syzbot

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BUG: KASAN: slab-use-after-free in rt_spin_lock+0x88/0x3e0 kernel/locking/spinlock_rt.c:56
Read of s[  258.262531][ T1193] Read of size 1 at addr ffff88805d10c250 by task kworker/1:2/1193

CPU: 1 UID: 0 PID: 1193 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: pm pm_runtime_work
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 __kasan_check_byte+0x2a/0x40 mm/kasan/common.c:580
 kasan_check_byte include/linux/kasan.h:401 [inline]
 lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5842
 rt_spin_lock+0x88/0x3e0 kernel/locking/spinlock_rt.c:56
 spin_lock include/linux/spinlock_rt.h:44 [inline]
 rpm_suspend+0x1223/0x1710 drivers/base/power/runtime.c:729
 pm_runtime_work+0x132/0x1b0 drivers/base/power/runtime.c:-1
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 1193:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __kmalloc_cache_noprof+0x1ef/0x6c0 mm/slub.c:5724
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 usb_alloc_dev+0x5d/0xd00 drivers/usb/core/usb.c:650
 hub_port_connect drivers/usb/core/hub.c:5469 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
 port_event drivers/usb/core/hub.c:5870 [inline]
 hub_event+0x2214/0x4a20 drivers/usb/core/hub.c:5952
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 9:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2514 [inline]
 slab_free mm/slub.c:6566 [inline]
 kfree+0x197/0x950 mm/slub.c:6773
 device_release+0x9c/0x1c0 drivers/base/core.c:-1
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x228/0x480 lib/kobject.c:737
 hub_port_connect drivers/usb/core/hub.c:5406 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
 port_event drivers/usb/core/hub.c:5870 [inline]
 hub_event+0x1cf5/0x4a20 drivers/usb/core/hub.c:5952
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Last potentially related work creation:
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559
 insert_work+0x3d/0x330 kernel/workqueue.c:2186
 __queue_work+0xd63/0x1010 kernel/workqueue.c:2341
 queue_work_on+0x181/0x270 kernel/workqueue.c:2392
 queue_work include/linux/workqueue.h:669 [inline]
 rpm_suspend+0xe5a/0x1710 drivers/base/power/runtime.c:685
 pm_suspend_timer_fn+0xe8/0x120 drivers/base/power/runtime.c:1028
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x552/0xd40 kernel/time/hrtimer.c:1841
 hrtimer_run_softirq+0x1a3/0x2e0 kernel/time/hrtimer.c:1858
 handle_softirqs+0x22f/0x710 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 run_ktimerd+0xcf/0x190 kernel/softirq.c:1138
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88805d10c000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 592 bytes inside of
 freed 2048-byte region [ffff88805d10c000, ffff88805d10c800)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5d108
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88813ffa7000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 0080000000000040 ffff88813ffa7000 dead000000000122 0000000000000000
head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 0080000000000003 ffffea0001744201 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 1193, tgid 1193 (kworker/1:2), ts 254855421914, free_ts 254851072185
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850
 prep_new_page mm/page_alloc.c:1858 [inline]
 get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3884
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:3030 [inline]
 allocate_slab+0x96/0x3a0 mm/slub.c:3203
 new_slab mm/slub.c:3257 [inline]
 ___slab_alloc+0xb12/0x1470 mm/slub.c:4627
 __slab_alloc+0xc6/0x1f0 mm/slub.c:4746
 __slab_alloc_node mm/slub.c:4822 [inline]
 slab_alloc_node mm/slub.c:5233 [inline]
 __do_kmalloc_node mm/slub.c:5602 [inline]
 __kmalloc_node_track_caller_noprof+0x2a8/0x7e0 mm/slub.c:5712
 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601
 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1383 [inline]
 mld_newpack+0x13c/0xc40 net/ipv6/mcast.c:1775
 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1886
 add_grec+0x1452/0x1740 net/ipv6/mcast.c:2025
 mld_send_cr net/ipv6/mcast.c:2148 [inline]
 mld_ifc_work+0x6ed/0xd60 net/ipv6/mcast.c:2693
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
page last free pid 5174 tgid 5174 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xfb6/0x1140 mm/page_alloc.c:2906
 discard_slab mm/slub.c:3301 [inline]
 __put_partials+0x149/0x170 mm/slub.c:3848
 __slab_free+0x29e/0x370 mm/slub.c:5882
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4946 [inline]
 slab_alloc_node mm/slub.c:5245 [inline]
 kmem_cache_alloc_node_noprof+0x23b/0x6e0 mm/slub.c:5297
 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6671
 sock_alloc_send_pskb+0x859/0x990 net/core/sock.c:2965
 unix_dgram_sendmsg+0x461/0x1850 net/unix/af_unix.c:2153
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:742
 __sys_sendto+0x3c7/0x520 net/socket.c:2244
 __do_sys_sendto net/socket.c:2251 [inline]
 __se_sys_sendto net/socket.c:2247 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2247
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805d10c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805d10c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805d10c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88805d10c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805d10c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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