syzbot

 sign-in | mailing list | source | docs
🐞 Open [1506]
≡ Subsystems
🐞 Fixed [5869]
🐞 Invalid [14301]
⬇ Missing Backports [95]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
Total Repo Heatmap Subsystems Heatmap
💬 Send us feedback

KASAN: use-after-free Read in vb2_mmap

Status: fixed on 2019/01/11 01:22
Subsystems: media
[Documentation on labels]
Reported-by: syzbot+be93025dd45dccd8923c@syzkaller.appspotmail.com
Fix commit: cd26d1c4d1bc media: vb2: vb2_mmap: move lock up
First crash: 2225d, last: 2169d
▶ ▼ Discussions (9)
Title Replies (including bot) Last reply
[PATCH 4.19 00/99] 4.19.17-stable review 109 (109) 2019/04/22 19:40
[PATCH 4.4 000/104] 4.4.172-stable review 111 (111) 2019/01/30 07:30
[PATCH 3.18 00/52] 3.18.133-stable review 55 (55) 2019/01/25 23:16
[PATCH 4.14 00/59] 4.14.95-stable review 65 (65) 2019/01/23 12:55
[PATCH 4.9 00/51] 4.9.152-stable review 56 (56) 2019/01/23 09:06
[PATCH 4.20 000/111] 4.20.4-stable review 120 (120) 2019/01/23 06:43
[PATCH] media: videobuf2-core: fix use after free in vb2_mmap 2 (2) 2018/11/17 09:00
[PATCH] vb2: vb2_mmap: move lock up 1 (1) 2018/11/13 14:06
KASAN: use-after-free Read in vb2_mmap 0 (1) 2018/10/30 10:48

Sample crash report:
sshd (6044) used greatest stack depth: 15744 bytes left
==================================================================
BUG: KASAN: use-after-free in vb2_mmap+0x662/0x6f0 drivers/media/common/videobuf2/videobuf2-core.c:2147
Read of size 8 at addr ffff8881ccc42d80 by task syz-executor444/6068

CPU: 0 PID: 6068 Comm: syz-executor444 Not tainted 4.20.0-rc4+ #353
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x244/0x39d lib/dump_stack.c:113
 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 vb2_mmap+0x662/0x6f0 drivers/media/common/videobuf2/videobuf2-core.c:2147
 vb2_fop_mmap+0x4b/0x70 drivers/media/common/videobuf2/videobuf2-v4l2.c:999
 v4l2_mmap+0x153/0x200 drivers/media/v4l2-core/v4l2-dev.c:401
 call_mmap include/linux/fs.h:1862 [inline]
 mmap_region+0xe85/0x1cd0 mm/mmap.c:1786
 do_mmap+0xa22/0x1230 mm/mmap.c:1559
 do_mmap_pgoff include/linux/mm.h:2328 [inline]
 vm_mmap_pgoff+0x213/0x2c0 mm/util.c:350
 ksys_mmap_pgoff+0x4da/0x660 mm/mmap.c:1609
 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:100 [inline]
 __se_sys_mmap arch/x86/kernel/sys_x86_64.c:91 [inline]
 __x64_sys_mmap+0xe9/0x1b0 arch/x86/kernel/sys_x86_64.c:91
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x444c89
Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 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 0f 83 2b ce fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc42fec548 EFLAGS: 00000212 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444c89
RDX: fffffffffffffffd RSI: 0000000000002000 RDI: 0000000020ffe000
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000212 R12: 0000000000401f40
R13: 0000000000401fd0 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 6063:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
 __do_kmalloc mm/slab.c:3722 [inline]
 __kmalloc+0x15b/0x760 mm/slab.c:3731
 kmalloc include/linux/slab.h:551 [inline]
 kzalloc include/linux/slab.h:741 [inline]
 __vb2_queue_alloc+0xf7/0xf90 drivers/media/common/videobuf2/videobuf2-core.c:343
 vb2_core_create_bufs+0x401/0x8c0 drivers/media/common/videobuf2/videobuf2-core.c:834
 vb2_create_bufs+0x3c6/0x7f0 drivers/media/common/videobuf2/videobuf2-v4l2.c:716
 vb2_ioctl_create_bufs+0x25e/0x3d0 drivers/media/common/videobuf2/videobuf2-v4l2.c:916
 v4l_create_bufs+0x152/0x230 drivers/media/v4l2-core/v4l2-ioctl.c:1927
 __video_do_ioctl+0x8b1/0x1050 drivers/media/v4l2-core/v4l2-ioctl.c:2853
 video_usercopy+0x5c1/0x1760 drivers/media/v4l2-core/v4l2-ioctl.c:3035
 video_ioctl2+0x2c/0x33 drivers/media/v4l2-core/v4l2-ioctl.c:3079
 v4l2_ioctl+0x154/0x1b0 drivers/media/v4l2-core/v4l2-dev.c:364
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 6063:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xcf/0x230 mm/slab.c:3817
 __vb2_queue_free+0x5e2/0xa30 drivers/media/common/videobuf2/videobuf2-core.c:526
 vb2_core_queue_release+0x62/0x80 drivers/media/common/videobuf2/videobuf2-core.c:2231
 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:837 [inline]
 _vb2_fop_release+0x1d2/0x2b0 drivers/media/common/videobuf2/videobuf2-v4l2.c:1010
 vb2_fop_release+0x77/0xc0 drivers/media/common/videobuf2/videobuf2-v4l2.c:1024
 vivid_fop_release+0x18e/0x440 drivers/media/platform/vivid/vivid-core.c:474
 v4l2_release+0x224/0x3a0 drivers/media/v4l2-core/v4l2-dev.c:456
 __fput+0x385/0xa30 fs/file_table.c:278
 ____fput+0x15/0x20 fs/file_table.c:309
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x1ad6/0x26d0 kernel/exit.c:867
 do_group_exit+0x177/0x440 kernel/exit.c:970
 __do_sys_exit_group kernel/exit.c:981 [inline]
 __se_sys_exit_group kernel/exit.c:979 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:979
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881ccc42d80
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 0 bytes inside of
 1024-byte region [ffff8881ccc42d80, ffff8881ccc43180)
The buggy address belongs to the page:
page:ffffea0007331080 count:1 mapcount:0 mapping:ffff8881da800ac0 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000010200(slab|head)
raw: 02fffc0000010200 ffffea0007347288 ffffea0007332988 ffff8881da800ac0
raw: 0000000000000000 ffff8881ccc42000 0000000100000007 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881ccc42c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881ccc42d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881ccc42d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8881ccc42e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881ccc42e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (276):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/11/29 04:23 upstream 121b018f8c74 4b6d14f2 .config console log report syz C ci-upstream-kasan-gce
2018/11/29 04:22 upstream 121b018f8c74 4b6d14f2 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2018/11/29 04:21 upstream 121b018f8c74 4b6d14f2 .config console log report syz C ci-upstream-kasan-gce-root
2018/11/29 03:47 upstream 121b018f8c74 4b6d14f2 .config console log report syz C ci-upstream-kasan-gce-smack-root
2018/11/12 00:05 upstream e255aee5b66c 7b5f8621 .config console log report syz C ci-upstream-kasan-gce
2018/11/11 02:49 upstream ab6e1f378f54 f3c4e618 .config console log report syz C ci-upstream-kasan-gce-root
2018/11/11 02:37 upstream ab6e1f378f54 f3c4e618 .config console log report syz C ci-upstream-kasan-gce-smack-root
2018/11/11 02:34 upstream ab6e1f378f54 f3c4e618 .config console log report syz C ci-upstream-kasan-gce
2018/11/11 01:30 upstream ab6e1f378f54 f3c4e618 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2018/11/06 15:55 upstream 163c8d54a997 8bd6bd63 .config console log report syz C ci-upstream-kasan-gce-smack-root
2018/11/06 15:30 upstream 163c8d54a997 8bd6bd63 .config console log report syz C ci-upstream-kasan-gce-smack-root
2018/11/06 02:49 upstream 163c8d54a997 8bd6bd63 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2018/11/05 03:17 upstream 4710e78940d8 8bd6bd63 .config console log report syz C ci-upstream-kasan-gce-root
2018/11/05 02:54 upstream 4710e78940d8 8bd6bd63 .config console log report syz C ci-upstream-kasan-gce-root
2018/11/04 07:21 upstream d2ff0ff2c23f 8bd6bd63 .config console log report syz C ci-upstream-kasan-gce
2018/11/04 06:56 upstream d2ff0ff2c23f 8bd6bd63 .config console log report syz C ci-upstream-kasan-gce
2018/10/30 18:52 upstream 11743c56785c 8dbb755a .config console log report syz C ci-upstream-kasan-gce-smack-root
2018/10/30 18:10 upstream 11743c56785c 8dbb755a .config console log report syz C ci-upstream-kasan-gce-smack-root
2018/10/30 17:26 upstream 11743c56785c 8dbb755a .config console log report syz C ci-upstream-kasan-gce-selinux-root
2018/10/30 16:26 upstream 11743c56785c 8dbb755a .config console log report syz C ci-upstream-kasan-gce-selinux-root
2018/10/30 15:44 upstream 11743c56785c 8dbb755a .config console log report syz C ci-upstream-kasan-gce-selinux-root
2018/10/30 15:00 upstream 11743c56785c 8dbb755a .config console log report syz C ci-upstream-kasan-gce-root
2018/10/30 14:58 upstream 11743c56785c 8dbb755a .config console log report syz C ci-upstream-kasan-gce
2018/10/30 11:52 upstream 4b42745211af 2f1090da .config console log report syz C ci-upstream-kasan-gce
2018/10/30 11:33 upstream 4b42745211af 2f1090da .config console log report syz C ci-upstream-kasan-gce-root
2018/10/30 11:24 upstream 4b42745211af 2f1090da .config console log report syz C ci-upstream-kasan-gce-smack-root
2018/10/30 11:10 upstream 4b42745211af 2f1090da .config console log report syz C ci-upstream-kasan-gce
2018/11/29 04:23 upstream 121b018f8c74 4b6d14f2 .config console log report syz C ci-upstream-kasan-gce-386
2018/11/11 06:35 upstream ab6e1f378f54 f3c4e618 .config console log report syz C ci-upstream-kasan-gce-386
2018/11/04 05:01 upstream 83650fd58a93 8bd6bd63 .config console log report syz C ci-upstream-kasan-gce-386
2018/11/04 04:38 upstream 83650fd58a93 8bd6bd63 .config console log report syz C ci-upstream-kasan-gce-386
2018/10/30 20:50 upstream 11743c56785c 8dbb755a .config console log report syz C ci-upstream-kasan-gce-386
2018/10/30 20:19 upstream 11743c56785c 8dbb755a .config console log report syz C ci-upstream-kasan-gce-386
2018/10/30 10:42 upstream 4b42745211af 2f1090da .config console log report syz C ci-upstream-kasan-gce-386
2018/11/29 12:00 linux-next 442b8cea2477 4b6d14f2 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2018/11/11 07:25 linux-next 442b8cea2477 f3c4e618 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2018/11/06 02:44 linux-next 55e5059cb572 8bd6bd63 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2018/11/06 02:21 linux-next 55e5059cb572 8bd6bd63 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2018/10/30 14:31 linux-next 6201f31a39f8 8dbb755a .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2018/10/30 11:31 linux-next 6201f31a39f8 2f1090da .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2018/12/25 22:50 upstream 8fe28cb58bcb 8a41a0ad .config console log report ci-upstream-kasan-gce
2018/12/25 18:17 upstream 8fe28cb58bcb 8a41a0ad .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/25 06:51 upstream 8fe28cb58bcb 8a41a0ad .config console log report ci-upstream-kasan-gce
2018/12/24 15:25 upstream 8fe28cb58bcb be79df56 .config console log report ci-upstream-kasan-gce-smack-root
2018/12/23 14:45 upstream 9105b8aa50c1 e3bd7ab8 .config console log report ci-upstream-kasan-gce-smack-root
2018/12/23 12:06 upstream 9105b8aa50c1 e3bd7ab8 .config console log report ci-upstream-kasan-gce-smack-root
2018/12/23 02:40 upstream 9105b8aa50c1 e3bd7ab8 .config console log report ci-upstream-kasan-gce-root
2018/12/22 06:18 upstream 5092adb2272e 603b5124 .config console log report ci-upstream-kasan-gce-smack-root
2018/12/21 09:12 upstream 9097a058d49e 2b497001 .config console log report ci-upstream-kasan-gce-smack-root
2018/12/20 22:54 upstream 1d51b4b1d3f2 aaf59e84 .config console log report ci-upstream-kasan-gce-root
2018/12/19 14:43 upstream 62393dbcbe0f fe2dc057 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/18 12:01 upstream 1a9430db2835 4edaba93 .config console log report ci-upstream-kasan-gce
2018/12/18 06:46 upstream 1a9430db2835 def91db3 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/18 01:46 upstream 1a9430db2835 def91db3 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/16 23:52 upstream 6531e115b7ab def91db3 .config console log report ci-upstream-kasan-gce-root
2018/12/16 15:53 upstream 6531e115b7ab def91db3 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/16 12:58 upstream 6531e115b7ab def91db3 .config console log report ci-upstream-kasan-gce
2018/12/16 04:17 upstream 6531e115b7ab def91db3 .config console log report ci-upstream-kasan-gce
2018/12/15 03:04 upstream eb6cf9f8cb9d 7624ddd6 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/14 10:27 upstream 65e08c5e8631 fe7127be .config console log report ci-upstream-kasan-gce
2018/12/13 04:07 upstream f5d582777bcb 02613a41 .config console log report ci-upstream-kasan-gce-root
2018/12/13 00:25 upstream f5d582777bcb 02613a41 .config console log report ci-upstream-kasan-gce
2018/12/12 20:31 upstream f5d582777bcb c3b10a5d .config console log report ci-upstream-kasan-gce-smack-root
2018/12/12 08:10 upstream f5d582777bcb 7795ae03 .config console log report ci-upstream-kasan-gce
2018/12/12 07:03 upstream f5d582777bcb 7795ae03 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/11 14:47 upstream f5d582777bcb 7795ae03 .config console log report ci-upstream-kasan-gce-smack-root
2018/12/11 14:11 upstream f5d582777bcb 7795ae03 .config console log report ci-upstream-kasan-gce
2018/12/11 12:12 upstream f5d582777bcb 7795ae03 .config console log report ci-upstream-kasan-gce
2018/12/11 06:15 upstream f5d582777bcb 4093e33b .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/10 16:56 upstream 40e020c129cf 6565f24d .config console log report ci-upstream-kasan-gce-root
2018/12/10 01:15 upstream 0844895a2e51 96cc4c50 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/09 17:36 upstream 8214bdf7d3e6 979179d6 .config console log report ci-upstream-kasan-gce-smack-root
2018/12/08 01:35 upstream 5f179793f0a7 65ed2472 .config console log report ci-upstream-kasan-gce
2018/12/06 23:46 upstream abb8d6ecbd8f dcf836b1 .config console log report ci-upstream-kasan-gce-smack-root
2018/12/06 11:27 upstream cf76c364a1e1 3ab38479 .config console log report ci-upstream-kasan-gce
2018/12/06 02:00 upstream d08970904582 764b42c4 .config console log report ci-upstream-kasan-gce
2018/12/06 00:42 upstream d08970904582 764b42c4 .config console log report ci-upstream-kasan-gce-root
2018/12/05 13:02 upstream 0072a0c14d5b ac6c0578 .config console log report ci-upstream-kasan-gce
2018/12/05 01:38 upstream 0072a0c14d5b f162ad97 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/04 21:47 upstream 0072a0c14d5b 6ad0ae61 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/04 20:04 upstream 0072a0c14d5b 6ad0ae61 .config console log report ci-upstream-kasan-gce
2018/12/03 19:11 upstream 2595646791c3 819002b0 .config console log report ci-upstream-kasan-gce-selinux-root
2018/10/30 09:42 upstream 4b42745211af 2f1090da .config console log report ci-upstream-kasan-gce-smack-root
2018/12/23 09:36 upstream 9105b8aa50c1 e3bd7ab8 .config console log report ci-upstream-kasan-gce-386
2018/12/20 04:11 upstream ab63e725b49c 02e69052 .config console log report ci-upstream-kasan-gce-386
2018/12/19 08:05 upstream 62393dbcbe0f 4edaba93 .config console log report ci-upstream-kasan-gce-386
2018/12/17 21:44 upstream 7566ec393f41 def91db3 .config console log report ci-upstream-kasan-gce-386
2018/12/17 19:06 upstream 7566ec393f41 def91db3 .config console log report ci-upstream-kasan-gce-386
2018/12/15 04:46 upstream eb6cf9f8cb9d 7624ddd6 .config console log report ci-upstream-kasan-gce-386
2018/12/09 11:09 upstream 8214bdf7d3e6 979179d6 .config console log report ci-upstream-kasan-gce-386
2018/12/02 03:16 linux-next 442b8cea2477 5a581673 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.