syzbot


KASAN: use-after-free Read in hci_ncmd_timeout

Status: upstream: reported on 2024/08/30 00:12
Reported-by: syzbot+1fb96bdc751886f5f860@syzkaller.appspotmail.com
First crash: 53d, last: 53d

Sample crash report:
Bluetooth: hci2: Controller not accepting commands anymore: ncmd = 0
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: use-after-free in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
BUG: KASAN: use-after-free in hci_ncmd_timeout+0x7c/0x200 net/bluetooth/hci_core.c:2802
Read of size 8 at addr ffff888015bf40a8 by task kworker/0:4/3617

CPU: 0 PID: 3617 Comm: kworker/0:4 Not tainted 5.15.165-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: events hci_ncmd_timeout
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 kasan_check_range+0x27e/0x290 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 hci_ncmd_timeout+0x7c/0x200 net/bluetooth/hci_core.c:2802
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Allocated by task 3570:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513
 kasan_kmalloc include/linux/kasan.h:264 [inline]
 __kmalloc+0x168/0x300 mm/slub.c:4407
 kmalloc include/linux/slab.h:596 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 hci_alloc_dev_priv+0x23/0x1d60 net/bluetooth/hci_core.c:3775
 hci_alloc_dev include/net/bluetooth/hci_core.h:1247 [inline]
 __vhci_create_device drivers/bluetooth/hci_vhci.c:102 [inline]
 vhci_create_device+0x120/0x590 drivers/bluetooth/hci_vhci.c:153
 vhci_get_user drivers/bluetooth/hci_vhci.c:210 [inline]
 vhci_write+0x382/0x430 drivers/bluetooth/hci_vhci.c:290
 call_write_iter include/linux/fs.h:2172 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0xacd/0xe50 fs/read_write.c:594
 ksys_write+0x1a2/0x2c0 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 3570:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0xf1/0x270 mm/slub.c:4559
 hci_release_dev+0x149e/0x1620 net/bluetooth/hci_core.c:4096
 bt_host_release+0x7f/0x90 net/bluetooth/hci_sysfs.c:92
 device_release+0x91/0x1c0
 kobject_cleanup lib/kobject.c:713 [inline]
 kobject_release lib/kobject.c:744 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x224/0x460 lib/kobject.c:761
 vhci_release+0x7b/0xc0 drivers/bluetooth/hci_vhci.c:346
 __fput+0x3fe/0x8e0 fs/file_table.c:280
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x6a3/0x2480 kernel/exit.c:874
 do_group_exit+0x144/0x310 kernel/exit.c:996
 __do_sys_exit_group kernel/exit.c:1007 [inline]
 __se_sys_exit_group kernel/exit.c:1005 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1005
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 insert_work+0x54/0x3e0 kernel/workqueue.c:1366
 __queue_work+0x963/0xd00 kernel/workqueue.c:1532
 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1451
 expire_timers kernel/time/timer.c:1491 [inline]
 __run_timers+0x6a8/0x890 kernel/time/timer.c:1767
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
 __do_softirq kernel/softirq.c:592 [inline]
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638

Second to last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 insert_work+0x54/0x3e0 kernel/workqueue.c:1366
 __queue_work+0x963/0xd00 kernel/workqueue.c:1532
 queue_work_on+0x14b/0x250 kernel/workqueue.c:1559
 queue_work include/linux/workqueue.h:512 [inline]
 hci_recv_frame+0x18a/0x1e0 net/bluetooth/hci_core.c:4160
 vhci_get_user drivers/bluetooth/hci_vhci.c:194 [inline]
 vhci_write+0x31a/0x430 drivers/bluetooth/hci_vhci.c:290
 call_write_iter include/linux/fs.h:2172 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0xacd/0xe50 fs/read_write.c:594
 ksys_write+0x1a2/0x2c0 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff888015bf4000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 168 bytes inside of
 8192-byte region [ffff888015bf4000, ffff888015bf6000)
The buggy address belongs to the page:
page:ffffea000056fc00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x15bf0
head:ffffea000056fc00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 0000000100000001 ffff888011c42280
raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3561, ts 38032675983, free_ts 38028161499
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc_trace+0x1a0/0x290 mm/slub.c:3245
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 tomoyo_print_bprm security/tomoyo/audit.c:26 [inline]
 tomoyo_init_log+0x1140/0x1fe0 security/tomoyo/audit.c:264
 tomoyo_supervisor+0x3b8/0x12c0 security/tomoyo/common.c:2097
 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline]
 tomoyo_env_perm+0x174/0x210 security/tomoyo/environ.c:63
 tomoyo_environ security/tomoyo/domain.c:672 [inline]
 tomoyo_find_next_domain+0x137e/0x1cf0 security/tomoyo/domain.c:879
 tomoyo_bprm_check_security+0xdb/0x120 security/tomoyo/tomoyo.c:101
 security_bprm_check+0x5f/0xa0 security/security.c:868
 search_binary_handler fs/exec.c:1732 [inline]
 exec_binprm fs/exec.c:1785 [inline]
 bprm_execve+0x84e/0x17c0 fs/exec.c:1854
 do_execveat_common+0x583/0x720 fs/exec.c:1959
 do_execve fs/exec.c:2029 [inline]
 __do_sys_execve fs/exec.c:2105 [inline]
 __se_sys_execve fs/exec.c:2100 [inline]
 __x64_sys_execve+0x8e/0xa0 fs/exec.c:2100
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
 free_slab mm/slub.c:2015 [inline]
 discard_slab mm/slub.c:2021 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2507
 put_cpu_partial+0x132/0x1a0 mm/slub.c:2587
 do_slab_free mm/slub.c:3487 [inline]
 ___cache_free+0xe3/0x100 mm/slub.c:3506
 qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 __kmalloc+0x120/0x300 mm/slub.c:4403
 kmalloc include/linux/slab.h:596 [inline]
 tomoyo_realpath_from_path+0xd8/0x5e0 security/tomoyo/realpath.c:254
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x273/0x6b0 security/tomoyo/file.c:822
 security_inode_getattr+0xcf/0x120 security/security.c:1348
 vfs_getattr+0x26/0x360 fs/stat.c:157
 vfs_statx+0x18f/0x3b0 fs/stat.c:225
 vfs_fstatat fs/stat.c:243 [inline]
 __do_sys_newfstatat fs/stat.c:411 [inline]
 __se_sys_newfstatat fs/stat.c:405 [inline]
 __x64_sys_newfstatat+0x12c/0x1b0 fs/stat.c:405

Memory state around the buggy address:
 ffff888015bf3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888015bf4000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888015bf4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888015bf4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888015bf4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/30 00:12 linux-5.15.y fa93fa65db6e 9bd464fc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in hci_ncmd_timeout
* Struck through repros no longer work on HEAD.