BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:102 [inline] BUG: KASAN: use-after-free in atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1779 [inline] BUG: KASAN: use-after-free in __mutex_trylock_fast kernel/locking/mutex.c:176 [inline] BUG: KASAN: use-after-free in mutex_lock+0x86/0x1b0 kernel/locking/mutex.c:295 Write of size 8 at addr ffff88810e773550 by task syz-executor346/312 CPU: 0 PID: 312 Comm: syz-executor346 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x71/0x200 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:420 kasan_report+0x122/0x150 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:102 [inline] atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1779 [inline] __mutex_trylock_fast kernel/locking/mutex.c:176 [inline] mutex_lock+0x86/0x1b0 kernel/locking/mutex.c:295 pppol2tp_release+0x178/0x2b0 net/l2tp/l2tp_ppp.c:441 __sock_release net/socket.c:652 [inline] sock_close+0xc9/0x220 net/socket.c:1390 __fput+0x1fd/0x8f0 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x1e1/0x250 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xb0d/0x29f0 kernel/exit.c:896 do_group_exit+0x21b/0x2e0 kernel/exit.c:1040 __do_sys_exit_group kernel/exit.c:1051 [inline] __se_sys_exit_group kernel/exit.c:1049 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1049 x64_sys_call+0x7b4/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fb07d090cc5 Code: Unable to access opcode bytes at 0x7fb07d090c9b. RSP: 002b:00007ffd36fc79b8 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fb07d090cc5 RDX: 00000000000000e7 RSI: ffffffffffffffd8 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000009 R10: 0000000000000009 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fb07d12a110 R14: 00007fb07d12c3a8 R15: 00007fb07d12c3c0 Allocated by task 312: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:380 [inline] __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:389 kasan_kmalloc include/linux/kasan.h:212 [inline] __do_kmalloc_node mm/slab_common.c:938 [inline] __kmalloc+0xb4/0x1e0 mm/slab_common.c:951 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] l2tp_session_create+0x38/0xbd0 net/l2tp/l2tp_core.c:1614 pppol2tp_connect+0xbf5/0x1640 net/l2tp/l2tp_ppp.c:771 __sys_connect_file net/socket.c:2001 [inline] __sys_connect+0x3da/0x460 net/socket.c:2018 __do_sys_connect net/socket.c:2028 [inline] __se_sys_connect net/socket.c:2025 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2025 x64_sys_call+0x88d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:43 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 312: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:242 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:250 kasan_slab_free include/linux/kasan.h:178 [inline] slab_free_hook mm/slub.c:1750 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776 slab_free mm/slub.c:3712 [inline] __kmem_cache_free+0xb7/0x1b0 mm/slub.c:3728 kfree+0x6f/0xf0 mm/slab_common.c:990 l2tp_session_free net/l2tp/l2tp_core.c:168 [inline] l2tp_session_put+0xaf/0x1a0 net/l2tp/l2tp_core.c:193 l2tp_session_delete+0x3df/0x4d0 net/l2tp/l2tp_core.c:1587 pppol2tp_release+0x169/0x2b0 net/l2tp/l2tp_ppp.c:438 __sock_release net/socket.c:652 [inline] sock_close+0xc9/0x220 net/socket.c:1390 __fput+0x1fd/0x8f0 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x1e1/0x250 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xb0d/0x29f0 kernel/exit.c:896 do_group_exit+0x21b/0x2e0 kernel/exit.c:1040 __do_sys_exit_group kernel/exit.c:1051 [inline] __se_sys_exit_group kernel/exit.c:1049 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1049 x64_sys_call+0x7b4/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 __call_rcu_common kernel/rcu/tree.c:2807 [inline] call_rcu+0xcf/0xf50 kernel/rcu/tree.c:2926 assoc_array_apply_edit+0x9fb/0xa50 lib/assoc_array.c:1396 __key_link+0xd6/0x120 security/keys/keyring.c:1376 __key_instantiate_and_link+0x24c/0x3d0 security/keys/key.c:460 key_instantiate_and_link+0x3a1/0x4e0 security/keys/key.c:538 keyring_alloc+0x70/0xb0 security/keys/keyring.c:529 look_up_user_keyrings+0x32d/0x630 security/keys/process_keys.c:106 init_root_keyring+0x12/0x14 security/keys/process_keys.c:962 do_one_initcall+0x1d6/0x580 init/main.c:1433 do_initcall_level+0x174/0x2df init/main.c:1506 do_initcalls+0x50/0x92 init/main.c:1522 do_basic_setup+0x92/0x99 init/main.c:1541 kernel_init_freeable+0x2d1/0x42d init/main.c:1761 kernel_init+0x1d/0x1c0 init/main.c:1649 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff88810e773400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 336 bytes inside of 512-byte region [ffff88810e773400, ffff88810e773600) The buggy address belongs to the physical page: page:ffffea000439dc00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88810e771800 pfn:0x10e770 head:ffffea000439dc00 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 0000000000000000 dead000000000001 ffff888100042f00 raw: ffff88810e771800 000000008010000f 00000001ffffffff 0000000000000000 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 1, tgid 1 (swapper/0), ts 2614244466, free_ts 2612523480 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2673 prep_new_page+0x1c/0x110 mm/page_alloc.c:2680 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4587 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5931 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3e0 mm/slub.c:2020 ___slab_alloc+0x70f/0xb70 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x204/0x2d0 mm/slub.c:3423 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc+0xa4/0x1e0 mm/slab_common.c:951 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] alloc_workqueue+0x15e/0x1320 kernel/workqueue.c:4339 fsverity_init_workqueue+0x4e/0x84 fs/verity/verify.c:397 fsverity_init+0x36/0x80 fs/verity/init.c:44 do_one_initcall+0x1d6/0x580 init/main.c:1433 do_initcall_level+0x174/0x2df init/main.c:1506 do_initcalls+0x50/0x92 init/main.c:1522 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1581 [inline] free_pcp_prepare mm/page_alloc.c:1655 [inline] free_unref_page_prepare+0x81b/0x820 mm/page_alloc.c:3622 free_unref_page+0x93/0x530 mm/page_alloc.c:3720 free_the_page mm/page_alloc.c:863 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:6021 free_pages+0x82/0x90 mm/page_alloc.c:6032 __stack_depot_save+0x45f/0x490 lib/stackdepot.c:506 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_set_track+0x60/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:334 kasan_slab_alloc include/linux/kasan.h:202 [inline] slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768 slab_alloc_node mm/slub.c:3382 [inline] slab_alloc mm/slub.c:3392 [inline] __kmem_cache_alloc_lru mm/slub.c:3399 [inline] kmem_cache_alloc_lru+0x104/0x280 mm/slub.c:3415 alloc_inode_sb include/linux/fs.h:3263 [inline] alloc_inode fs/inode.c:266 [inline] new_inode_pseudo+0x8f/0x1f0 fs/inode.c:1074 new_inode+0x28/0x1e0 fs/inode.c:1102 debugfs_get_inode fs/debugfs/inode.c:72 [inline] __debugfs_create_file+0x149/0x500 fs/debugfs/inode.c:432 debugfs_create_file+0x4a/0x60 fs/debugfs/inode.c:489 split_huge_pages_debugfs+0x25/0x29 mm/huge_memory.c:3327 do_one_initcall+0x1d6/0x580 init/main.c:1433 Memory state around the buggy address: ffff88810e773400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88810e773480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88810e773500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88810e773580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88810e773600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================