==================================================================
BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1639 [inline]
BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0xde7/0xf80 net/bluetooth/l2cap_core.c:7427
Read of size 8 at addr ffff88806035e480 by task kworker/u9:3/27493
CPU: 0 UID: 0 PID: 27493 Comm: kworker/u9:3 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: hci5 hci_rx_work
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1d0 mm/kasan/report.c:595
l2cap_conn_ready net/bluetooth/l2cap_core.c:1639 [inline]
l2cap_connect_cfm+0xde7/0xf80 net/bluetooth/l2cap_core.c:7427
hci_connect_cfm include/net/bluetooth/hci_core.h:2139 [inline]
le_conn_complete_evt+0x197c/0x1f60 net/bluetooth/hci_event.c:5865
hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5891
hci_le_meta_evt+0x34a/0x5f0 net/bluetooth/hci_event.c:7506
hci_event_func net/bluetooth/hci_event.c:7770 [inline]
hci_event_packet+0x51c/0xcd0 net/bluetooth/hci_event.c:7824
hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4077
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
process_scheduled_works kernel/workqueue.c:3385 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Allocated by task 27493:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
l2cap_chan_create+0x44/0x940 net/bluetooth/l2cap_core.c:445
l2cap_sock_alloc.constprop.0+0xf5/0x1e0 net/bluetooth/l2cap_sock.c:1934
l2cap_sock_new_connection_cb+0x101/0x260 net/bluetooth/l2cap_sock.c:1510
l2cap_connect_cfm+0x4e2/0xf80 net/bluetooth/l2cap_core.c:7410
hci_connect_cfm include/net/bluetooth/hci_core.h:2139 [inline]
le_conn_complete_evt+0x197c/0x1f60 net/bluetooth/hci_event.c:5865
hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5891
hci_le_meta_evt+0x34a/0x5f0 net/bluetooth/hci_event.c:7506
hci_event_func net/bluetooth/hci_event.c:7770 [inline]
hci_event_packet+0x51c/0xcd0 net/bluetooth/hci_event.c:7824
hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4077
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
process_scheduled_works kernel/workqueue.c:3385 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Freed by task 31244:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6246 [inline]
kfree+0x223/0x6c0 mm/slub.c:6561
l2cap_chan_destroy net/bluetooth/l2cap_core.c:491 [inline]
kref_put include/linux/kref.h:65 [inline]
l2cap_chan_put+0x235/0x300 net/bluetooth/l2cap_core.c:516
l2cap_sock_cleanup_listen+0x4d/0x2d0 net/bluetooth/l2cap_sock.c:1493
l2cap_sock_release+0x69/0x280 net/bluetooth/l2cap_sock.c:1451
__sock_release+0xb3/0x260 net/socket.c:722
sock_close+0x1c/0x30 net/socket.c:1514
__fput+0x3ff/0xb50 fs/file_table.c:510
task_work_run+0x150/0x240 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x706/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88806035e000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1152 bytes inside of
freed 2048-byte region [ffff88806035e000, ffff88806035e800)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88806035c000 pfn:0x60358
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88813fe2f000 ffffea0000c08c10 ffffea0001fe3010
raw: ffff88806035c000 0000000800080007 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813fe2f000 ffffea0000c08c10 ffffea0001fe3010
head: ffff88806035c000 0000000800080007 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5282, tgid 5282 (dhcpcd), ts 1057214353626, free_ts 1056793836802
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x153/0x170 mm/page_alloc.c:1858
prep_new_page mm/page_alloc.c:1866 [inline]
get_page_from_freelist+0x11a6/0x33b0 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5226
alloc_slab_page mm/slub.c:3278 [inline]
allocate_slab mm/slub.c:3467 [inline]
new_slab+0xa6/0x6c0 mm/slub.c:3525
refill_objects+0x277/0x420 mm/slub.c:7251
refill_sheaf mm/slub.c:2816 [inline]
__pcs_replace_empty_main+0x375/0x650 mm/slub.c:4651
alloc_from_pcs mm/slub.c:4749 [inline]
slab_alloc_node mm/slub.c:4883 [inline]
__do_kmalloc_node mm/slub.c:5294 [inline]
__kvmalloc_node_noprof+0x7da/0xa00 mm/slub.c:6828
kvmalloc_array_node_noprof include/linux/slab.h:1216 [inline]
__ptr_ring_init_queue_alloc_noprof include/linux/ptr_ring.h:481 [inline]
ptr_ring_init_noprof include/linux/ptr_ring.h:499 [inline]
page_pool_init net/core/page_pool.c:262 [inline]
page_pool_create_percpu+0x2e0/0xcd0 net/core/page_pool.c:347
nsim_create_page_pool drivers/net/netdevsim/netdev.c:429 [inline]
nsim_init_napi drivers/net/netdevsim/netdev.c:452 [inline]
nsim_open+0x38d/0xb90 drivers/net/netdevsim/netdev.c:508
__dev_open+0x3ad/0x8f0 net/core/dev.c:1702
__dev_change_flags+0x596/0x850 net/core/dev.c:9755
netif_change_flags+0x8d/0x160 net/core/dev.c:9818
dev_change_flags+0xba/0x260 net/core/dev_api.c:68
devinet_ioctl+0x110b/0x1f10 net/ipv4/devinet.c:1199
inet_ioctl+0x3aa/0x3f0 net/ipv4/af_inet.c:1011
sock_do_ioctl+0x118/0x280 net/socket.c:1313
page last free pid 24428 tgid 24428 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0x747/0x1040 mm/page_alloc.c:2943
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4569 [inline]
slab_alloc_node mm/slub.c:4898 [inline]
kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4905
vm_area_dup+0x27/0x8e0 mm/vma_init.c:123
__split_vma+0x18c/0xd90 mm/vma.c:516
split_vma mm/vma.c:599 [inline]
vma_modify+0x12ad/0x25c0 mm/vma.c:1699
vma_modify_flags+0x257/0x3d0 mm/vma.c:1719
mprotect_fixup+0x27a/0xe30 mm/mprotect.c:789
do_mprotect_pkey+0xa4b/0xef0 mm/mprotect.c:967
__do_sys_mprotect mm/mprotect.c:988 [inline]
__se_sys_mprotect mm/mprotect.c:985 [inline]
__x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:985
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88806035e380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88806035e400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88806035e480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88806035e500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88806035e580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
==================================================================
BUG: KASAN: wild-memory-access in instrument_atomic_read include/linux/instrumented.h:82 [inline]
BUG: KASAN: wild-memory-access in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_lock include/net/bluetooth/l2cap.h:829 [inline]
BUG: KASAN: wild-memory-access in l2cap_conn_ready net/bluetooth/l2cap_core.c:1641 [inline]
BUG: KASAN: wild-memory-access in l2cap_connect_cfm+0x7c0/0xf80 net/bluetooth/l2cap_core.c:7427
Read of size 4 at addr deacfffffffffc8c by task kworker/u9:3/27493
CPU: 0 UID: 0 PID: 27493 Comm: kworker/u9:3 Tainted: G B syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: hci5 hci_rx_work
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
kasan_report+0xdf/0x1d0 mm/kasan/report.c:595
check_region_inline mm/kasan/generic.c:186 [inline]
kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200
instrument_atomic_read include/linux/instrumented.h:82 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
l2cap_chan_lock include/net/bluetooth/l2cap.h:829 [inline]
l2cap_conn_ready net/bluetooth/l2cap_core.c:1641 [inline]
l2cap_connect_cfm+0x7c0/0xf80 net/bluetooth/l2cap_core.c:7427
hci_connect_cfm include/net/bluetooth/hci_core.h:2139 [inline]
le_conn_complete_evt+0x197c/0x1f60 net/bluetooth/hci_event.c:5865
hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5891
hci_le_meta_evt+0x34a/0x5f0 net/bluetooth/hci_event.c:7506
hci_event_func net/bluetooth/hci_event.c:7770 [inline]
hci_event_packet+0x51c/0xcd0 net/bluetooth/hci_event.c:7824
hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4077
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
process_scheduled_works kernel/workqueue.c:3385 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
==================================================================
Oops: general protection fault, probably for non-canonical address 0xfbd59bffffffff91: 0000 [#1] SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdeacfffffffffc88-0xdeacfffffffffc8f]
CPU: 0 UID: 0 PID: 27493 Comm: kworker/u9:3 Tainted: G B syzkaller #0 PREEMPT(full)
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: hci5 hci_rx_work
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:829 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1641 [inline]
RIP: 0010:l2cap_connect_cfm+0x7c7/0xf80 net/bluetooth/l2cap_core.c:7427
Code: 80 fb ff ff 49 39 c7 0f 84 29 01 00 00 e8 c1 3e 7c f7 49 8d 6e 0c be 04 00 00 00 48 89 ef e8 e0 09 e9 f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 f5
RSP: 0018:ffffc900049c7830 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffc9001a6c8000
RDX: 0000000000000000 RSI: ffffffff81c62ecd RDI: ffff88802b7f3d80
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88807bc3403d
R13: 0000000000000080 R14: deacfffffffffc80 R15: ffff888056f2e288
FS: 0000000000000000(0000) GS:ffff88812437a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f81cbec8d58 CR3: 0000000075904000 CR4: 0000000000350ef0
Call Trace:
hci_connect_cfm include/net/bluetooth/hci_core.h:2139 [inline]
le_conn_complete_evt+0x197c/0x1f60 net/bluetooth/hci_event.c:5865
hci_le_conn_complete_evt+0x23c/0x3a0 net/bluetooth/hci_event.c:5891
hci_le_meta_evt+0x34a/0x5f0 net/bluetooth/hci_event.c:7506
hci_event_func net/bluetooth/hci_event.c:7770 [inline]
hci_event_packet+0x51c/0xcd0 net/bluetooth/hci_event.c:7824
hci_rx_work+0x451/0xfc0 net/bluetooth/hci_core.c:4077
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
process_scheduled_works kernel/workqueue.c:3385 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:33 [inline]
RIP: 0010:l2cap_chan_lock include/net/bluetooth/l2cap.h:829 [inline]
RIP: 0010:l2cap_conn_ready net/bluetooth/l2cap_core.c:1641 [inline]
RIP: 0010:l2cap_connect_cfm+0x7c7/0xf80 net/bluetooth/l2cap_core.c:7427
Code: 80 fb ff ff 49 39 c7 0f 84 29 01 00 00 e8 c1 3e 7c f7 49 8d 6e 0c be 04 00 00 00 48 89 ef e8 e0 09 e9 f7 48 89 e8 48 c1 e8 03 <0f> b6 14 18 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 f5
RSP: 0018:ffffc900049c7830 EFLAGS: 00010213
RAX: 1bd59fffffffff91 RBX: dffffc0000000000 RCX: ffffc9001a6c8000
RDX: 0000000000000000 RSI: ffffffff81c62ecd RDI: ffff88802b7f3d80
RBP: deacfffffffffc8c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 3d3d3d3d3d3d3d3d R12: ffff88807bc3403d
R13: 0000000000000080 R14: deacfffffffffc80 R15: ffff888056f2e288
FS: 0000000000000000(0000) GS:ffff88812447a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ce3be8158 CR3: 00000000a2915000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
0: 49 39 c7 cmp %rax,%r15
3: 0f 84 29 01 00 00 je 0x132
9: e8 c1 3e 7c f7 call 0xf77c3ecf
e: 49 8d 6e 0c lea 0xc(%r14),%rbp
12: be 04 00 00 00 mov $0x4,%esi
17: 48 89 ef mov %rbp,%rdi
1a: e8 e0 09 e9 f7 call 0xf7e909ff
1f: 48 89 e8 mov %rbp,%rax
22: 48 c1 e8 03 shr $0x3,%rax
* 26: 0f b6 14 18 movzbl (%rax,%rbx,1),%edx <-- trapping instruction
2a: 48 89 e8 mov %rbp,%rax
2d: 83 e0 07 and $0x7,%eax
30: 83 c0 03 add $0x3,%eax
33: 38 d0 cmp %dl,%al
35: 7c 08 jl 0x3f
37: 84 d2 test %dl,%dl
39: 0f .byte 0xf
3a: 85 f5 test %esi,%ebp