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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CE58BC00140 for ; Mon, 8 Aug 2022 13:05:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235594AbiHHNFm (ORCPT ); Mon, 8 Aug 2022 09:05:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243050AbiHHNFg (ORCPT ); Mon, 8 Aug 2022 09:05:36 -0400 Received: from mail-il1-f199.google.com (mail-il1-f199.google.com [209.85.166.199]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 76113BAE for ; Mon, 8 Aug 2022 06:05:35 -0700 (PDT) Received: by mail-il1-f199.google.com with SMTP id n13-20020a056e02140d00b002dfa5464967so5123698ilo.19 for ; Mon, 08 Aug 2022 06:05:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc; bh=n6ROnGRPeHKbMDkjBCI+NrZj8XSZt/pq4k4SlgJSBxA=; b=oBkHWZGuinfPGCcfM/i9XcyJaxuRcL2jONrA+02sJfD5uXYj/ESLM9DOdhH/T4/XPb V/ZCIZdIAd7xAszAJl2fC7edyYRNgTdAt1wuTALwDgMWFo7063s+VGtJ+FNbZC5/Ur/j c/t2suzvf1pTcaxFuenrolFddyrpYDcIiwR2cZa/1uiqCaPV99DxxrV3+Mm/xWbLW2mM Mk2f3wfyMMssbAG7izW7la3yzySENHwAaTNf+U8h/3RCMDMGqRK8F2wePiYom6nev9Zc CcueOoJyq5zBUVPjobPYFXwq2ceGTZs1LKdYk8HBn8AUkVgX79byyDBhvnWAuwMi4Sjg j5PA== X-Gm-Message-State: ACgBeo1onVUR59I2VrBZdJVRhJIyTa10bxleo5McYVIiuOmpux151Lg8 exuECbXqOis+87oAwjvw1NVv8c8fCQFW4Ek+QSSgi1NSi9cB X-Google-Smtp-Source: AA6agR5woTsLLFreeMQmbnK4S0UNyNON4F4diygZs6lq/PrvL8V8SMhBoJr194h34ZCxT1n5sYnsoA5SGioiaEurNxK3ynQ1ebxr MIME-Version: 1.0 X-Received: by 2002:a05:6602:168d:b0:67c:44c3:9ba5 with SMTP id s13-20020a056602168d00b0067c44c39ba5mr7502643iow.190.1659963934890; Mon, 08 Aug 2022 06:05:34 -0700 (PDT) Date: Mon, 08 Aug 2022 06:05:34 -0700 In-Reply-To: <000000000000b7352e05e5b61f84@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000ade42905e5ba78e0@google.com> Subject: Re: [syzbot] BUG: unable to handle kernel NULL pointer dereference in gsmld_receive_buf From: syzbot To: gregkh@linuxfoundation.org, jirislaby@kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org syzbot has found a reproducer for the following issue on: HEAD commit: ca688bff68bc Add linux-next specific files for 20220808 git tree: linux-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=14a27066080000 kernel config: https://syzkaller.appspot.com/x/.config?x=4c20e006003cdecb dashboard link: https://syzkaller.appspot.com/bug?extid=e3563f0c94e188366dbb compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=164eb3ca080000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17327ce1080000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e3563f0c94e188366dbb@syzkaller.appspotmail.com BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 74c90067 P4D 74c90067 PUD 74c53067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 3606 Comm: syz-executor237 Not tainted 5.19.0-next-20220808-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffffc9000387fcf0 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff88801bbdf000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88801bbdf000 RBP: ffffc9000387fda1 R08: 0000000000000001 R09: 0000000000000004 R10: 0000000000000000 R11: 1ffffffff1ffa9ce R12: 0000000000000001 R13: 0000000000000000 R14: ffffc9000387fd90 R15: dffffc0000000000 FS: 0000555556e8d300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000001c7e0000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: gsmld_receive_buf+0x1c2/0x2f0 drivers/tty/n_gsm.c:2861 tiocsti drivers/tty/tty_io.c:2293 [inline] tty_ioctl+0xa75/0x15d0 drivers/tty/tty_io.c:2692 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f76c0e5eb59 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe9a4f7c48 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f76c0e5eb59 RDX: 0000000020000040 RSI: 0000000000005412 RDI: 0000000000000004 RBP: 00007f76c0e22d00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f76c0e22d90 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: CR2: 0000000000000000 ---[ end trace 0000000000000000 ]--- RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffffc9000387fcf0 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff88801bbdf000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88801bbdf000 RBP: ffffc9000387fda1 R08: 0000000000000001 R09: 0000000000000004 R10: 0000000000000000 R11: 1ffffffff1ffa9ce R12: 0000000000000001 R13: 0000000000000000 R14: ffffc9000387fd90 R15: dffffc0000000000 FS: 0000555556e8d300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000001c7e0000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400