syzbot


KASAN: use-after-free Read in rfcomm_dlc_exists

Status: auto-closed as invalid on 2020/06/27 18:46
Subsystems: bluetooth
[Documentation on labels]
Reported-by: syzbot+728bead095cef3335bb6@syzkaller.appspotmail.com
First crash: 2092d, last: 1477d
Discussions (4)
Title Replies (including bot) Last reply
Reminder: 29 open syzbot bugs in bluetooth subsystem 1 (1) 2019/07/24 01:41
Reminder: 29 open syzbot bugs in bluetooth subsystem 1 (1) 2019/07/09 19:07
Reminder: 27 open syzbot bugs in bluetooth subsystem 1 (1) 2019/06/24 05:14
KASAN: use-after-free Read in rfcomm_dlc_exists 0 (1) 2018/07/24 07:27
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 KASAN: use-after-free Read in rfcomm_dlc_exists 17 1553d 1758d 0/1 auto-closed as invalid on 2020/05/12 12:00
linux-4.19 KASAN: use-after-free Read in rfcomm_dlc_exists 46 1522d 1763d 0/1 auto-closed as invalid on 2020/06/13 06:12

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in rfcomm_dlc_get net/bluetooth/rfcomm/core.c:360 [inline]
BUG: KASAN: use-after-free in rfcomm_dlc_exists+0x16f/0x190 net/bluetooth/rfcomm/core.c:550
Read of size 1 at addr ffff8880a2549144 by task syz-executor.1/1469

CPU: 0 PID: 1469 Comm: syz-executor.1 Not tainted 5.6.0-rc7-syzkaller #0
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+0x188/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x315 mm/kasan/report.c:374
 __kasan_report.cold+0x1a/0x32 mm/kasan/report.c:506
 kasan_report+0xe/0x20 mm/kasan/common.c:641
 rfcomm_dlc_get net/bluetooth/rfcomm/core.c:360 [inline]
 rfcomm_dlc_exists+0x16f/0x190 net/bluetooth/rfcomm/core.c:550
 __rfcomm_create_dev net/bluetooth/rfcomm/tty.c:413 [inline]
 rfcomm_create_dev net/bluetooth/rfcomm/tty.c:486 [inline]
 rfcomm_dev_ioctl+0x9ea/0x1d70 net/bluetooth/rfcomm/tty.c:588
 rfcomm_sock_ioctl+0x86/0xb0 net/bluetooth/rfcomm/sock.c:902
 sock_do_ioctl+0xd8/0x2f0 net/socket.c:1053
 sock_ioctl+0x3ed/0x790 net/socket.c:1204
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:770
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c849
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f54e62cfc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f54e62d06d4 RCX: 000000000045c849
RDX: 0000000020000100 RSI: 00000000400452c8 RDI: 0000000000000004
RBP: 000000000076bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000316 R14: 00000000004c57dd R15: 000000000076bfac

Allocated by task 18007:
 save_stack+0x1b/0x80 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:515 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:488
 kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551
 kmalloc include/linux/slab.h:555 [inline]
 kzalloc include/linux/slab.h:669 [inline]
 rfcomm_dlc_alloc+0x7a/0x400 net/bluetooth/rfcomm/core.c:305
 rfcomm_sock_alloc.constprop.0+0xad/0x370 net/bluetooth/rfcomm/sock.c:286
 rfcomm_sock_create+0xe0/0x2a0 net/bluetooth/rfcomm/sock.c:329
 bt_sock_create+0x154/0x2a0 net/bluetooth/af_bluetooth.c:130
 __sock_create+0x3cb/0x730 net/socket.c:1433
 sock_create net/socket.c:1484 [inline]
 __sys_socket+0xef/0x200 net/socket.c:1526
 __do_sys_socket net/socket.c:1535 [inline]
 __se_sys_socket net/socket.c:1533 [inline]
 __x64_sys_socket+0x6f/0xb0 net/socket.c:1533
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 1466:
 save_stack+0x1b/0x80 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 kasan_set_free_info mm/kasan/common.c:337 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:476
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 rfcomm_dlc_put include/net/bluetooth/rfcomm.h:258 [inline]
 __rfcomm_create_dev net/bluetooth/rfcomm/tty.c:417 [inline]
 rfcomm_create_dev net/bluetooth/rfcomm/tty.c:486 [inline]
 rfcomm_dev_ioctl+0x1a8c/0x1d70 net/bluetooth/rfcomm/tty.c:588
 rfcomm_sock_ioctl+0x86/0xb0 net/bluetooth/rfcomm/sock.c:902
 sock_do_ioctl+0xd8/0x2f0 net/socket.c:1053
 sock_ioctl+0x3ed/0x790 net/socket.c:1204
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:770
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880a2549000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 324 bytes inside of
 512-byte region [ffff8880a2549000, ffff8880a2549200)
The buggy address belongs to the page:
page:ffffea0002895240 refcount:1 mapcount:0 mapping:ffff8880aa000a80 index:0x0
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea0002a10908 ffffea0002502d88 ffff8880aa000a80
raw: 0000000000000000 ffff8880a2549000 0000000100000004 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a2549000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a2549080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880a2549100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff8880a2549180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a2549200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (833):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/03/29 18:45 upstream e595dd94515e 05736b29 .config console log report ci-upstream-kasan-gce-root
2020/03/23 01:23 upstream 67d584e33e54 78267cec .config console log report ci-upstream-kasan-gce-smack-root
2020/03/18 12:13 upstream ac309e7744be 97bc55ce .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/27 13:05 upstream f8788d86ab28 59b57593 .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/20 09:03 upstream ca7e1fd1026c 81230308 .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/17 04:57 upstream 11a48a5a18c6 1f448cd6 .config console log report ci-upstream-kasan-gce-smack-root
2020/01/18 00:34 upstream ab7541c3addd 3de7aabb .config console log report ci-upstream-kasan-gce-selinux-root
2020/01/15 09:46 upstream 95e20af9fb9c fa12bd3c .config console log report ci-upstream-kasan-gce-smack-root
2020/01/11 05:44 upstream e69ec487b2c7 4de4e9f0 .config console log report ci-upstream-kasan-gce-root
2020/01/15 16:09 upstream 95e20af9fb9c 069a5a44 .config console log report ci-qemu-upstream-386
2020/02/15 16:25 net-old 2019fc96af22 5d7b90f1 .config console log report ci-upstream-net-this-kasan-gce
2020/02/13 21:17 net-old b9287f2ac321 c5ed587f .config console log report ci-upstream-net-this-kasan-gce
2020/02/01 01:37 net-old 9f68e3655aae c30117b2 .config console log report ci-upstream-net-this-kasan-gce
2020/01/17 02:51 net-old 567110f147b3 3de7aabb .config console log report ci-upstream-net-this-kasan-gce
2020/01/17 02:08 net-old 567110f147b3 3de7aabb .config console log report ci-upstream-net-this-kasan-gce
2020/01/17 00:32 net-old 567110f147b3 3de7aabb .config console log report ci-upstream-net-this-kasan-gce
2020/01/16 12:37 net-old 567110f147b3 3de7aabb .config console log report ci-upstream-net-this-kasan-gce
2020/01/15 18:12 net-old 8b792f84c637 f9b69507 .config console log report ci-upstream-net-this-kasan-gce
2020/01/15 11:59 net-old 8c4df83fbe60 fa12bd3c .config console log report ci-upstream-net-this-kasan-gce
2020/01/15 08:01 net-old f8d7408a4d7f fa12bd3c .config console log report ci-upstream-net-this-kasan-gce
2020/01/15 05:22 net-old f8d7408a4d7f fa12bd3c .config console log report ci-upstream-net-this-kasan-gce
2020/01/15 03:37 net-old f8d7408a4d7f fa12bd3c .config console log report ci-upstream-net-this-kasan-gce
2020/01/15 02:17 net-old f8d7408a4d7f fa12bd3c .config console log report ci-upstream-net-this-kasan-gce
2020/01/15 01:03 net-old f8d7408a4d7f fa12bd3c .config console log report ci-upstream-net-this-kasan-gce
2020/01/14 23:12 net-old f8d7408a4d7f fa12bd3c .config console log report ci-upstream-net-this-kasan-gce
2020/01/14 19:56 net-old f8d7408a4d7f fa12bd3c .config console log report ci-upstream-net-this-kasan-gce
2020/01/14 18:39 net-old a112adafcb47 32881205 .config console log report ci-upstream-net-this-kasan-gce
2020/01/14 16:06 net-old a112adafcb47 32881205 .config console log report ci-upstream-net-this-kasan-gce
2020/01/14 12:33 net-old a112adafcb47 32881205 .config console log report ci-upstream-net-this-kasan-gce
2020/01/14 10:28 net-old a112adafcb47 32881205 .config console log report ci-upstream-net-this-kasan-gce
2020/01/14 04:06 net-old a112adafcb47 32881205 .config console log report ci-upstream-net-this-kasan-gce
2020/01/13 19:14 net-old c9f53049d4a8 99565c1a .config console log report ci-upstream-net-this-kasan-gce
2020/01/13 11:29 net-old c9f53049d4a8 99565c1a .config console log report ci-upstream-net-this-kasan-gce
2020/01/12 23:21 net-old c9f53049d4a8 53faa9fe .config console log report ci-upstream-net-this-kasan-gce
2020/01/12 16:10 net-old c9f53049d4a8 31290a45 .config console log report ci-upstream-net-this-kasan-gce
2020/01/12 11:41 net-old c9f53049d4a8 31290a45 .config console log report ci-upstream-net-this-kasan-gce
2020/01/12 07:54 net-old c9f53049d4a8 4c04afaa .config console log report ci-upstream-net-this-kasan-gce
2020/01/12 03:17 net-old a5c3a7c0ce1a 4c04afaa .config console log report ci-upstream-net-this-kasan-gce
2020/01/11 23:19 net-old a5c3a7c0ce1a 4c04afaa .config console log report ci-upstream-net-this-kasan-gce
2020/01/11 21:39 net-old a5c3a7c0ce1a 4c04afaa .config console log report ci-upstream-net-this-kasan-gce
2020/01/11 18:26 net-old a5c3a7c0ce1a 4c04afaa .config console log report ci-upstream-net-this-kasan-gce
2020/01/11 06:00 net-old e267371dd376 4de4e9f0 .config console log report ci-upstream-net-this-kasan-gce
2020/01/10 21:01 net-old e267371dd376 4de4e9f0 .config console log report ci-upstream-net-this-kasan-gce
2020/03/14 18:51 net-next-old 94229d45239b 749688d2 .config console log report ci-upstream-net-kasan-gce
2020/01/29 19:05 net-next-old b3a608222336 5ed23f9a .config console log report ci-upstream-net-kasan-gce
2020/01/16 22:00 net-next-old 1ccf6c13d9c7 3de7aabb .config console log report ci-upstream-net-kasan-gce
2020/01/13 23:53 net-next-old e07c5f2e4e91 99565c1a .config console log report ci-upstream-net-kasan-gce
2020/01/07 11:12 net-next-old 1b935183aeff 1bcd407e .config console log report ci-upstream-net-kasan-gce
2019/11/21 05:00 linux-next 1fef9976397f 8098ea0f .config console log report ci-upstream-linux-next-kasan-gce-root
2018/07/23 20:30 linux-next 89cf55353308 912c93d7 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.