syzbot


KASAN: use-after-free Read in h5_reset_rx

Status: fixed on 2019/03/28 12:00
Subsystems: bluetooth
[Documentation on labels]
Reported-by: syzbot+899a33dc0fa0dbaf06a6@syzkaller.appspotmail.com
Fix commit: 56897b217a1d Bluetooth: hci_ldisc: Postpone HCI_UART_PROTO_READY bit set in hci_uart_set_proto()
First crash: 1944d, last: 1936d
Discussions (8)
Title Replies (including bot) Last reply
[PATCH 4.4 000/159] 4.4.203-stable review 179 (179) 2019/11/28 10:35
[PATCH 3.16 000/132] 3.16.74-rc1 review 141 (141) 2019/11/19 20:40
[PATCH 4.9 00/31] 4.9.202-stable review 43 (43) 2019/11/19 04:47
[PATCH 5.0 00/52] 5.0.5-stable review 61 (61) 2019/03/27 05:06
[PATCH 4.19 00/45] 4.19.32-stable review 51 (51) 2019/03/27 04:04
[PATCH 4.14 00/41] 4.14.109-stable review 47 (47) 2019/03/26 23:15
[PATCH] Bluetooth: hci_ldisc: Postpone HCI_UART_PROTO_READY bit set in hci_uart_set_proto() 3 (3) 2019/02/26 08:56
KASAN: use-after-free Read in h5_reset_rx 0 (1) 2019/02/20 06:45

Sample crash report:
kasan: CONFIG_KASAN_INLINE enabled
Bluetooth: Can't allocate HCI device
Bluetooth: Invalid header checksum
netlink: 'syz-executor.4': attribute type 1 has an invalid length.
==================================================================
BUG: KASAN: use-after-free in h5_reset_rx+0xe0/0x100 drivers/bluetooth/hci_h5.c:544
Read of size 8 at addr ffff88803c3bcbd8 by task kworker/u4:0/18103

CPU: 0 PID: 18103 Comm: kworker/u4:0 Not tainted 5.0.0-rc8 #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound flush_to_ldisc
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 h5_reset_rx+0xe0/0x100 drivers/bluetooth/hci_h5.c:544
 h5_rx_3wire_hdr+0x2f5/0x3c0 drivers/bluetooth/hci_h5.c:455
 h5_recv+0x30a/0x4c0 drivers/bluetooth/hci_h5.c:578
netlink: 'syz-executor.2': attribute type 1 has an invalid length.
 hci_uart_tty_receive+0x22b/0x530 drivers/bluetooth/hci_ldisc.c:607
 tty_ldisc_receive_buf+0x164/0x1c0 drivers/tty/tty_buffer.c:465
 tty_port_default_receive_buf+0x7d/0xb0 drivers/tty/tty_port.c:38
 receive_buf drivers/tty/tty_buffer.c:481 [inline]
 flush_to_ldisc+0x228/0x390 drivers/tty/tty_buffer.c:533
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2173
 worker_thread+0x98/0xe40 kernel/workqueue.c:2319
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Allocated by task 23376:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:495 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:468
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:509
 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3615
 kmalloc include/linux/slab.h:545 [inline]
 kzalloc include/linux/slab.h:740 [inline]
 h5_open+0x4e4/0x5f0 drivers/bluetooth/hci_h5.c:222
 hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:686 [inline]
 hci_uart_tty_ioctl+0x2d4/0xa70 drivers/bluetooth/hci_ldisc.c:748
 tty_ioctl+0xac9/0x14d0 drivers/tty/tty_io.c:2662
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
 ksys_ioctl+0xab/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+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 23376:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:457
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:465
 __cache_free mm/slab.c:3494 [inline]
 kfree+0xcf/0x230 mm/slab.c:3811
 h5_close+0x11a/0x150 drivers/bluetooth/hci_h5.c:266
 hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:696 [inline]
 hci_uart_tty_ioctl+0x839/0xa70 drivers/bluetooth/hci_ldisc.c:748
 tty_ioctl+0xac9/0x14d0 drivers/tty/tty_io.c:2662
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
 ksys_ioctl+0xab/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+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88803c3bc900
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 728 bytes inside of
 1024-byte region [ffff88803c3bc900, ffff88803c3bcd00)
The buggy address belongs to the page:
page:ffffea0000f0ef00 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea0002245b08 ffff88812c3f1848 ffff88812c3f0ac0
raw: 0000000000000000 ffff88803c3bc000 0000000100000007 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88803c3bca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803c3bcb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88803c3bcb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff88803c3bcc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803c3bcc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
netlink: 'syz-executor.4': attribute type 1 has an invalid length.
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 10751 Comm: kworker/0:4 Tainted: G    B             5.0.0-rc8 #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events hci_uart_write_work
RIP: 0010:hci_uart_write_work+0x1b6/0x710 drivers/bluetooth/hci_ldisc.c:180
Code: 0f 85 6a 04 00 00 49 8b b4 24 c8 00 00 00 4c 89 ef e8 de 57 53 02 89 c6 48 8b 45 d0 48 8d b8 5c 10 00 00 48 89 f8 48 c1 e8 03 <0f> b6 14 18 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 1d
RSP: 0018:ffff88809127fcb0 EFLAGS: 00010203
RAX: 000000000000020b RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000000000000105c
RBP: ffff88809127fd30 R08: ffff8880a8700440 R09: ffff8880a8700d08
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888081578080
R13: ffff8880a8f2edc0 R14: ffff88809a4bd0e8 R15: ffff8880815780f0
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2195a42db8 CR3: 000000005492b000 CR4: 00000000001426f0
Call Trace:
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2173
 worker_thread+0x98/0xe40 kernel/workqueue.c:2319
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Modules linked in:
---[ end trace c10edbba2a1e3d1f ]---
RIP: 0010:hci_uart_write_work+0x1b6/0x710 drivers/bluetooth/hci_ldisc.c:180
Code: 0f 85 6a 04 00 00 49 8b b4 24 c8 00 00 00 4c 89 ef e8 de 57 53 02 89 c6 48 8b 45 d0 48 8d b8 5c 10 00 00 48 89 f8 48 c1 e8 03 <0f> b6 14 18 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 1d
Dev loop3: unable to read RDB block 1
kobject: 'loop2' (000000006693825d): kobject_uevent_env
kobject: 'loop2' (000000006693825d): fill_kobj_path: path = '/devices/virtual/block/loop2'
 loop3: unable to read partition table
loop3: partition table beyond EOD, truncated
kobject: 'loop5' (0000000019bd2c4b): kobject_uevent_env
RSP: 0018:ffff88809127fcb0 EFLAGS: 00010203
loop_reread_partitions: partition scan of loop3 () failed (rc=-5)
RAX: 000000000000020b RBX: dffffc0000000000 RCX: 0000000000000000
kobject: 'loop5' (0000000019bd2c4b): fill_kobj_path: path = '/devices/virtual/block/loop5'
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 000000000000105c
RBP: ffff88809127fd30 R08: ffff8880a8700440 R09: ffff8880a8700d08
kobject: 'loop4' (000000008602ee67): kobject_uevent_env
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888081578080
kobject: 'loop4' (000000008602ee67): fill_kobj_path: path = '/devices/virtual/block/loop4'
R13: ffff8880a8f2edc0 R14: ffff88809a4bd0e8 R15: ffff8880815780f0
kobject: 'loop4' (000000008602ee67): kobject_uevent_env
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
kobject: 'loop4' (000000008602ee67): fill_kobj_path: path = '/devices/virtual/block/loop4'
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd0511017d8 CR3: 000000005492b000 CR4: 00000000001426f0

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/02/25 16:13 upstream 5908e6b738e3 a70141bf .config console log report ci-upstream-kasan-gce-smack-root
2019/02/17 23:39 linux-next 7a92eb7cc1dc 3e98cc30 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.