syzbot


KASAN: slab-use-after-free Read in process_scheduled_works

Status: upstream: reported on 2024/11/26 00:01
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+06abfac864b72aafabe9@syzkaller.appspotmail.com
First crash: 127d, last: 6d00h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [kernel?] KASAN: slab-use-after-free Read in process_scheduled_works 0 (1) 2024/11/26 00:01

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in lock_release+0x151/0xa30 kernel/locking/lockdep.c:5862
Read of size 8 at addr ffff888034162338 by task kworker/1:5/5883

CPU: 1 UID: 0 PID: 5883 Comm: kworker/1:5 Not tainted 6.13.0-rc3-syzkaller-00180-g4f619d518db9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events l2cap_chan_timeout
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 lock_release+0x151/0xa30 kernel/locking/lockdep.c:5862
 __mutex_unlock_slowpath+0xe2/0x790 kernel/locking/mutex.c:896
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 8639:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4329
 kmalloc_noprof include/linux/slab.h:901 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 l2cap_conn_add+0xa9/0x8e0 net/bluetooth/l2cap_core.c:6860
 l2cap_chan_connect+0x623/0xeb0 net/bluetooth/l2cap_core.c:7051
 l2cap_sock_connect+0x5c9/0x800 net/bluetooth/l2cap_sock.c:256
 kernel_connect+0x10b/0x160 net/socket.c:3625
 rfcomm_session_create net/bluetooth/rfcomm/core.c:811 [inline]
 __rfcomm_dlc_open net/bluetooth/rfcomm/core.c:388 [inline]
 rfcomm_dlc_open+0x7cc/0x1270 net/bluetooth/rfcomm/core.c:431
 rfcomm_sock_connect+0x305/0x610 net/bluetooth/rfcomm/sock.c:409
 __sys_connect_file net/socket.c:2055 [inline]
 __sys_connect+0x288/0x2d0 net/socket.c:2074
 __do_sys_connect net/socket.c:2080 [inline]
 __se_sys_connect net/socket.c:2077 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2077
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 8461:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4613 [inline]
 kfree+0x196/0x430 mm/slub.c:4761
 hci_disconn_cfm include/net/bluetooth/hci_core.h:2075 [inline]
 hci_conn_hash_flush+0x1be/0x350 net/bluetooth/hci_conn.c:2698
 hci_dev_close_sync+0xa42/0x11c0 net/bluetooth/hci_sync.c:5212
 hci_dev_do_close net/bluetooth/hci_core.c:482 [inline]
 hci_unregister_dev+0x20b/0x510 net/bluetooth/hci_core.c:2697
 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:664
 __fput+0x23c/0xa50 fs/file_table.c:450
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa2f/0x28e0 kernel/exit.c:938
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096
 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888034162000
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 824 bytes inside of
 freed 1024-byte region [ffff888034162000, ffff888034162400)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x34160
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801ac41dc0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801ac41dc0 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea0000d05801 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 2993, tgid 2993 (kworker/u8:8), ts 71459123632, free_ts 71435563847
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556
 prep_new_page mm/page_alloc.c:1564 [inline]
 get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3474
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269
 alloc_slab_page+0x6a/0x110 mm/slub.c:2423
 allocate_slab+0x5a/0x2b0 mm/slub.c:2589
 new_slab mm/slub.c:2642 [inline]
 ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830
 __slab_alloc+0x58/0xa0 mm/slub.c:3920
 __slab_alloc_node mm/slub.c:3995 [inline]
 slab_alloc_node mm/slub.c:4156 [inline]
 __do_kmalloc_node mm/slub.c:4297 [inline]
 __kmalloc_noprof+0x2e6/0x4c0 mm/slub.c:4310
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 ieee802_11_parse_elems_full+0xdb/0x2880 net/mac80211/parse.c:958
 ieee802_11_parse_elems_crc net/mac80211/ieee80211_i.h:2384 [inline]
 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2391 [inline]
 ieee80211_inform_bss+0x15f/0x1080 net/mac80211/scan.c:79
 rdev_inform_bss net/wireless/rdev-ops.h:418 [inline]
 cfg80211_inform_single_bss_data+0xec1/0x2070 net/wireless/scan.c:2334
 cfg80211_inform_bss_data+0x3ce/0x5e80 net/wireless/scan.c:3189
 cfg80211_inform_bss_frame_data+0x3bb/0x720 net/wireless/scan.c:3284
 ieee80211_bss_info_update+0x8a7/0xbc0 net/mac80211/scan.c:226
 ieee80211_rx_bss_info net/mac80211/ibss.c:1101 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1580 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1969/0x2d70 net/mac80211/ibss.c:1607
page last free pid 5995 tgid 5995 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xd3f/0x1010 mm/page_alloc.c:2657
 discard_slab mm/slub.c:2688 [inline]
 __put_partials+0x160/0x1c0 mm/slub.c:3157
 put_cpu_partial+0x17c/0x250 mm/slub.c:3232
 __slab_free+0x290/0x380 mm/slub.c:4483
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4119 [inline]
 slab_alloc_node mm/slub.c:4168 [inline]
 kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4175
 getname_flags+0xb7/0x540 fs/namei.c:139
 getname_maybe_null include/linux/fs.h:2796 [inline]
 vfs_fstatat+0x3f/0x130 fs/stat.c:361
 __do_sys_newfstatat fs/stat.c:530 [inline]
 __se_sys_newfstatat fs/stat.c:524 [inline]
 __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:524
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888034162200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888034162280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888034162300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff888034162380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888034162400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/02 02:20 net 4f619d518db9 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Read in process_scheduled_works
2024/12/19 05:03 net 5c964c8a97c1 1432fc84 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Read in process_scheduled_works
2024/11/21 04:15 net 66418447d27b 4b25d554 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Read in process_scheduled_works
2025/03/22 06:22 net-next bfc17c165835 c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce KASAN: slab-use-after-free Read in process_scheduled_works
* Struck through repros no longer work on HEAD.