Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754818AbeAMHaE (ORCPT + 1 other); Sat, 13 Jan 2018 02:30:04 -0500 Received: from mail-pl0-f68.google.com ([209.85.160.68]:33192 "EHLO mail-pl0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751163AbeAMHaC (ORCPT ); Sat, 13 Jan 2018 02:30:02 -0500 X-Google-Smtp-Source: ACJfBousy08fYAcS54F4jGPQqXMS7jOF+1l6kCJqK2up+k4Q7c3wfR6xfi+EN368KVidu9J4TmHOLKtqJvihQodhfuw= MIME-Version: 1.0 In-Reply-To: <001a113feecc4fa53a05629c32a5@google.com> References: <001a113feecc4fa53a05629c32a5@google.com> From: Dmitry Vyukov Date: Sat, 13 Jan 2018 08:29:41 +0100 Message-ID: Subject: Re: BUG: unable to handle kernel paging request in check_memory_region To: syzbot Cc: Alexei Starovoitov , Daniel Borkmann , LKML , netdev , syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Fri, Jan 12, 2018 at 11:58 PM, syzbot wrote: > Hello, > > syzkaller hit the following crash on > c92a9a461dff6140c539c61e457aa97df29517d6 > 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 > > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+32b24f3e7c9000c48490@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. Daniel, is it the same bug that was fixed by "bpf, array: fix overflow in max_entries and undefined behavior in index_mask"? > audit: type=1400 audit(1515790631.378:9): avc: denied { sys_chroot } for > pid=3510 comm="syzkaller602893" capability=18 > scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 > tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns > permissive=1 > BUG: unable to handle kernel paging request at ffffed004e875e33 > IP: bytes_is_nonzero mm/kasan/kasan.c:166 [inline] > IP: memory_is_nonzero mm/kasan/kasan.c:184 [inline] > IP: memory_is_poisoned_n mm/kasan/kasan.c:210 [inline] > IP: memory_is_poisoned mm/kasan/kasan.c:241 [inline] > IP: check_memory_region_inline mm/kasan/kasan.c:257 [inline] > IP: check_memory_region+0x61/0x190 mm/kasan/kasan.c:267 > PGD 21ffee067 P4D 21ffee067 PUD 21ffec067 PMD 0 > Oops: 0000 [#1] SMP KASAN > Dumping ftrace buffer: > (ftrace buffer empty) > Modules linked in: > CPU: 0 PID: 3510 Comm: syzkaller602893 Not tainted 4.15.0-rc7+ #259 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:bytes_is_nonzero mm/kasan/kasan.c:166 [inline] > RIP: 0010:memory_is_nonzero mm/kasan/kasan.c:184 [inline] > RIP: 0010:memory_is_poisoned_n mm/kasan/kasan.c:210 [inline] > RIP: 0010:memory_is_poisoned mm/kasan/kasan.c:241 [inline] > RIP: 0010:check_memory_region_inline mm/kasan/kasan.c:257 [inline] > RIP: 0010:check_memory_region+0x61/0x190 mm/kasan/kasan.c:267 > RSP: 0018:ffff8801bfa77770 EFLAGS: 00010202 > RAX: ffffed004e875e33 RBX: ffff8802743af19b RCX: ffffffff817deb1c > RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8802743af198 > RBP: ffff8801bfa77780 R08: 1ffff1004e875e33 R09: ffffed004e875e33 > R10: 0000000000000001 R11: ffffed004e875e33 R12: ffffed004e875e34 > R13: ffff8802743af198 R14: ffff8801bfc9f000 R15: ffff8801c135a680 > FS: 0000000001a1d880(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: ffffed004e875e33 CR3: 00000001bfe22003 CR4: 00000000001606f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > memcpy+0x23/0x50 mm/kasan/kasan.c:302 > memcpy include/linux/string.h:344 [inline] > map_lookup_elem+0x4dc/0xbd0 kernel/bpf/syscall.c:584 > SYSC_bpf kernel/bpf/syscall.c:1711 [inline] > SyS_bpf+0x922/0x4400 kernel/bpf/syscall.c:1685 > entry_SYSCALL_64_fastpath+0x23/0x9a > RIP: 0033:0x440ac9 > RSP: 002b:00000000007dff68 EFLAGS: 00000203 ORIG_RAX: 0000000000000141 > RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000440ac9 > RDX: 0000000000000018 RSI: 0000000020eed000 RDI: 0000000000000001 > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000203 R12: 00000000004022a0 > R13: 0000000000402330 R14: 0000000000000000 R15: 0000000000000000 > Code: 89 f8 49 c1 e8 03 49 89 db 49 c1 eb 03 4d 01 cb 4d 01 c1 4d 8d 63 01 > 4c 89 c8 4d 89 e2 4d 29 ca 49 83 fa 10 7f 3d 4d 85 d2 74 33 <41> 80 39 00 75 > 21 48 b8 01 00 00 00 00 fc ff df 4d 01 d1 49 01 > RIP: bytes_is_nonzero mm/kasan/kasan.c:166 [inline] RSP: ffff8801bfa77770 > RIP: memory_is_nonzero mm/kasan/kasan.c:184 [inline] RSP: ffff8801bfa77770 > RIP: memory_is_poisoned_n mm/kasan/kasan.c:210 [inline] RSP: > ffff8801bfa77770 > RIP: memory_is_poisoned mm/kasan/kasan.c:241 [inline] RSP: ffff8801bfa77770 > RIP: check_memory_region_inline mm/kasan/kasan.c:257 [inline] RSP: > ffff8801bfa77770 > RIP: check_memory_region+0x61/0x190 mm/kasan/kasan.c:267 RSP: > ffff8801bfa77770 > CR2: ffffed004e875e33 > ---[ end trace 769bd3705f3abe78 ]--- > Kernel panic - not syncing: Fatal exception > Dumping ftrace buffer: > (ftrace buffer empty) > Kernel Offset: disabled > Rebooting in 86400 seconds.. > > > --- > 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 > If you want to test a patch for this bug, please reply with: > #syz test: git://repo/address.git branch > and provide the patch inline or as an attachment. > 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/001a113feecc4fa53a05629c32a5%40google.com. > For more options, visit https://groups.google.com/d/optout.