[v6.1] KASAN: invalid-free in hci_req_sync_complete

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6741e066ec76 Linux 6.1.87
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15981dd7180000
kernel config: https://syzkaller.appspot.com/x/.config?x=5d37120947ebed5a
dashboard link: https://syzkaller.appspot.com/bug?extid=c68cf32df83b2b1717ff
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e09aa9dab3c8/disk-6741e066.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4176a4f5a4d5/vmlinux-6741e066.xz
kernel image: https://storage.googleapis.com/syzbot-assets/970367753980/Image-6741e066.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c68cf3...@syzkaller.appspotmail.com

Bluetooth: hci1: unexpected cc 0x0c38 length: 249 > 2
==================================================================
BUG: KASAN: double-free in kfree_skbmem+0x10c/0x19c
Free of addr ffff0000ed5e7780 by task kworker/u5:6/4251

CPU: 0 PID: 4251 Comm: kworker/u5:6 Not tainted 6.1.87-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: hci1 hci_rx_work
Call trace:
dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:284 [inline]
print_report+0x174/0x4c0 mm/kasan/report.c:395
kasan_report_invalid_free+0xc4/0x114 mm/kasan/report.c:460
____kasan_slab_free+0x170/0x1c0 mm/kasan/common.c:225
__kasan_slab_free+0x18/0x28 mm/kasan/common.c:244
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1724 [inline]
slab_free_freelist_hook mm/slub.c:1750 [inline]
slab_free mm/slub.c:3661 [inline]
kmem_cache_free+0x2f0/0x588 mm/slub.c:3683
kfree_skbmem+0x10c/0x19c
__kfree_skb net/core/skbuff.c:871 [inline]
kfree_skb_reason+0x1ac/0x47c net/core/skbuff.c:893
kfree_skb include/linux/skbuff.h:1220 [inline]
hci_req_sync_complete+0xcc/0x258 net/bluetooth/hci_request.c:109
hci_event_packet+0xbd4/0x109c net/bluetooth/hci_event.c:7601
hci_rx_work+0x318/0xa68 net/bluetooth/hci_core.c:4130
process_one_work+0x7ac/0x1404 kernel/workqueue.c:2292
worker_thread+0x8e4/0xfec kernel/workqueue.c:2439
kthread+0x250/0x2d8 kernel/kthread.c:376
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864

Allocated by task 4249:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
__kasan_slab_alloc+0x74/0x8c mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x74/0x458 mm/slab.h:737
slab_alloc_node mm/slub.c:3398 [inline]
slab_alloc mm/slub.c:3406 [inline]
__kmem_cache_alloc_lru mm/slub.c:3413 [inline]
kmem_cache_alloc+0x230/0x37c mm/slub.c:3422
skb_clone+0x19c/0x304 net/core/skbuff.c:1660
hci_send_cmd_sync net/bluetooth/hci_core.c:4179 [inline]
hci_cmd_work+0x174/0x568 net/bluetooth/hci_core.c:4199
process_one_work+0x7ac/0x1404 kernel/workqueue.c:2292
worker_thread+0x8e4/0xfec kernel/workqueue.c:2439
kthread+0x250/0x2d8 kernel/kthread.c:376
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864

Freed by task 4242:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516
____kasan_slab_free+0x144/0x1c0 mm/kasan/common.c:236
__kasan_slab_free+0x18/0x28 mm/kasan/common.c:244
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1724 [inline]
slab_free_freelist_hook mm/slub.c:1750 [inline]
slab_free mm/slub.c:3661 [inline]
kmem_cache_free+0x2f0/0x588 mm/slub.c:3683
kfree_skbmem+0x10c/0x19c
__kfree_skb net/core/skbuff.c:871 [inline]
kfree_skb_reason+0x1ac/0x47c net/core/skbuff.c:893
kfree_skb include/linux/skbuff.h:1220 [inline]
__hci_req_sync+0x4fc/0x7ac net/bluetooth/hci_request.c:184
hci_req_sync+0xa4/0xd0 net/bluetooth/hci_request.c:206
hci_dev_cmd+0x330/0x90c net/bluetooth/hci_core.c:790
hci_sock_ioctl+0x4b8/0x82c net/bluetooth/hci_sock.c:1096
sock_do_ioctl+0x134/0x2dc net/socket.c:1204
sock_ioctl+0x4ec/0x858 net/socket.c:1321
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the object at ffff0000ed5e7780
which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 0 bytes inside of
240-byte region [ffff0000ed5e7780, ffff0000ed5e7870)

The buggy address belongs to the physical page:
page:00000000af3128bb refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12d5e7
flags: 0x5ffe00000000200(slab|node=0|zone=2|lastcpupid=0xfff)
raw: 05ffe00000000200 0000000000000000 dead000000000122 ffff0000c0870000
raw: 0000000000000000 00000000000c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff0000ed5e7680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff0000ed5e7700: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
>ffff0000ed5e7780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff0000ed5e7800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
ffff0000ed5e7880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
==================================================================
Bluetooth: hci4: command tx timeout
Bluetooth: hci3: command tx timeout
Bluetooth: hci0: command tx timeout
Bluetooth: hci1: command 0x0000 tx timeout
Bluetooth: hci2: command tx timeout
Bluetooth: hci0: command tx timeout
Bluetooth: hci2: command tx timeout
Bluetooth: hci1: command 0x0000 tx timeout
Bluetooth: hci0: command tx timeout
Bluetooth: hci1: command 0x0000 tx timeout
Bluetooth: hci2: command tx timeout


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