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=-5.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 CC5CDC11D02 for ; Thu, 20 Feb 2020 06:31:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AF08124656 for ; Thu, 20 Feb 2020 06:31:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726856AbgBTGbP (ORCPT ); Thu, 20 Feb 2020 01:31:15 -0500 Received: from mail-io1-f69.google.com ([209.85.166.69]:56549 "EHLO mail-io1-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726735AbgBTGbP (ORCPT ); Thu, 20 Feb 2020 01:31:15 -0500 Received: by mail-io1-f69.google.com with SMTP id d13so1905326ioo.23 for ; Wed, 19 Feb 2020 22:31:14 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=DDqMJ8JPj7oJO/ZR8xGUg6VFAFuonxwUf5QT8gnpMlI=; b=G4QXcfE1XumJmzm5oXWavLfOePbtPDaf0EcLtJUbT0tw4B0H3lGDwjguhP3Tv/Qstq 5hSdqUd1k+EYWuF1TFOgbI2UixODdq4sEoHjeeLYzEVeM2DWaRTk4ORQiWuhBZc70Zz+ kiLti+gsSrEBrVu6zRK7Q2vUKl0tx57bgdTtz/qSwC/AxASqjLOFQU33G23kmH+arQlC tDCsNdxTrAcKDxvGUt493OyAnYiC7rDn3jbAT8D4iy8g8iIaI6+u7wkfOtMG+TGiwrUy KLFLcUnDvZ0+VSqUr/M1E7zCXcjdTgqgxS0ji6SIYMejIR/+NCgLY+/tGfKnaqCU1wYA yhXg== X-Gm-Message-State: APjAAAXQ/pdeG+vNZWl6XwC+7VJWQM3wf4jSabTZ9Vcx2AAbaqNnSV2a naHbQjdLFnMCvcLymofg8ggNd9u3XwtWM+k3kaHTwtjbN8ye X-Google-Smtp-Source: APXvYqxOsNiTKh+qdqttr1Rz5Xoag30BA+Qf5UFs3ZfyNMV1nBh7iGpymuj0iWTB8mx5mFnbL62z472NbkKQFR/ecoPKcwCxKaZz MIME-Version: 1.0 X-Received: by 2002:a92:cb8c:: with SMTP id z12mr26095480ilo.5.1582180274590; Wed, 19 Feb 2020 22:31:14 -0800 (PST) Date: Wed, 19 Feb 2020 22:31:14 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000003cdd26059efc0db3@google.com> Subject: KASAN: null-ptr-deref Write in kcm_tx_work From: syzbot To: andriin@fb.com, ast@kernel.org, bpf@vger.kernel.org, daniel@iogearbox.net, davem@davemloft.net, edumazet@google.com, jslaby@suse.cz, kafai@fb.com, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, songliubraving@fb.com, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, willy@infradead.org, yhs@fb.com Content-Type: text/plain; charset="UTF-8" Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 2019fc96 Merge git://git.kernel.org/pub/scm/linux/kernel/g.. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=159f2701e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=735296e4dd620b10 dashboard link: https://syzkaller.appspot.com/bug?extid=867331f5ea7690d840b4 compiler: gcc (GCC) 9.0.0 20181231 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+867331f5ea7690d840b4@syzkaller.appspotmail.com ================================================================== BUG: KASAN: null-ptr-deref in clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline] BUG: KASAN: null-ptr-deref in kcm_tx_work+0x10e/0x170 net/kcm/kcmsock.c:743 Write of size 8 at addr 0000000000000008 by task kworker/u4:4/280 CPU: 0 PID: 280 Comm: kworker/u4:4 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: kkcmd kcm_tx_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 __kasan_report.cold+0x5/0x32 mm/kasan/report.c:510 kasan_report+0x12/0x20 mm/kasan/common.c:641 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 __kasan_check_write+0x14/0x20 mm/kasan/common.c:101 clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline] kcm_tx_work+0x10e/0x170 net/kcm/kcmsock.c:743 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 280 Comm: kworker/u4:4 Tainted: G B 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: kkcmd kcm_tx_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 panic+0x2e3/0x75c kernel/panic.c:221 end_report+0x47/0x4f mm/kasan/report.c:96 __kasan_report.cold+0xe/0x32 mm/kasan/report.c:513 kasan_report+0x12/0x20 mm/kasan/common.c:641 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 __kasan_check_write+0x14/0x20 mm/kasan/common.c:101 clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline] kcm_tx_work+0x10e/0x170 net/kcm/kcmsock.c:743 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Kernel Offset: disabled Rebooting in 86400 seconds.. --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.