[v6.6] KASAN: slab-use-after-free Read in bt_accept_unlink (2)
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syzbot
Jul 6, 2026, 4:50:24 PM (6 days ago) Jul 6
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: da47cbc25466 Linux 6.6.144
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15f62b39580000
kernel config: https://syzkaller.appspot.com/x/.config?x=938110aa66424b94
dashboard link: https://syzkaller.appspot.com/bug?extid=5505c8db36dba9924cf3
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a9e82134d7e6/disk-da47cbc2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/296a86743157/vmlinux-da47cbc2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c5adb532f254/bzImage-da47cbc2.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5505c8...@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: slab-use-after-free in __lock_acquire+0x10c/0x7d80 kernel/locking/lockdep.c:5005
Read of size 8 at addr ffff8880782b2540 by task syz.0.5130/23667
CPU: 0 PID: 23667 Comm: syz.0.5130 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
<TASK>
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0xa8/0x210 mm/kasan/report.c:468
kasan_report+0x117/0x150 mm/kasan/report.c:581
__lock_acquire+0x10c/0x7d80 kernel/locking/lockdep.c:5005
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
bt_accept_unlink+0x63/0x290 net/bluetooth/af_bluetooth.c:262
l2cap_sock_teardown_cb+0x17e/0x450 net/bluetooth/l2cap_sock.c:1649
l2cap_chan_del+0xaf/0x5e0 net/bluetooth/l2cap_core.c:658
l2cap_conn_del+0x38c/0x670 net/bluetooth/l2cap_core.c:1786
hci_disconn_cfm include/net/bluetooth/hci_core.h:2014 [inline]
hci_conn_hash_flush+0xff/0x220 net/bluetooth/hci_conn.c:2564
hci_dev_close_sync+0x9a1/0x1130 net/bluetooth/hci_sync.c:5305
hci_dev_do_close net/bluetooth/hci_core.c:523 [inline]
hci_unregister_dev+0x21a/0x500 net/bluetooth/hci_core.c:2709
vhci_release+0x170/0x1c0 drivers/bluetooth/hci_vhci.c:691
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x986/0x2530 kernel/exit.c:884
do_group_exit+0x22d/0x2f0 kernel/exit.c:1026
get_signal+0x12a6/0x1390 kernel/signal.c:2903
arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6d50b5e68e
Code: Unable to access opcode bytes at 0x7f6d50b5e664.
RSP: 002b:00007f6d51a12f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f6d51a136c0 RCX: 00007f6d50b5e68e
RDX: 00007f6d51a12fb0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6d50c33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6d50e26128 R14: 00007f6d50e26090 R15: 00007ffc6422d338
</TASK>
Allocated by task 32107:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
____kasan_kmalloc mm/kasan/common.c:375 [inline]
__kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384
kasan_kmalloc include/linux/kasan.h:198 [inline]
__do_kmalloc_node mm/slab_common.c:1007 [inline]
__kmalloc_node_track_caller+0xb4/0x230 mm/slab_common.c:1027
kmalloc_reserve+0x116/0x240 net/core/skbuff.c:584
pskb_expand_head+0x17a/0x1150 net/core/skbuff.c:2101
__bpf_try_make_writable net/core/filter.c:1682 [inline]
bpf_try_make_writable net/core/filter.c:1688 [inline]
bpf_try_make_head_writable net/core/filter.c:1696 [inline]
____bpf_clone_redirect net/core/filter.c:2483 [inline]
bpf_clone_redirect+0x1e6/0x4a0 net/core/filter.c:2452
0xffffffffa00088b5
bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline]
__bpf_prog_run include/linux/filter.h:616 [inline]
bpf_prog_run include/linux/filter.h:623 [inline]
bpf_test_run+0x2df/0x870 net/bpf/test_run.c:424
bpf_prog_test_run_skb+0xdbb/0x18f0 net/bpf/test_run.c:1089
bpf_prog_test_run+0x31f/0x390 kernel/bpf/syscall.c:4132
__sys_bpf+0x49d/0x890 kernel/bpf/syscall.c:5495
__do_sys_bpf kernel/bpf/syscall.c:5581 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5579 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Freed by task 32107:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
__kmem_cache_free+0xba/0x1f0 mm/slub.c:3843
skb_kfree_head net/core/skbuff.c:946 [inline]
skb_free_head net/core/skbuff.c:958 [inline]
skb_release_data+0x609/0x7f0 net/core/skbuff.c:988
skb_release_all net/core/skbuff.c:1054 [inline]
kfree_skb_add_bulk net/core/skbuff.c:1125 [inline]
kfree_skb_list_reason+0x264/0x460 net/core/skbuff.c:1147
__dev_xmit_skb net/core/dev.c:3950 [inline]
__dev_queue_xmit+0x1f87/0x3630 net/core/dev.c:4416
dev_queue_xmit include/linux/netdevice.h:3113 [inline]
neigh_hh_output include/net/neighbour.h:527 [inline]
neigh_output include/net/neighbour.h:541 [inline]
ip_finish_output2+0xd4f/0x1260 net/ipv4/ip_output.c:235
NF_HOOK_COND include/linux/netfilter.h:293 [inline]
ip_output+0x2a5/0x3a0 net/ipv4/ip_output.c:436
iptunnel_xmit+0x4d0/0x910 net/ipv4/ip_tunnel_core.c:82
ip_tunnel_xmit+0x1d18/0x25b0 net/ipv4/ip_tunnel.c:844
__gre_xmit net/ipv4/ip_gre.c:478 [inline]
ipgre_xmit+0x7eb/0xb70 net/ipv4/ip_gre.c:674
__netdev_start_xmit include/linux/netdevice.h:4943 [inline]
netdev_start_xmit include/linux/netdevice.h:4957 [inline]
xmit_one net/core/dev.c:3644 [inline]
dev_hard_start_xmit+0x269/0x790 net/core/dev.c:3660
__dev_queue_xmit+0x198c/0x3630 net/core/dev.c:4454
dev_queue_xmit include/linux/netdevice.h:3113 [inline]
__bpf_tx_skb+0x181/0x260 net/core/filter.c:2154
____bpf_clone_redirect net/core/filter.c:2489 [inline]
bpf_clone_redirect+0x315/0x4a0 net/core/filter.c:2452
0xffffffffa00088b5
bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline]
__bpf_prog_run include/linux/filter.h:616 [inline]
bpf_prog_run include/linux/filter.h:623 [inline]
bpf_test_run+0x2df/0x870 net/bpf/test_run.c:424
bpf_prog_test_run_skb+0xdbb/0x18f0 net/bpf/test_run.c:1089
bpf_prog_test_run+0x31f/0x390 kernel/bpf/syscall.c:4132
__sys_bpf+0x49d/0x890 kernel/bpf/syscall.c:5495
__do_sys_bpf kernel/bpf/syscall.c:5581 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5579 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46
__kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
__call_rcu_common kernel/rcu/tree.c:2721 [inline]
call_rcu+0x153/0x900 kernel/rcu/tree.c:2837
netlink_release+0x167e/0x1a70 net/netlink/af_netlink.c:801
__sock_release net/socket.c:659 [inline]
sock_close+0xa7/0x210 net/socket.c:1421
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Second to last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46
__kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
__call_rcu_common kernel/rcu/tree.c:2721 [inline]
call_rcu+0x153/0x900 kernel/rcu/tree.c:2837
netlink_release+0x167e/0x1a70 net/netlink/af_netlink.c:801
__sock_release net/socket.c:659 [inline]
sock_close+0xa7/0x210 net/socket.c:1421
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
The buggy address belongs to the object at ffff8880782b2000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1344 bytes inside of
freed 2048-byte region [ffff8880782b2000, ffff8880782b2800)
The buggy address belongs to the physical page:
page:ffffea0001e0ac00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x782b0
head:ffffea0001e0ac00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888017c42000 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000080008 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 14328, tgid 14318 (syz.2.2471), ts 452172064999, free_ts 447266597917
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582
prep_new_page mm/page_alloc.c:1589 [inline]
get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221
__alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501
alloc_slab_page+0x5d/0x180 mm/slub.c:1881
allocate_slab mm/slub.c:2028 [inline]
new_slab+0x87/0x2d0 mm/slub.c:2081
___slab_alloc+0xc5c/0x12f0 mm/slub.c:3253
__slab_alloc mm/slub.c:3339 [inline]
__slab_alloc_node mm/slub.c:3392 [inline]
slab_alloc_node mm/slub.c:3485 [inline]
__kmem_cache_alloc_node+0x11f/0x250 mm/slub.c:3534
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc_node+0xa6/0x240 mm/slab_common.c:1014
kmalloc_node include/linux/slab.h:620 [inline]
kzalloc_node include/linux/slab.h:732 [inline]
qdisc_alloc+0x95/0xa40 net/sched/sch_generic.c:951
qdisc_create_dflt+0x63/0x430 net/sched/sch_generic.c:1012
mq_init+0x2c7/0x660 net/sched/sch_mq.c:90
qdisc_create_dflt+0x11e/0x430 net/sched/sch_generic.c:1019
attach_default_qdiscs net/sched/sch_generic.c:1199 [inline]
dev_activate+0x1e0/0x1160 net/sched/sch_generic.c:1253
__dev_open+0x347/0x430 net/core/dev.c:1528
__dev_change_flags+0x1e8/0x6a0 net/core/dev.c:8723
dev_change_flags+0x7c/0x1a0 net/core/dev.c:8795
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1182 [inline]
free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366
free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459
napi_frag_unref include/linux/skbuff.h:3539 [inline]
skb_release_data+0x3ca/0x7f0 net/core/skbuff.c:982
skb_release_all net/core/skbuff.c:1054 [inline]
__kfree_skb+0x57/0x70 net/core/skbuff.c:1068
__tcp_close+0x216/0xdd0 net/ipv4/tcp.c:2822
tcp_close+0x28/0x110 net/ipv4/tcp.c:2966
tls_sk_proto_close+0x69e/0x930 net/tls/tls_main.c:396
inet_release+0x13d/0x180 net/ipv4/af_inet.c:434
__sock_release net/socket.c:659 [inline]
sock_close+0xa7/0x210 net/socket.c:1421
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Memory state around the buggy address:
ffff8880782b2400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880782b2480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880782b2500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880782b2580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880782b2600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
syzbot found the following issue on:
HEAD commit: da47cbc25466 Linux 6.6.144
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15f62b39580000
kernel config: https://syzkaller.appspot.com/x/.config?x=938110aa66424b94
dashboard link: https://syzkaller.appspot.com/bug?extid=5505c8db36dba9924cf3
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a9e82134d7e6/disk-da47cbc2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/296a86743157/vmlinux-da47cbc2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c5adb532f254/bzImage-da47cbc2.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5505c8...@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: slab-use-after-free in __lock_acquire+0x10c/0x7d80 kernel/locking/lockdep.c:5005
Read of size 8 at addr ffff8880782b2540 by task syz.0.5130/23667
CPU: 0 PID: 23667 Comm: syz.0.5130 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
<TASK>
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0xa8/0x210 mm/kasan/report.c:468
kasan_report+0x117/0x150 mm/kasan/report.c:581
__lock_acquire+0x10c/0x7d80 kernel/locking/lockdep.c:5005
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
bt_accept_unlink+0x63/0x290 net/bluetooth/af_bluetooth.c:262
l2cap_sock_teardown_cb+0x17e/0x450 net/bluetooth/l2cap_sock.c:1649
l2cap_chan_del+0xaf/0x5e0 net/bluetooth/l2cap_core.c:658
l2cap_conn_del+0x38c/0x670 net/bluetooth/l2cap_core.c:1786
hci_disconn_cfm include/net/bluetooth/hci_core.h:2014 [inline]
hci_conn_hash_flush+0xff/0x220 net/bluetooth/hci_conn.c:2564
hci_dev_close_sync+0x9a1/0x1130 net/bluetooth/hci_sync.c:5305
hci_dev_do_close net/bluetooth/hci_core.c:523 [inline]
hci_unregister_dev+0x21a/0x500 net/bluetooth/hci_core.c:2709
vhci_release+0x170/0x1c0 drivers/bluetooth/hci_vhci.c:691
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x986/0x2530 kernel/exit.c:884
do_group_exit+0x22d/0x2f0 kernel/exit.c:1026
get_signal+0x12a6/0x1390 kernel/signal.c:2903
arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6d50b5e68e
Code: Unable to access opcode bytes at 0x7f6d50b5e664.
RSP: 002b:00007f6d51a12f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f6d51a136c0 RCX: 00007f6d50b5e68e
RDX: 00007f6d51a12fb0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6d50c33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6d50e26128 R14: 00007f6d50e26090 R15: 00007ffc6422d338
</TASK>
Allocated by task 32107:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
____kasan_kmalloc mm/kasan/common.c:375 [inline]
__kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384
kasan_kmalloc include/linux/kasan.h:198 [inline]
__do_kmalloc_node mm/slab_common.c:1007 [inline]
__kmalloc_node_track_caller+0xb4/0x230 mm/slab_common.c:1027
kmalloc_reserve+0x116/0x240 net/core/skbuff.c:584
pskb_expand_head+0x17a/0x1150 net/core/skbuff.c:2101
__bpf_try_make_writable net/core/filter.c:1682 [inline]
bpf_try_make_writable net/core/filter.c:1688 [inline]
bpf_try_make_head_writable net/core/filter.c:1696 [inline]
____bpf_clone_redirect net/core/filter.c:2483 [inline]
bpf_clone_redirect+0x1e6/0x4a0 net/core/filter.c:2452
0xffffffffa00088b5
bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline]
__bpf_prog_run include/linux/filter.h:616 [inline]
bpf_prog_run include/linux/filter.h:623 [inline]
bpf_test_run+0x2df/0x870 net/bpf/test_run.c:424
bpf_prog_test_run_skb+0xdbb/0x18f0 net/bpf/test_run.c:1089
bpf_prog_test_run+0x31f/0x390 kernel/bpf/syscall.c:4132
__sys_bpf+0x49d/0x890 kernel/bpf/syscall.c:5495
__do_sys_bpf kernel/bpf/syscall.c:5581 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5579 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Freed by task 32107:
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
__kmem_cache_free+0xba/0x1f0 mm/slub.c:3843
skb_kfree_head net/core/skbuff.c:946 [inline]
skb_free_head net/core/skbuff.c:958 [inline]
skb_release_data+0x609/0x7f0 net/core/skbuff.c:988
skb_release_all net/core/skbuff.c:1054 [inline]
kfree_skb_add_bulk net/core/skbuff.c:1125 [inline]
kfree_skb_list_reason+0x264/0x460 net/core/skbuff.c:1147
__dev_xmit_skb net/core/dev.c:3950 [inline]
__dev_queue_xmit+0x1f87/0x3630 net/core/dev.c:4416
dev_queue_xmit include/linux/netdevice.h:3113 [inline]
neigh_hh_output include/net/neighbour.h:527 [inline]
neigh_output include/net/neighbour.h:541 [inline]
ip_finish_output2+0xd4f/0x1260 net/ipv4/ip_output.c:235
NF_HOOK_COND include/linux/netfilter.h:293 [inline]
ip_output+0x2a5/0x3a0 net/ipv4/ip_output.c:436
iptunnel_xmit+0x4d0/0x910 net/ipv4/ip_tunnel_core.c:82
ip_tunnel_xmit+0x1d18/0x25b0 net/ipv4/ip_tunnel.c:844
__gre_xmit net/ipv4/ip_gre.c:478 [inline]
ipgre_xmit+0x7eb/0xb70 net/ipv4/ip_gre.c:674
__netdev_start_xmit include/linux/netdevice.h:4943 [inline]
netdev_start_xmit include/linux/netdevice.h:4957 [inline]
xmit_one net/core/dev.c:3644 [inline]
dev_hard_start_xmit+0x269/0x790 net/core/dev.c:3660
__dev_queue_xmit+0x198c/0x3630 net/core/dev.c:4454
dev_queue_xmit include/linux/netdevice.h:3113 [inline]
__bpf_tx_skb+0x181/0x260 net/core/filter.c:2154
____bpf_clone_redirect net/core/filter.c:2489 [inline]
bpf_clone_redirect+0x315/0x4a0 net/core/filter.c:2452
0xffffffffa00088b5
bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline]
__bpf_prog_run include/linux/filter.h:616 [inline]
bpf_prog_run include/linux/filter.h:623 [inline]
bpf_test_run+0x2df/0x870 net/bpf/test_run.c:424
bpf_prog_test_run_skb+0xdbb/0x18f0 net/bpf/test_run.c:1089
bpf_prog_test_run+0x31f/0x390 kernel/bpf/syscall.c:4132
__sys_bpf+0x49d/0x890 kernel/bpf/syscall.c:5495
__do_sys_bpf kernel/bpf/syscall.c:5581 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5579 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5579
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46
__kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
__call_rcu_common kernel/rcu/tree.c:2721 [inline]
call_rcu+0x153/0x900 kernel/rcu/tree.c:2837
netlink_release+0x167e/0x1a70 net/netlink/af_netlink.c:801
__sock_release net/socket.c:659 [inline]
sock_close+0xa7/0x210 net/socket.c:1421
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Second to last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46
__kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
__call_rcu_common kernel/rcu/tree.c:2721 [inline]
call_rcu+0x153/0x900 kernel/rcu/tree.c:2837
netlink_release+0x167e/0x1a70 net/netlink/af_netlink.c:801
__sock_release net/socket.c:659 [inline]
sock_close+0xa7/0x210 net/socket.c:1421
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
The buggy address belongs to the object at ffff8880782b2000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1344 bytes inside of
freed 2048-byte region [ffff8880782b2000, ffff8880782b2800)
The buggy address belongs to the physical page:
page:ffffea0001e0ac00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x782b0
head:ffffea0001e0ac00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888017c42000 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000080008 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 14328, tgid 14318 (syz.2.2471), ts 452172064999, free_ts 447266597917
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582
prep_new_page mm/page_alloc.c:1589 [inline]
get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221
__alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501
alloc_slab_page+0x5d/0x180 mm/slub.c:1881
allocate_slab mm/slub.c:2028 [inline]
new_slab+0x87/0x2d0 mm/slub.c:2081
___slab_alloc+0xc5c/0x12f0 mm/slub.c:3253
__slab_alloc mm/slub.c:3339 [inline]
__slab_alloc_node mm/slub.c:3392 [inline]
slab_alloc_node mm/slub.c:3485 [inline]
__kmem_cache_alloc_node+0x11f/0x250 mm/slub.c:3534
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc_node+0xa6/0x240 mm/slab_common.c:1014
kmalloc_node include/linux/slab.h:620 [inline]
kzalloc_node include/linux/slab.h:732 [inline]
qdisc_alloc+0x95/0xa40 net/sched/sch_generic.c:951
qdisc_create_dflt+0x63/0x430 net/sched/sch_generic.c:1012
mq_init+0x2c7/0x660 net/sched/sch_mq.c:90
qdisc_create_dflt+0x11e/0x430 net/sched/sch_generic.c:1019
attach_default_qdiscs net/sched/sch_generic.c:1199 [inline]
dev_activate+0x1e0/0x1160 net/sched/sch_generic.c:1253
__dev_open+0x347/0x430 net/core/dev.c:1528
__dev_change_flags+0x1e8/0x6a0 net/core/dev.c:8723
dev_change_flags+0x7c/0x1a0 net/core/dev.c:8795
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1182 [inline]
free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366
free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459
napi_frag_unref include/linux/skbuff.h:3539 [inline]
skb_release_data+0x3ca/0x7f0 net/core/skbuff.c:982
skb_release_all net/core/skbuff.c:1054 [inline]
__kfree_skb+0x57/0x70 net/core/skbuff.c:1068
__tcp_close+0x216/0xdd0 net/ipv4/tcp.c:2822
tcp_close+0x28/0x110 net/ipv4/tcp.c:2966
tls_sk_proto_close+0x69e/0x930 net/tls/tls_main.c:396
inet_release+0x13d/0x180 net/ipv4/af_inet.c:434
__sock_release net/socket.c:659 [inline]
sock_close+0xa7/0x210 net/socket.c:1421
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Memory state around the buggy address:
ffff8880782b2400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880782b2480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880782b2500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880782b2580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880782b2600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
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