From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933607AbeD0PSc (ORCPT ); Fri, 27 Apr 2018 11:18:32 -0400 Received: from mail-pf0-f173.google.com ([209.85.192.173]:44316 "EHLO mail-pf0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932845AbeD0PS2 (ORCPT ); Fri, 27 Apr 2018 11:18:28 -0400 X-Google-Smtp-Source: AB8JxZqyDU5Y5/e2r2kzR6QpPrkf01nHu1RbuOPg2bGMUc6WgEMg5+0S8JzhkcsumMfCa2UmvaGwWbRKKFbiLmJySKw= MIME-Version: 1.0 In-Reply-To: <000000000000c1d8f1056acdcbfa@google.com> References: <000000000000c1d8f1056acdcbfa@google.com> From: Dmitry Vyukov Date: Fri, 27 Apr 2018 17:18:06 +0200 Message-ID: Subject: Re: BUG: unable to handle kernel paging request in process_preds To: syzbot Cc: LKML , Ingo Molnar , Steven Rostedt , syzkaller-bugs Content-Type: text/plain; charset="UTF-8" X-ccpol: medium Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 27, 2018 at 7:30 AM, syzbot wrote: > Hello, > > syzbot hit the following crash on bpf-next commit > 0c90f2243ec67eeacf9624ae52ab43c734fe0e93 (Wed Apr 18 02:46:34 2018 +0000) > tools: bpftool: make it easier to feed hex bytes to bpftool > syzbot dashboard link: > https://syzkaller.appspot.com/bug?extid=b76562b749bb67fca79f > > Unfortunately, I don't have any reproducer for this crash yet. > Raw console output: > https://syzkaller.appspot.com/x/log.txt?id=5319914659250176 > Kernel config: > https://syzkaller.appspot.com/x/.config?id=-5947642240294114534 > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+b76562b749bb67fca79f@syzkaller.appspotmail.com > It will help syzbot understand when the bug is fixed. See footer for > details. > If you forward the report, please keep this part and the footer. #syz dup: KASAN: use-after-free Read in process_preds > BUG: unable to handle kernel paging request at ffff87f9dbf70994 > PGD 0 P4D 0 > Oops: 0000 [#1] SMP KASAN > Dumping ftrace buffer: > (ftrace buffer empty) > Modules linked in: > CPU: 1 PID: 7133 Comm: syz-executor4 Not tainted 4.16.0+ #4 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:predicate_parse kernel/trace/trace_events_filter.c:563 [inline] > RIP: 0010:process_preds+0x146c/0x19b0 > kernel/trace/trace_events_filter.c:1505 > RSP: 0018:ffff880197cc7438 EFLAGS: 00010246 > RAX: 0000000000000007 RBX: ffff87f9dbf70990 RCX: 0000000000000000 > RDX: 00000000ffffffff RSI: ffffffff817f1ee9 RDI: ffff87f9dbf70994 > RBP: ffff880197cc7540 R08: ffff8801b2146540 R09: ffffed003b6246c2 > R10: ffffed003b6246c2 R11: ffff8801db123613 R12: dffffc0000000000 > R13: ffff8801c1f04fe0 R14: 00000000fffffffe R15: dffffc0000000000 > FS: 00007fedc5480700(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: ffff87f9dbf70994 CR3: 00000001a0041000 CR4: 00000000001406e0 > DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 > Call Trace: > create_filter+0x1a8/0x370 kernel/trace/trace_events_filter.c:1714 > ftrace_profile_set_filter+0x109/0x2b0 > kernel/trace/trace_events_filter.c:2042 > perf_event_set_filter+0x248/0x1230 kernel/events/core.c:9064 > _perf_ioctl+0x84c/0x15e0 kernel/events/core.c:5056 > perf_ioctl+0x59/0x80 kernel/events/core.c:5107 > vfs_ioctl fs/ioctl.c:46 [inline] > file_ioctl fs/ioctl.c:500 [inline] > do_vfs_ioctl+0x1cf/0x16a0 fs/ioctl.c:684 > ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701 > SYSC_ioctl fs/ioctl.c:708 [inline] > SyS_ioctl+0x24/0x30 fs/ioctl.c:706 > do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287 > entry_SYSCALL_64_after_hwframe+0x42/0xb7 > RIP: 0033:0x455329 > RSP: 002b:00007fedc547fc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 00007fedc54806d4 RCX: 0000000000455329 > RDX: 0000000020000100 RSI: 0000000040082406 RDI: 0000000000000014 > RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff > R13: 0000000000000291 R14: 00000000006f6e38 R15: 0000000000000000 > Code: ff ff 41 8b 55 04 48 8d 7b 04 48 89 f8 48 c1 e8 03 42 0f b6 0c 20 48 > 89 f8 83 e0 07 83 c0 03 38 c8 7c 08 84 c9 0f 85 08 05 00 00 <44> 8b 7b 04 89 > d7 89 95 68 ff ff ff 44 89 fe e8 80 0a f8 ff 8b > RIP: predicate_parse kernel/trace/trace_events_filter.c:563 [inline] RSP: > ffff880197cc7438 > RIP: process_preds+0x146c/0x19b0 kernel/trace/trace_events_filter.c:1505 > RSP: ffff880197cc7438 > CR2: ffff87f9dbf70994 > ---[ end trace 9971f5aefc423124 ]--- > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkaller@googlegroups.com. > > syzbot will keep track of this bug report. > If you forgot to add the Reported-by tag, once the fix for this bug is > merged > into any tree, please reply to this email with: > #syz fix: exact-commit-title > To mark this as a duplicate of another syzbot report, please reply with: > #syz dup: exact-subject-of-another-report > If it's a one-off invalid bug report, please reply with: > #syz invalid > Note: if the crash happens again, it will cause creation of a new bug > report. > Note: all commands must start from beginning of the line in the email body. > > -- > You received this message because you are subscribed to the Google Groups > "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to syzkaller-bugs+unsubscribe@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/000000000000c1d8f1056acdcbfa%40google.com. > For more options, visit https://groups.google.com/d/optout.