syzbot


KASAN: slab-out-of-bounds Read in hci_le_meta_evt
Status: fixed on 2020/12/30 13:33
Reported-by: syzbot+46682331b57dc6fd00d4@syzkaller.appspotmail.com
Fix commit: 7ee2cd49f722 Bluetooth: Fix slab-out-of-bounds read in hci_le_direct_adv_report_evt()
First crash: 660d, last: 540d

Fix bisection: fixed by (bisect log) :
commit 7ee2cd49f7220b1069e23a65d3ab59526bda9821
Author: Peilin Ye <yepeilin.cs@gmail.com>
Date: Wed Sep 9 07:17:00 2020 +0000

  Bluetooth: Fix slab-out-of-bounds read in hci_le_direct_adv_report_evt()

similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-out-of-bounds Read in hci_le_meta_evt (2) C inconclusive 2 205d 204d 22/22 fixed on 2022/03/08 16:11
linux-4.19 KASAN: slab-out-of-bounds Read in hci_le_meta_evt C done 12 521d 662d 1/1 fixed on 2021/01/18 14:01
linux-4.19 KASAN: slab-out-of-bounds Read in hci_le_meta_evt (2) C error 1 224d 374d 0/1 upstream: reported C repro on 2021/05/14 20:19
upstream KASAN: slab-out-of-bounds Read in hci_le_meta_evt C error error 45 538d 659d 21/22 fixed on 2021/03/10 01:49

Sample crash report:
Bluetooth: Unknown advertising packet type: 0x88
Bluetooth: Unknown advertising packet type: 0x88
Bluetooth: Unknown advertising packet type: 0xff
Bluetooth: Unknown advertising packet type: 0xff
==================================================================
BUG: KASAN: slab-out-of-bounds in hci_le_direct_adv_report_evt net/bluetooth/hci_event.c:5152 [inline]
BUG: KASAN: slab-out-of-bounds in hci_le_meta_evt+0x37d5/0x3fc0 net/bluetooth/hci_event.c:5192
Read of size 1 at addr ffff88809bafe54c by task kworker/u5:1/6368

CPU: 1 PID: 6368 Comm: kworker/u5:1 Not tainted 4.14.195-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: hci0 hci_rx_work
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load1_noabort+0x68/0x70 mm/kasan/report.c:427
 hci_le_direct_adv_report_evt net/bluetooth/hci_event.c:5152 [inline]
 hci_le_meta_evt+0x37d5/0x3fc0 net/bluetooth/hci_event.c:5192
 hci_event_packet+0x19eb/0x7d1d net/bluetooth/hci_event.c:5423
 hci_rx_work+0x3e6/0x970 net/bluetooth/hci_core.c:4244
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

Allocated by task 6365:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551
 __do_kmalloc_node mm/slab.c:3682 [inline]
 __kmalloc_node_track_caller+0x4c/0x70 mm/slab.c:3696
 __kmalloc_reserve net/core/skbuff.c:137 [inline]
 __alloc_skb+0x96/0x510 net/core/skbuff.c:205
 alloc_skb include/linux/skbuff.h:980 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:336 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:180 [inline]
 vhci_write+0xb1/0x420 drivers/bluetooth/hci_vhci.c:299
 call_write_iter include/linux/fs.h:1778 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x44c/0x630 fs/read_write.c:482
 vfs_write+0x17f/0x4d0 fs/read_write.c:544
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

Freed by task 4428:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kfree+0xc9/0x250 mm/slab.c:3815
 kernfs_fop_release+0x10e/0x180 fs/kernfs/file.c:783
 __fput+0x25f/0x7a0 fs/file_table.c:210
 task_work_run+0x11f/0x190 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

The buggy address belongs to the object at ffff88809bafe340
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 12 bytes to the right of
 512-byte region [ffff88809bafe340, ffff88809bafe540)
The buggy address belongs to the page:
page:ffffea00026ebf80 count:1 mapcount:0 mapping:ffff88809bafe0c0 index:0x0
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffff88809bafe0c0 0000000000000000 0000000100000006
raw: ffffea000278f760 ffffea0002792260 ffff88812fe52940 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809bafe400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88809bafe480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88809bafe500: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
                                              ^
 ffff88809bafe580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff88809bafe600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (15):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2020/08/27 03:13 linux-4.14.y d7e78d08fa77 318430cb .config log report syz C
ci2-linux-4-14 2020/08/04 02:51 linux-4.14.y 7f2c5eb458b8 96dd3623 .config log report syz C
ci2-linux-4-14 2020/08/02 12:31 linux-4.14.y 7f2c5eb458b8 96dd3623 .config log report syz C
ci2-linux-4-14 2020/11/30 02:41 linux-4.14.y 87335852c5d9 a0092f9d .config log report info
ci2-linux-4-14 2020/11/20 02:54 linux-4.14.y 8961076ed318 0767f13f .config log report info
ci2-linux-4-14 2020/11/12 19:29 linux-4.14.y 27ce4f2a6817 77a55c8e .config log report info
ci2-linux-4-14 2020/11/09 15:01 linux-4.14.y 6b6446efedb2 cba33199 .config log report info
ci2-linux-4-14 2020/08/29 09:07 linux-4.14.y d7e78d08fa77 d5a3ae1f .config log report
ci2-linux-4-14 2020/08/08 03:11 linux-4.14.y 14b58326976d ff51e522 .config log report
ci2-linux-4-14 2020/08/08 03:11 linux-4.14.y 14b58326976d ff51e522 .config log report
ci2-linux-4-14 2020/08/07 16:18 linux-4.14.y 14b58326976d 28ac5c9e .config log report
ci2-linux-4-14 2020/08/07 15:08 linux-4.14.y 14b58326976d 28ac5c9e .config log report
ci2-linux-4-14 2020/08/02 12:33 linux-4.14.y 7f2c5eb458b8 96dd3623 .config log report
ci2-linux-4-14 2020/08/02 12:32 linux-4.14.y 7f2c5eb458b8 96dd3623 .config log report
ci2-linux-4-14 2020/08/02 12:18 linux-4.14.y 7f2c5eb458b8 96dd3623 .config log report