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Date: Thu, 25 Apr 2024 21:17:25 -0700
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Subject: [syzbot] [bluetooth?] KASAN: slab-use-after-free Read in hci_disconnect
From: syzbot <syzbot+9c830a0d0db9045210be@syzkaller.appspotmail.com>
To: johan.hedberg@gmail.com, linux-bluetooth@vger.kernel.org, 
	linux-kernel@vger.kernel.org, luiz.dentz@gmail.com, marcel@holtmann.org, 
	syzkaller-bugs@googlegroups.com
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Hello,

syzbot found the following issue on:

HEAD commit:    e33c4963bf53 Merge tag 'nfsd-6.9-5' of git://git.kernel.or..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16b9f237180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=98d5a8e00ed1044a
dashboard link: https://syzkaller.appspot.com/bug?extid=9c830a0d0db9045210be
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a58a1f6fe740/disk-e33c4963.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7cc2c92009ca/vmlinux-e33c4963.xz
kernel image: https://storage.googleapis.com/syzbot-assets/309e28d47292/bzImage-e33c4963.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9c830a0d0db9045210be@syzkaller.appspotmail.com

Bluetooth: hci3: killing stalled connection 11:aa:aa:aa:aa:aa
==================================================================
BUG: KASAN: slab-use-after-free in hci_disconnect+0x208/0x2d0 net/bluetooth/hci_conn.c:190
Read of size 1 at addr ffff88802a8a4039 by task kworker/u9:3/5104

CPU: 1 PID: 5104 Comm: kworker/u9:3 Not tainted 6.9.0-rc5-syzkaller-00053-ge33c4963bf53 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: hci3 hci_tx_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 hci_disconnect+0x208/0x2d0 net/bluetooth/hci_conn.c:190
 hci_link_tx_to net/bluetooth/hci_core.c:3495 [inline]
 __check_timeout+0x3a8/0x560 net/bluetooth/hci_core.c:3642
 hci_sched_le net/bluetooth/hci_core.c:3825 [inline]
 hci_tx_work+0x139b/0x1ef0 net/bluetooth/hci_core.c:3903
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3335
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
 kthread+0x2f2/0x390 kernel/kthread.c:388
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 5102:
 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:370 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 kmalloc_trace+0x1db/0x360 mm/slub.c:3997
 kmalloc include/linux/slab.h:628 [inline]
 kzalloc include/linux/slab.h:749 [inline]
 hci_conn_add+0xc7/0x13a0 net/bluetooth/hci_conn.c:914
 le_conn_complete_evt+0x303/0x12f0 net/bluetooth/hci_event.c:5771
 hci_le_conn_complete_evt+0x18c/0x420 net/bluetooth/hci_event.c:5923
 hci_event_func net/bluetooth/hci_event.c:7539 [inline]
 hci_event_packet+0xa55/0x1540 net/bluetooth/hci_event.c:7594
 hci_rx_work+0x3e8/0xca0 net/bluetooth/hci_core.c:4171
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3335
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
 kthread+0x2f2/0x390 kernel/kthread.c:388
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 5102:
 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:579
 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2106 [inline]
 slab_free mm/slub.c:4280 [inline]
 kfree+0x153/0x3a0 mm/slub.c:4390
 device_release+0x9b/0x1c0
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x231/0x480 lib/kobject.c:737
 hci_conn_cleanup net/bluetooth/hci_conn.c:176 [inline]
 hci_conn_del+0x900/0xc80 net/bluetooth/hci_conn.c:1126
 hci_abort_conn_sync+0x583/0xde0 net/bluetooth/hci_sync.c:5567
 hci_cmd_sync_work+0x22d/0x400 net/bluetooth/hci_sync.c:310
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3335
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
 kthread+0x2f2/0x390 kernel/kthread.c:388
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

The buggy address belongs to the object at ffff88802a8a4000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 57 bytes inside of
 freed 8192-byte region [ffff88802a8a4000, ffff88802a8a6000)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a8a0
head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
ksm flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000840 ffff888015042280 ffffea0000c0c200 dead000000000003
raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000
head: 00fff80000000840 ffff888015042280 ffffea0000c0c200 dead000000000003
head: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000
head: 00fff80000000003 ffffea0000aa2801 ffffea0000aa2848 00000000ffffffff
head: 0000000800000000 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid -1057826110 (swapper/0), ts 1, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317
 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 alloc_slab_page+0x5f/0x160 mm/slub.c:2175
 allocate_slab mm/slub.c:2338 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2391
 ___slab_alloc+0xc73/0x1260 mm/slub.c:3525
 __slab_alloc mm/slub.c:3610 [inline]
 __slab_alloc_node mm/slub.c:3663 [inline]
 slab_alloc_node mm/slub.c:3835 [inline]
 kmalloc_trace+0x269/0x360 mm/slub.c:3992
 kmalloc include/linux/slab.h:628 [inline]
 kzalloc include/linux/slab.h:749 [inline]
 ipv4_sysctl_init_net+0x1c0/0x270 net/ipv4/sysctl_net_ipv4.c:1540
 ops_init+0x354/0x610 net/core/net_namespace.c:136
 __register_pernet_operations net/core/net_namespace.c:1243 [inline]
 register_pernet_operations+0x2cb/0x660 net/core/net_namespace.c:1312
 register_pernet_subsys+0x28/0x40 net/core/net_namespace.c:1353
 sysctl_ipv4_init+0x40/0x80 net/ipv4/sysctl_net_ipv4.c:1578
 do_one_initcall+0x24a/0x880 init/main.c:1245
 do_initcall_level+0x157/0x210 init/main.c:1307
 do_initcalls+0x3f/0x80 init/main.c:1323
 kernel_init_freeable+0x435/0x5d0 init/main.c:1555
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88802a8a3f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802a8a3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802a8a4000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88802a8a4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a8a4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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