From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x225H7tRPi4/rLEM3hry64p/eN0ImHTQt008k/bhWsm5ybtc0WLEWADVphuLN/Y8RhWhrcknM ARC-Seal: i=1; a=rsa-sha256; t=1517410409; cv=none; d=google.com; s=arc-20160816; b=wXiGVfjXwM16OyMYGWXrpTfiWXZjna5suyrSwEPk4NRa5GxCxZ0Qeijq7JR8SYmKHH FmpChm5gt6o/QDr1odlZEZM2/DgitlXeLdKNqe85cd+ducJFQySggaWSsfsRZc3FtMk4 fPV6s3uMprNsibn5qFJ60cQ7oH++YVQIsnyuc3J00pdSDs9JZkFcMik8wffQAmSSnYOH LSCAYQzIWRvIvIJBdb3DDUeCVgDm5wc9QtGMIP2jgUx1rDscdkOLNEqbasZXJfcUo2A9 +vlieNWat4JTT4vo4fwLM/1opxVc0vvWb2+7YAzEEaGY0iKoA75Jb4pi19PLURnFlA9F c58w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:dkim-signature :arc-authentication-results; bh=HrLBoQ/b3JwMEYDQSeHAh3WOnNpEunkEwEwLHKzGRyc=; b=wuSbkL2dZImhQnD6qcz5jEfYHlvnBTsqGpLcZGh50tPlH3KTDWclu7XpdVnNdbikjg xUCPB4tRmwYQIspn24uAjJq8sqQDbA7wu7YbYjTHB75amto8eEJUxilqGMQ/fD+H7+Mv Dva7XdnXM33eyrck9dDZ/8oHVF6rFXeG9AzK/8/Fq/B4q3Edo5RfjEOshXQPlL9q23yN GGGdhz0Avx2zAXUQaM60M8QNLjJlyBBjpMJrCdH+j11C8OB06BNx39OPzNJvq8JVw61P /QrycKNcJ/I7TaCmpi/Aua4VuQ8X6wp19Vz+Xkl5hJB9ap7hL3XDMkqiN46pn816O1Az c3/A== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2017-10-26 header.b=sMQpWBJL; spf=pass (google.com: domain of dan.carpenter@oracle.com designates 156.151.31.85 as permitted sender) smtp.mailfrom=dan.carpenter@oracle.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Authentication-Results: mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2017-10-26 header.b=sMQpWBJL; spf=pass (google.com: domain of dan.carpenter@oracle.com designates 156.151.31.85 as permitted sender) smtp.mailfrom=dan.carpenter@oracle.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Date: Wed, 31 Jan 2018 17:53:09 +0300 From: Dan Carpenter To: Dmitry Vyukov Cc: Eric Biggers , syzbot , devel@driverdev.osuosl.org, Greg Kroah-Hartman , syzkaller-bugs@googlegroups.com, riandrews@android.com, LKML , arve@android.com, Martijn Coenen Subject: Re: kernel BUG at drivers/android/binder_alloc.c:LINE! Message-ID: <20180131145309.ytammrpri5koaj7v@mwanda> References: <94eb2c111b8cc9b724055f4999a7@google.com> <001a1145ee704e6c33055f50798d@google.com> <20180131075947.GG2736@zzz.localdomain> <20180131080843.r4tv775h6cjyvhzb@mwanda> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170609 (1.8.3) X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8790 signatures=668657 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=2 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1801310194 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1585598537470221646?= X-GMAIL-MSGID: =?utf-8?q?1591120138056113387?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Wed, Jan 31, 2018 at 01:00:35PM +0100, Dmitry Vyukov wrote: > On Wed, Jan 31, 2018 at 9:08 AM, Dan Carpenter wrote: > > On Tue, Jan 30, 2018 at 11:59:47PM -0800, Eric Biggers wrote: > >> On Fri, Dec 01, 2017 at 04:22:00PM -0800, syzbot wrote: > >> > syzkaller has found reproducer for the following crash on > >> > 3c1c4ddffb58b9e10b3365764fe59546130b3f32 > >> > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master > >> > compiler: gcc (GCC) 7.1.1 20170620 > >> > .config is attached > >> > Raw console output is attached. > >> > C reproducer is attached > >> > syzkaller reproducer is attached. See https://goo.gl/kgGztJ > >> > for information about syzkaller reproducers > >> > > >> > > >> > binder: 3087:3087 ERROR: BC_REGISTER_LOOPER called without request > >> > binder: 3087:3087 ioctl c0306201 2000dfd0 returned -14 > >> > ------------[ cut here ]------------ > >> > kernel BUG at drivers/android/binder_alloc.c:750! > >> > invalid opcode: 0000 [#1] SMP KASAN > >> > Dumping ftrace buffer: > >> > (ftrace buffer empty) > >> > Modules linked in: > >> > CPU: 0 PID: 1404 Comm: kworker/0:2 Not tainted 4.15.0-rc1+ #203 > >> > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > >> > Google 01/01/2011 > >> > Workqueue: events binder_deferred_func > >> > task: 0000000009b739b6 task.stack: 00000000c1d4442c > >> > RIP: 0010:binder_alloc_deferred_release+0x146/0xa40 > >> > drivers/android/binder_alloc.c:750 > >> > RSP: 0018:ffff8801d2b16fd8 EFLAGS: 00010293 > >> > RAX: ffff8801d2b08080 RBX: ffff8801d7829300 RCX: ffffffff8403b856 > >> > RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8801d7829330 > >> > RBP: ffff8801d2b17138 R08: ffffffff8403b7d9 R09: 1ffffffff0e53001 > >> > R10: ffff8801d2b16fc8 R11: ffffffff87489d60 R12: 0000000000000000 > >> > R13: dffffc0000000000 R14: ffff8801d2b17110 R15: ffff8801d7829310 > >> > FS: 0000000000000000(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000 > >> > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > >> > CR2: 00000000006d00a8 CR3: 0000000005e25000 CR4: 00000000001406f0 > >> > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > >> > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > >> > Call Trace: > >> > binder_free_proc drivers/android/binder.c:4200 [inline] > >> > binder_proc_dec_tmpref+0x2f3/0x420 drivers/android/binder.c:1833 > >> > binder_deferred_release drivers/android/binder.c:4858 [inline] > >> > binder_deferred_func+0xe22/0x12f0 drivers/android/binder.c:4893 > >> > process_one_work+0xbfd/0x1be0 kernel/workqueue.c:2112 > >> > worker_thread+0x223/0x1990 kernel/workqueue.c:2246 > >> > kthread+0x37a/0x440 kernel/kthread.c:238 > >> > ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:441 > >> > Code: e8 00 40 6c fd 49 8d 7f 20 49 8d 5f f0 48 89 fa 48 c1 ea 03 42 80 3c > >> > 2a 00 0f 85 84 07 00 00 49 83 7f 20 00 74 a9 e8 da 3f 6c fd <0f> 0b 48 8b 9d > >> > e8 fe ff ff 44 89 a5 bc fe ff ff e8 c5 3f 6c fd > >> > RIP: binder_alloc_deferred_release+0x146/0xa40 > >> > drivers/android/binder_alloc.c:750 RSP: ffff8801d2b16fd8 > >> > ---[ end trace 616e085d0dbf3c21 ]--- > >> > Kernel panic - not syncing: Fatal exception > >> > Dumping ftrace buffer: > >> > (ftrace buffer empty) > >> > Kernel Offset: disabled > >> > Rebooting in 86400 seconds.. > >> > >> This crash stopped occurring in v4.15-rc3, and I verified that it was commit > >> fb2c445277e which fixed it (thanks Martijn!). So, telling syzbot so that it can > >> start reporting similar crashes again: > >> > >> #syz fix: ANDROID: binder: fix transaction leak. > > > > Could you change the syz fix format to include the hash in case we want > > to look it up? > > Hi Dan, > > There is an unpleasant issue related to this. Some email clients > (notably gmail) reflow text emails to 72/80 columns and this > transformation is irreversible. So if we add hash, this increases > chances of commit title (what is actually used by syzbot) being > corrupted. > The Reported-by tags allow precise matching of bugs to reports and > back (and that's what I think now is the preferred way to doing the > association as it does not require somebody to go back to the report > email and attach the tag). > Or I can suggest to provide commit hash on a separate line. > The reflow thing is nasty, but hit us periodically. The problem that > should not be there at all, but I don't see a good solution for it. > Obviously requiring developers to follow some formal escaping rules > for titles is not going to work either. Ah, that's fine then, I didn't realize. Eric obviously did include the hash in this email so that's great. regards, dan carpenter