syzbot


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

Status: upstream: reported on 2024/10/21 08:47
Subsystems: bluetooth
[Documentation on labels]
Reported-by: syzbot+a1595e656a83ea5b78eb@syzkaller.appspotmail.com
First crash: 227d, last: 1d01h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bluetooth?] KASAN: slab-use-after-free Read in bt_accept_unlink 0 (1) 2024/10/21 08:47
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 BUG: corrupted list in bt_accept_unlink 1 38d 38d 0/3 upstream: reported on 2025/04/09 00:51
upstream general protection fault in bt_accept_unlink (2) bluetooth 1 1536d 1531d 0/28 auto-closed as invalid on 2021/07/01 06:33
upstream BUG: corrupted list in bt_accept_unlink bluetooth syz error error 1 1736d 1736d 0/28 auto-obsoleted due to no activity on 2022/09/07 16:27
linux-4.14 BUG: corrupted list in bt_accept_unlink syz unreliable 1 1621d 1741d 0/1 upstream: reported syz repro on 2020/08/09 08:38

Sample crash report:
Bluetooth: hci0: Opcode 0x0c1a failed: -4
Bluetooth: hci0: Opcode 0x0406 failed: -4
Bluetooth: hci2: Opcode 0x0c1a failed: -4
Bluetooth: hci2: Opcode 0x0406 failed: -4
Bluetooth: hci3: Opcode 0x0c1a failed: -4
Bluetooth: hci3: Opcode 0x0406 failed: -4
Bluetooth: hci3: Opcode 0x0406 failed: -4
==================================================================
BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x1d4/0x200 lib/list_debug.c:62
Read of size 8 at addr ffff88807d1a0558 by task syz.1.624/8576

CPU: 1 UID: 0 PID: 8576 Comm: syz.1.624 Not tainted 6.15.0-rc6-syzkaller-00188-gfee3e843b309 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xc3/0x670 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 __list_del_entry_valid_or_report+0x1d4/0x200 lib/list_debug.c:62
 __list_del_entry_valid include/linux/list.h:124 [inline]
 __list_del_entry include/linux/list.h:215 [inline]
 list_del_init include/linux/list.h:287 [inline]
 bt_accept_unlink+0x34/0x2e0 net/bluetooth/af_bluetooth.c:256
 l2cap_sock_teardown_cb+0x1a3/0x3c0 net/bluetooth/l2cap_sock.c:1613
 l2cap_chan_del+0xba/0x8f0 net/bluetooth/l2cap_core.c:655
 l2cap_conn_del+0x37a/0x730 net/bluetooth/l2cap_core.c:1786
 l2cap_connect_cfm+0x9e1/0xf80 net/bluetooth/l2cap_core.c:7234
 hci_connect_cfm include/net/bluetooth/hci_core.h:2053 [inline]
 hci_conn_failed+0x1bd/0x330 net/bluetooth/hci_conn.c:1269
 hci_abort_conn_sync+0x740/0xb40 net/bluetooth/hci_sync.c:5616
 hci_disconnect_all_sync.constprop.0+0x104/0x3c0 net/bluetooth/hci_sync.c:5639
 hci_suspend_sync+0x770/0xab0 net/bluetooth/hci_sync.c:6116
 hci_suspend_dev+0x308/0x500 net/bluetooth/hci_core.c:2812
 hci_suspend_notifier+0x28d/0x2f0 net/bluetooth/hci_core.c:2392
 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85
 notifier_call_chain_robust kernel/notifier.c:120 [inline]
 blocking_notifier_call_chain_robust kernel/notifier.c:345 [inline]
 blocking_notifier_call_chain_robust+0xc8/0x160 kernel/notifier.c:333
 pm_notifier_call_chain_robust+0x27/0x60 kernel/power/main.c:102
 snapshot_open+0x189/0x2b0 kernel/power/user.c:77
 misc_open+0x35d/0x420 drivers/char/misc.c:179
 chrdev_open+0x231/0x6a0 fs/char_dev.c:414
 do_dentry_open+0x741/0x1c10 fs/open.c:956
 vfs_open+0x82/0x3f0 fs/open.c:1086
 do_open fs/namei.c:3880 [inline]
 path_openat+0x1e5e/0x2d40 fs/namei.c:4039
 do_filp_open+0x20b/0x470 fs/namei.c:4066
 do_sys_openat2+0x11b/0x1d0 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_openat fs/open.c:1460 [inline]
 __se_sys_openat fs/open.c:1455 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1455
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ea298e969
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5ea3760038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f5ea2bb6160 RCX: 00007f5ea298e969
RDX: 0000000000008800 RSI: 00002000000001c0 RDI: ffffffffffffff9c
RBP: 00007f5ea2a10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f5ea2bb6160 R15: 00007ffe40365cc8
 </TASK>

Allocated by task 7749:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kmalloc_node_track_caller_noprof+0x221/0x510 mm/slub.c:4346
 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:599
 __alloc_skb+0x166/0x380 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1340 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x2b1/0xcf0 drivers/net/netdevsim/dev.c:851
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 7749:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2380 [inline]
 slab_free mm/slub.c:4642 [inline]
 kfree+0x2b6/0x4d0 mm/slub.c:4841
 skb_kfree_head net/core/skbuff.c:1058 [inline]
 skb_free_head+0x108/0x1d0 net/core/skbuff.c:1070
 skb_release_data+0x7a5/0x960 net/core/skbuff.c:1097
 skb_release_all net/core/skbuff.c:1162 [inline]
 __kfree_skb net/core/skbuff.c:1176 [inline]
 consume_skb net/core/skbuff.c:1408 [inline]
 consume_skb+0xbf/0x100 net/core/skbuff.c:1402
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
 nsim_dev_trap_report_work+0x8bd/0xcf0 drivers/net/netdevsim/dev.c:851
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88807d1a0000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1368 bytes inside of
 freed 4096-byte region [ffff88807d1a0000, ffff88807d1a1000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d1a0
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 ffff88801b442140 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b442140 dead000000000122 0000000000000000
head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0001f46801 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 7749, tgid 7749 (kworker/u8:10), ts 255304635042, free_ts 255193836531
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0x135c/0x3920 mm/page_alloc.c:3688
 __alloc_frozen_pages_noprof+0x263/0x23a0 mm/page_alloc.c:4970
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2450 [inline]
 allocate_slab mm/slub.c:2618 [inline]
 new_slab+0x244/0x340 mm/slub.c:2672
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3858
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3948
 __slab_alloc_node mm/slub.c:4023 [inline]
 slab_alloc_node mm/slub.c:4184 [inline]
 __do_kmalloc_node mm/slub.c:4326 [inline]
 __kmalloc_node_track_caller_noprof+0x2ee/0x510 mm/slub.c:4346
 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:599
 __alloc_skb+0x166/0x380 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1340 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x2b1/0xcf0 drivers/net/netdevsim/dev.c:851
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page last free pid 5809 tgid 5809 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0x69d/0xff0 mm/page_alloc.c:2725
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3185
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 __do_kmalloc_node mm/slub.c:4326 [inline]
 __kmalloc_noprof+0x1d4/0x510 mm/slub.c:4339
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 tomoyo_encode2+0x100/0x3e0 security/tomoyo/realpath.c:45
 tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x18f/0x6e0 security/tomoyo/realpath.c:283
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x2ab/0x3c0 security/tomoyo/file.c:771
 tomoyo_file_open+0x6b/0x90 security/tomoyo/tomoyo.c:334
 security_file_open+0x84/0x1e0 security/security.c:3114
 do_dentry_open+0x596/0x1c10 fs/open.c:933
 vfs_open+0x82/0x3f0 fs/open.c:1086
 do_open fs/namei.c:3880 [inline]
 path_openat+0x1e5e/0x2d40 fs/namei.c:4039
 do_filp_open+0x20b/0x470 fs/namei.c:4066

Memory state around the buggy address:
 ffff88807d1a0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d1a0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807d1a0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff88807d1a0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d1a0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (32):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/16 05:41 upstream fee3e843b309 cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/05/16 02:36 upstream fee3e843b309 cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/04/23 11:14 upstream bc3372351d0c 53a8b9bd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/04/13 13:18 upstream 7cdabafc0012 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/04/08 18:07 upstream 0af2f6be1b42 a775275d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/02/17 17:43 upstream 0ad2507d5d93 9be4ace3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/02/08 00:03 upstream 7ee983c850b4 a4f327c2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/01/16 05:15 upstream 619f0b6fad52 968edaf4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/04/03 08:36 upstream a1b5bd45d4ee 996a9618 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in bt_accept_unlink
2025/03/01 04:22 upstream 276f98efb64a 67cf5345 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in bt_accept_unlink
2025/01/16 22:26 upstream ce69b4019001 f9e07a6e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in bt_accept_unlink
2024/10/27 14:44 upstream 850925a8133c 65e8686b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in bt_accept_unlink
2024/10/10 10:49 upstream d3d1556696c1 a156c552 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in bt_accept_unlink
2024/10/01 18:11 upstream e32cde8d2bd7 e9f6e118 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-use-after-free Read in bt_accept_unlink
2025/02/15 02:47 upstream 04f41cbf03ec 40a34ec9 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-use-after-free Read in bt_accept_unlink
2025/02/11 19:48 upstream febbc555cf0f f2baddf5 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-use-after-free Read in bt_accept_unlink
2025/01/28 17:15 upstream 805ba04cb7cc ac37c1f8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-use-after-free Read in bt_accept_unlink
2025/02/15 19:38 linux-next 0ae0fa3bf0b4 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/02/11 22:13 linux-next df5d6180169a f2baddf5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in bt_accept_unlink
2024/12/07 21:44 linux-next af2ea8ab7a54 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in bt_accept_unlink
2024/11/22 18:55 linux-next cfba9f07a1d6 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Read in bt_accept_unlink
2025/04/09 05:51 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 0af2f6be1b42 b133e63a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-use-after-free Read in bt_accept_unlink
2024/11/21 22:47 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7b1d1d4cfac0 4b25d554 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-use-after-free Read in bt_accept_unlink
2025/05/16 02:35 upstream fee3e843b309 cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: corrupted list in bt_accept_unlink
2025/05/15 18:55 upstream 546bce579204 d6b2ee52 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-out-of-bounds Read in bt_accept_unlink
2025/04/08 20:25 upstream 0af2f6be1b42 a775275d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: corrupted list in bt_accept_unlink
2024/11/14 00:56 upstream f1b785f4c787 a8c99394 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-out-of-bounds Read in bt_accept_unlink
2025/04/07 11:24 upstream 0af2f6be1b42 2f0c9720 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream KASAN: slab-out-of-bounds Read in bt_accept_unlink
2025/04/07 05:28 upstream 16cd1c265776 1c65791e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-out-of-bounds Read in bt_accept_unlink
2025/02/05 02:52 upstream d009de7d5428 44c01590 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-out-of-bounds Read in bt_accept_unlink
2025/01/21 14:39 upstream 3d3a9c8b89d4 6e87cfa2 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-out-of-bounds Read in bt_accept_unlink
2024/12/21 04:48 upstream e9b8ffafd20a d7f584ee .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: corrupted list in bt_accept_unlink
* Struck through repros no longer work on HEAD.