==================================================================
BUG: KASAN: slab-use-after-free in rt_mutex_owner include/linux/rtmutex.h:52 [inline]
BUG: KASAN: slab-use-after-free in rt_mutex_slowtrylock kernel/locking/rtmutex.c:1397 [inline]
BUG: KASAN: slab-use-after-free in rt_mutex_try_acquire kernel/locking/rtmutex.c:325 [inline]
BUG: KASAN: slab-use-after-free in __rt_mutex_lock kernel/locking/rtmutex.c:1839 [inline]
BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/rtmutex_api.c:562 [inline]
BUG: KASAN: slab-use-after-free in mutex_lock_interruptible_nested+0xc9/0x1d0 kernel/locking/rtmutex_api.c:594
Read of size 8 at addr ffff888072c60850 by task syz.1.1533/10437

CPU: 0 UID: 0 PID: 10437 Comm: syz.1.1533 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Comput
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 rt_mutex_owner include/linux/rtmutex.h:52 [inline]
 rt_mutex_slowtrylock kernel/locking/rtmutex.c:1397 [inline]
 rt_mutex_try_acquire kernel/locking/rtmutex.c:325 [inline]
 __rt_mutex_lock kernel/locking/rtmutex.c:1839 [inline]
 __mutex_lock_common kernel/locking/rtmutex_api.c:562 [inline]
 mutex_lock_interruptible_nested+0xc9/0x1d0 kernel/locking/rtmutex_api.c:594
 ep_open+0x4e/0x270 drivers/usb/gadget/legacy/inode.c:832
 do_dentry_open+0x849/0x1420 fs/open.c:996
 vfs_open+0x3b/0x350 fs/open.c:1101
 do_open fs/namei.c:4866 [inline]
 path_openat+0x1448/0x1d60 fs/namei.c:5029
 do_file_open+0x23e/0x4a0 fs/namei.c:5058
 do_sys_openat2+0x115/0x200 fs/open.c:1417
 do_sys_open fs/open.c:1423 [inline]
 __do_sys_openat fs/open.c:1439 [inline]
 __se_sys_openat fs/open.c:1434 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1434
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f88926fe559
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8890935028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f8892986090 RCX: 00007f88926fe559
RDX: 0000000000000002 RSI: 0000200000000600 RDI: ffffffffffffff9c
RBP: 00007f88927958b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8892986128 R14: 00007f8892986090 R15: 00007ffc63c05ed8
 </TASK>

Allocated by task 10434:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:409 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x3d5/0x680 mm/slub.c:5563
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 activate_ep_files drivers/usb/gadget/legacy/inode.c:1611 [inline]
 gadgetfs_bind+0x27a/0xae0 drivers/usb/gadget/legacy/inode.c:1702
 gadget_bind_driver+0x2ca/0x9e0 drivers/usb/gadget/udc/core.c:1662
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:706
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
 __driver_attach+0x339/0x600 drivers/base/dd.c:1292
 bus_for_each_dev+0x23e/0x2c0 drivers/base/bus.c:383
 bus_add_driver+0x348/0x670 drivers/base/bus.c:763
 driver_register+0x23a/0x320 drivers/base/driver.c:174
 usb_gadget_register_driver_owner+0xf9/0x270 drivers/usb/gadget/udc/core.c:1752
 dev_config+0xe4e/0x12c0 drivers/usb/gadget/legacy/inode.c:1893
 vfs_write+0x29f/0xbb0 fs/read_write.c:685
 ksys_write+0x156/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 10434:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:264 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2748 [inline]
 slab_free mm/slub.c:6509 [inline]
 kfree+0x1c5/0x6d0 mm/slub.c:6802
 destroy_ep_files+0x29f/0x330 drivers/usb/gadget/legacy/inode.c:1592
 gadgetfs_unbind+0x112/0x2c0 drivers/usb/gadget/legacy/inode.c:1665
 gadget_unbind_driver+0x1cb/0x410 drivers/usb/gadget/udc/core.c:1724
 device_remove drivers/base/dd.c:616 [inline]
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x48b/0x880 drivers/base/dd.c:1372
 driver_detach+0x1f3/0x2d0 drivers/base/dd.c:1435
 bus_remove_driver+0x229/0x320 drivers/base/bus.c:832
 usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1784
 dev_release+0x86/0x210 drivers/usb/gadget/legacy/inode.c:1207
 __fput+0x41f/0xa80 fs/file_table.c:512
 task_work_run+0x1d9/0x270 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:70 [inline]
 exit_to_user_mode_loop+0x204/0x770 kernel/entry/common.c:101
 __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:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
 do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888072c60800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 80 bytes inside of
 freed 512-byte region [ffff888072c60800, ffff888072c60a00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x72c60
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88813ffbec80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 0080000000000040 ffff88813ffbec80 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 0080000000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9708, tgid 9704 (syz.5.1332), ts 364863566948
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0x2591/0x2600 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x230/0x5c0 mm/page_alloc.c:5436
 alloc_slab_page mm/slub.c:3347 [inline]
 allocate_slab+0x7d/0x620 mm/slub.c:3462
 new_slab mm/slub.c:3513 [inline]
 refill_objects+0x2d8/0x350 mm/slub.c:7418
 refill_sheaf mm/slub.c:2885 [inline]
 __pcs_replace_empty_main+0x339/0x690 mm/slub.c:4774
 alloc_from_pcs mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:4984 [inline]
 __kmalloc_cache_noprof+0x46f/0x680 mm/slub.c:5559
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 j1939_session_new+0xa2/0x5d0 net/can/j1939/transport.c:1523
 j1939_tp_send+0x391/0x8f0 net/can/j1939/transport.c:2061
 j1939_sk_send_loop net/can/j1939/socket.c:1172 [inline]
 j1939_sk_sendmsg+0xb58/0x1360 net/can/j1939/socket.c:1295
 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800
 __sock_sendmsg net/socket.c:815 [inline]
 ____sys_sendmsg+0x565/0x870 net/socket.c:2713
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2767
 __sys_sendmmsg+0x279/0x4d0 net/socket.c:2856
 __do_sys_sendmmsg net/socket.c:2883 [inline]
 __se_sys_sendmmsg net/socket.c:2880 [inline]
 __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2880
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
page last free pid 9674 tgid 9672 ts 363873453272 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0xf8e/0x1070 mm/page_alloc.c:2962
 __folio_put+0x30f/0x3c0 mm/folio.c:106
 folio_put include/linux/mm.h:2160 [inline]
 put_page include/linux/mm.h:2229 [inline]
 put_netmem include/net/netmem.h:394 [inline]
 skb_page_unref include/linux/skbuff_ref.h:43 [inline]
 __skb_frag_unref include/linux/skbuff_ref.h:56 [inline]
 skb_release_data+0x55f/0xa80 net/core/skbuff.c:1116
 skb_release_all net/core/skbuff.c:1197 [inline]
 __kfree_skb+0x5d/0x210 net/core/skbuff.c:1211
 tcp_write_queue_purge+0x138/0x360 net/ipv4/tcp.c:3353
 tcp_v4_destroy_sock+0x277/0x570 net/ipv4/tcp_ipv4.c:2440
 inet_csk_destroy_sock+0x165/0x340 net/ipv4/inet_connection_sock.c:1282
 __tcp_close+0xb1b/0xe90 net/ipv4/tcp.c:3300
 tcp_close+0x28/0x110 net/ipv4/tcp.c:3312
 inet_release+0x143/0x190 net/ipv4/af_inet.c:442
 __sock_release+0xa0/0x1f0 net/socket.c:735
 sock_close+0x1c/0x30 net/socket.c:1526
 __fput+0x41f/0xa80 fs/file_table.c:512
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 get_signal+0x1182/0x12c0 kernel/signal.c:2884
 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337

Memory state around the buggy address:
 ffff888072c60700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888072c60780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888072c60800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff888072c60880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888072c60900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================