==================================================================
BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x31/0x190 lib/list_debug.c:49
Read of size 8 at addr ffff888041438c30 by task syz.0.17/6563

CPU: 0 UID: 0 PID: 6563 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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
 __list_del_entry_valid_or_report+0x31/0x190 lib/list_debug.c:49
 __list_del_entry_valid include/linux/list.h:132 [inline]
 __list_del_entry include/linux/list.h:223 [inline]
 list_del_init include/linux/list.h:295 [inline]
 fuse_read_interrupt+0xdb/0x410 fs/fuse/dev.c:1388
 fuse_dev_do_read+0xa65/0x1280 fs/fuse/dev.c:1585
 fuse_dev_read+0x16a/0x200 fs/fuse/dev.c:1713
 io_iter_do_read io_uring/rw.c:835 [inline]
 __io_read+0x72f/0x1500 io_uring/rw.c:952
 io_read+0x4a/0x1c0 io_uring/rw.c:1031
 __io_issue_sqe+0x180/0x4b0 io_uring/io_uring.c:1387
 io_issue_sqe+0x165/0xf60 io_uring/io_uring.c:1410
 io_queue_sqe io_uring/io_uring.c:1636 [inline]
 io_req_task_submit+0xe6/0x180 io_uring/io_uring.c:1050
 io_poll_task_func+0x8d4/0xb20 io_uring/poll.c:-1
 io_handle_tw_list+0x258/0x540 io_uring/tw.c:72
 tctx_task_work_run+0x55/0x300 io_uring/tw.c:132
 tctx_task_work+0x3f/0x90 io_uring/tw.c:150
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 get_signal+0x11eb/0x1330 kernel/signal.c:2809
 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
 __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:238 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8224bdc819
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:00007f8224215028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: fffffffffffffffc RBX: 00007f8224e56090 RCX: 00007f8224bdc819
RDX: 0000000000040000 RSI: 0000200000000140 RDI: ffffffffffffff9c
RBP: 00007f8224c72c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000020 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8224e56128 R14: 00007f8224e56090 R15: 00007fff7755ce28
 </TASK>

Allocated by task 6563:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4577 [inline]
 slab_alloc_node mm/slub.c:4906 [inline]
 kmem_cache_alloc_noprof+0x33b/0x680 mm/slub.c:4913
 fuse_request_alloc fs/fuse/dev.c:50 [inline]
 fuse_get_req+0x6c3/0xac0 fs/fuse/dev.c:131
 fuse_chan_send+0x2d6/0x1aa0 fs/fuse/dev.c:816
 fuse_simple_request fs/fuse/fuse_i.h:1008 [inline]
 fuse_lookup_name+0x360/0x8d0 fs/fuse/dir.c:579
 fuse_lookup+0x204/0x500 fs/fuse/dir.c:626
 fuse_atomic_open+0x196/0x440 fs/fuse/dir.c:944
 atomic_open+0x14f/0x370 fs/namei.c:4364
 lookup_open fs/namei.c:4477 [inline]
 open_last_lookups fs/namei.c:4611 [inline]
 path_openat+0x1108/0x38a0 fs/namei.c:4855
 do_file_open+0x23e/0x4a0 fs/namei.c:4887
 do_sys_openat2+0x113/0x200 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6563:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2700 [inline]
 slab_free mm/slub.c:6258 [inline]
 kmem_cache_free+0x187/0x6c0 mm/slub.c:6385
 fuse_chan_send+0x150a/0x1aa0 fs/fuse/dev.c:833
 fuse_simple_request fs/fuse/fuse_i.h:1008 [inline]
 fuse_lookup_name+0x360/0x8d0 fs/fuse/dir.c:579
 fuse_lookup+0x204/0x500 fs/fuse/dir.c:626
 fuse_atomic_open+0x196/0x440 fs/fuse/dir.c:944
 atomic_open+0x14f/0x370 fs/namei.c:4364
 lookup_open fs/namei.c:4477 [inline]
 open_last_lookups fs/namei.c:4611 [inline]
 path_openat+0x1108/0x38a0 fs/namei.c:4855
 do_file_open+0x23e/0x4a0 fs/namei.c:4887
 do_sys_openat2+0x113/0x200 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888041438c18
 which belongs to the cache fuse_request of size 280
The buggy address is located 24 bytes inside of
 freed 280-byte region [ffff888041438c18, ffff888041438d30)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888041438d70 pfn:0x41438
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000240(workingset|head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000240 ffff888140e8b140 ffff88801e7ef588 ffff88801e7ef588
raw: ffff888041438d70 000000080017000a 00000000f5000000 0000000000000000
head: 0080000000000240 ffff888140e8b140 ffff88801e7ef588 ffff88801e7ef588
head: ffff888041438d70 000000080017000a 00000000f5000000 0000000000000000
head: 0080000000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff
head: ffff888041439a80 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6563, tgid 6561 (syz.0.17), ts 154371198329, free_ts 154308032836
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1853
 prep_new_page mm/page_alloc.c:1861 [inline]
 get_page_from_freelist+0x27d6/0x2850 mm/page_alloc.c:3941
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5249
 alloc_slab_page mm/slub.c:3289 [inline]
 allocate_slab+0x74/0x5e0 mm/slub.c:3404
 new_slab mm/slub.c:3447 [inline]
 refill_objects+0x33c/0x3d0 mm/slub.c:7263
 refill_sheaf mm/slub.c:2827 [inline]
 __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4659
 alloc_from_pcs mm/slub.c:4757 [inline]
 slab_alloc_node mm/slub.c:4891 [inline]
 kmem_cache_alloc_noprof+0x433/0x680 mm/slub.c:4913
 fuse_request_alloc fs/fuse/dev.c:50 [inline]
 fuse_get_req+0x6c3/0xac0 fs/fuse/dev.c:131
 fuse_chan_send+0x2d6/0x1aa0 fs/fuse/dev.c:816
 fuse_simple_request fs/fuse/fuse_i.h:1008 [inline]
 fuse_lookup_name+0x360/0x8d0 fs/fuse/dir.c:579
 fuse_lookup+0x204/0x500 fs/fuse/dir.c:626
 fuse_atomic_open+0x196/0x440 fs/fuse/dir.c:944
 atomic_open+0x14f/0x370 fs/namei.c:4364
 lookup_open fs/namei.c:4477 [inline]
 open_last_lookups fs/namei.c:4611 [inline]
 path_openat+0x1108/0x38a0 fs/namei.c:4855
 do_file_open+0x23e/0x4a0 fs/namei.c:4887
 do_sys_openat2+0x113/0x200 fs/open.c:1364
page last free pid 4978 tgid 4978 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1397 [inline]
 __free_frozen_pages+0x1075/0x11b0 mm/page_alloc.c:2938
 __slab_free+0x252/0x2a0 mm/slub.c:5620
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4577 [inline]
 slab_alloc_node mm/slub.c:4906 [inline]
 kmem_cache_alloc_node_noprof+0x22a/0x6e0 mm/slub.c:4958
 kmalloc_reserve net/core/skbuff.c:613 [inline]
 __alloc_skb+0x27d/0x7d0 net/core/skbuff.c:713
 netlink_sendmsg+0x5d4/0xb40 net/netlink/af_netlink.c:1869
 sock_sendmsg_nosec+0x112/0x150 net/socket.c:797
 __sock_sendmsg net/socket.c:812 [inline]
 ____sys_sendmsg+0x55c/0x870 net/socket.c:2716
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2770
 __sys_sendmsg net/socket.c:2802 [inline]
 __do_sys_sendmsg net/socket.c:2807 [inline]
 __se_sys_sendmsg net/socket.c:2805 [inline]
 __x64_sys_sendmsg+0x1c3/0x2a0 net/socket.c:2805
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888041438b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888041438b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888041438c00: fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888041438c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888041438d00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
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