX2lwYysweGY4LzB4MjAwIGlwYy9u YW1lc3BhY2UuYzoxNDENCj4gPiA+ICBwcm9jZXNzX29uZV93b3JrKzB4OThkLzB4MTYzMCBrZXJu ZWwvd29ya3F1ZXVlLmM6MjI3NQ0KPiA+ID4gIHdvcmtlcl90aHJlYWQrMHg2NGMvMHgxMTIwIGtl cm5lbC93b3JrcXVldWUuYzoyNDIxDQo+ID4gPiAga3RocmVhZCsweDNiMS8weDRhMCBrZXJuZWwv a3RocmVhZC5jOjI5Mg0KPiA+ID4gIHJldF9mcm9tX2ZvcmsrMHgxZi8weDMwIGFyY2gveDg2L2Vu dHJ5L2VudHJ5XzY0LlM6Mjk2DQo+ID4gPiBNb2R1bGVzIGxpbmtlZCBpbjoNCj4gPiA+IENSMjog MDAwMDAwMDAwMDAwMDAwOA0KPiA+ID4gLS0tWyBlbmQgdHJhY2UgMjhkYzA5M2U2MWQ0NGRjMiBd LS0tDQo+ID4gPiBSSVA6IDAwMTA6a2FzYW5fcmVjb3JkX2F1eF9zdGFjaysweDc3LzB4YjAgbW0v a2FzYW4vZ2VuZXJpYy5jOjM0MQ0KPiA+ID4gQ29kZTogNDggZjcgZmUgOGIgNDcgMjQgNDkgODkg ZjAgNDggMjkgZDMgOGQgNzAgZmYgNDEgMGYgYWYgZjAgNDggMDEgY2UgNDggMzkgZjMgNDggMGYg NDYgZjMgZTggODEgZTkgZmYgZmYgYmYgMDAgMDggMDAgMDAgNDggODkgYzMgPDhiPiA0MCAwOCA4 OSA0MyAwYyBlOCAxZSBlNiBmZiBmZiA4OSA0MyAwOCA1YiBjMyA0OCA4YiA1MCAwOCA0OCBjNw0K PiA+ID4gUlNQOiAwMDE4OmZmZmZjOTAwMDJlNmZhZTggRUZMQUdTOiAwMDAxMDA0Ng0KPiA+ID4g UkFYOiAwMDAwMDAwMDAwMDAwMDAwIFJCWDogMDAwMDAwMDAwMDAwMDAwMCBSQ1g6IGZmZmY4ODgw Mzk4MDAwMDANCj4gPiA+IFJEWDogMDAwMDAwMDAwMDAwMDA3OCBSU0k6IGZmZmY4ODgwMzk4MDAw MDAgUkRJOiAwMDAwMDAwMDAwMDAwODAwDQo+ID4gPiBSQlA6IGZmZmZmZmZmODM3ZWYzYTAgUjA4 OiAwMDAwMDAwMDAwNDAwMDAwIFIwOTogMDAwMDAwMDAwMDAwMDAyZQ0KPiA+ID4gUjEwOiBmZmZm ZmZmZjgxMzJiN2VhIFIxMTogMDAwMDAwMDAwMDAwMDAzZiBSMTI6IDAwMDAwMDAwMDAwMzViNDAN Cj4gPiA+IFIxMzogZmZmZjg4ODAzOTgwMDA4OCBSMTQ6IGZmZmZjOTAwMDJlNmZjMDggUjE1OiAw MDAwMDAwMDAwMDAwMjAwDQo+ID4gPiBGUzogIDAwMDAwMDAwMDAwMDAwMDAoMDAwMCkgR1M6ZmZm Zjg4ODBiOWQwMDAwMCgwMDAwKSBrbmxHUzowMDAwMDAwMDAwMDAwMDAwDQo+ID4gPiBDUzogIDAw MTAgRFM6IDAwMDAgRVM6IDAwMDAgQ1IwOiAwMDAwMDAwMDgwMDUwMDMzDQo+ID4gPiBDUjI6IDAw MDAwMDAwMDAwMDAwMDggQ1IzOiAwMDAwMDAwMDExODQxMDAwIENSNDogMDAwMDAwMDAwMDE1MDZl MA0KPiA+ID4gRFIwOiAwMDAwMDAwMDAwMDAwMDAwIERSMTogMDAwMDAwMDAwMDAwMDAwMCBEUjI6 IDAwMDAwMDAwMDAwMDAwMDANCj4gPiA+IERSMzogMDAwMDAwMDAwMDAwMDAwMCBEUjY6IDAwMDAw MDAwZmZmZTBmZjAgRFI3OiAwMDAwMDAwMDAwMDAwNDAwDQo+ID4gPg0KPiA+ID4NCj4gPiA+IC0t LQ0KPiA+ID4gVGhpcyByZXBvcnQgaXMgZ2VuZXJhdGVkIGJ5IGEgYm90LiBJdCBtYXkgY29udGFp biBlcnJvcnMuDQo+ID4gPiBTZWUgaHR0cHM6Ly9nb28uZ2wvdHBzbUVKIGZvciBtb3JlIGluZm9y bWF0aW9uIGFib3V0IHN5emJvdC4NCj4gPiA+IHN5emJvdCBlbmdpbmVlcnMgY2FuIGJlIHJlYWNo ZWQgYXQgc3l6a2FsbGVyQGdvb2dsZWdyb3Vwcy5jb20uDQo+ID4gPg0KPiA+ID4gc3l6Ym90IHdp bGwga2VlcCB0cmFjayBvZiB0aGlzIGlzc3VlLiBTZWU6DQo+ID4gPiBodHRwczovL2dvby5nbC90 cHNtRUojc3RhdHVzIGZvciBob3cgdG8gY29tbXVuaWNhdGUgd2l0aCBzeXpib3QuDQo+ID4gPiBz eXpib3QgY2FuIHRlc3QgcGF0Y2hlcyBmb3IgdGhpcyBpc3N1ZSwgZm9yIGRldGFpbHMgc2VlOg0K PiA+ID4gaHR0cHM6Ly9nb28uZ2wvdHBzbUVKI3Rlc3RpbmctcGF0Y2hlcw0KDQo=