================================================================== BUG: KASAN: slab-use-after-free in put_ctx+0xb4/0x1d0 kernel/events/core.c:1394 BUG: KASAN: slab-use-after-free in put_ctx+0xb4/0x1d0 kernel/events/core.c:1394 Read of size 8 at addr ffff88807abdfd28 by task syz.3.460/8324 CPU: 0 UID: 0 PID: 8324 Comm: syz.3.460 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026 Call Trace: 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 put_ctx+0xb4/0x1d0 kernel/events/core.c:1394 __free_event+0x4f6/0x790 kernel/events/core.c:5817 put_event kernel/events/core.c:5936 [inline] perf_event_release_kernel+0x40e/0x4c0 kernel/events/core.c:6046 perf_release+0x38/0x50 kernel/events/core.c:6056 __fput+0x408/0xa40 fs/file_table.c:512 fput_close_sync+0x11f/0x240 fs/file_table.c:618 filp_close_sync+0x6e/0xa0 fs/open.c:1573 close_files fs/file.c:572 [inline] put_files_struct+0x230/0x3c0 fs/file.c:584 do_exit+0x6f0/0x2360 kernel/exit.c:977 __do_sys_exit kernel/exit.c:1090 [inline] __se_sys_exit kernel/exit.c:1088 [inline] __x64_sys_exit+0x40/0x40 kernel/exit.c:1088 x64_sys_call+0x18b4/0x18d0 arch/x86/include/generated/asm/syscalls_64.h:61 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: 0033:0x7f38d41a8f19 Code: Unable to access opcode bytes at 0x7f38d41a8eef. RSP: 002b:00007f38d4ff7fd8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c RAX: ffffffffffffffda RBX: 00007f38d4426090 RCX: 00007f38d41a8f19 RDX: 00007f38d4ff89c8 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f38d4237f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f38d4426128 R14: 00007f38d4426090 R15: 00007ffce1039d08 Allocated by task 8313: 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+0x31c/0x600 mm/slub.c:5680 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] alloc_perf_context kernel/events/core.c:5082 [inline] find_get_context+0xc7/0x860 kernel/events/core.c:5152 __do_sys_perf_event_open kernel/events/core.c:14200 [inline] __se_sys_perf_event_open+0xc40/0x1ee0 kernel/events/core.c:14031 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 8338: 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:2780 [inline] slab_free mm/slub.c:6630 [inline] kfree+0x1c5/0x650 mm/slub.c:6923 rcu_do_batch kernel/rcu/tree.c:2650 [inline] rcu_core+0x92e/0x1230 kernel/rcu/tree.c:2919 handle_softirqs+0x265/0x8d0 kernel/softirq.c:669 __do_softirq kernel/softirq.c:703 [inline] invoke_softirq kernel/softirq.c:542 [inline] __irq_exit_rcu+0xc6/0x220 kernel/softirq.c:786 irq_exit_rcu+0x9/0x30 kernel/softirq.c:809 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3287 [inline] call_rcu+0x86/0x300 kernel/rcu/tree.c:3395 perf_event_exit_task_context+0x68e/0x7c0 kernel/events/core.c:14819 perf_event_exit_task+0x232/0x3a0 kernel/events/core.c:14848 do_exit+0x69b/0x2360 kernel/exit.c:959 do_group_exit+0x22d/0x2f0 kernel/exit.c:1123 get_signal+0x136a/0x1430 kernel/signal.c:3113 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x10e/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 ffff88807abdfc00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 296 bytes inside of freed 512-byte region [ffff88807abdfc00, ffff88807abdfe00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807abdf800 pfn:0x7abdc head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88813ff28c80 ffffea00014a5110 ffffea000074ba10 raw: ffff88807abdf800 0000000000100008 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88813ff28c80 ffffea00014a5110 ffffea000074ba10 head: ffff88807abdf800 0000000000100008 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5277, tgid 5277 (S30dbus), ts 49489599498 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1856 prep_new_page mm/page_alloc.c:1864 [inline] get_page_from_freelist+0x220f/0x2280 mm/page_alloc.c:3935 __alloc_frozen_pages_noprof+0x1fe/0x410 mm/page_alloc.c:5444 alloc_slab_page mm/slub.c:3384 [inline] allocate_slab+0x7d/0x5e0 mm/slub.c:3499 new_slab mm/slub.c:3550 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7539 refill_sheaf mm/slub.c:2917 [inline] __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4811 alloc_from_pcs mm/slub.c:4887 [inline] slab_alloc_node mm/slub.c:5021 [inline] __do_kmalloc_node mm/slub.c:5530 [inline] __kmalloc_noprof+0x476/0x710 mm/slub.c:5556 _kmalloc_noprof include/linux/slab.h:995 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] tomoyo_init_log+0x1a6b/0x1f60 security/tomoyo/audit.c:273 tomoyo_supervisor+0x35f/0x1550 security/tomoyo/common.c:2232 tomoyo_audit_path_number_log security/tomoyo/file.c:239 [inline] tomoyo_path_number_perm+0x463/0x5f0 security/tomoyo/file.c:739 security_file_ioctl+0xc3/0x2a0 security/security.c:2533 __do_sys_ioctl fs/ioctl.c:591 [inline] __se_sys_ioctl+0x47/0x170 fs/ioctl.c:583 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 page last free pid 5003 tgid 5003 ts 41185611989 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1403 [inline] __free_frozen_pages+0xc97/0xd90 mm/page_alloc.c:2954 __slab_free+0x269/0x2c0 mm/slub.c:5926 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:361 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4720 [inline] slab_alloc_node mm/slub.c:5033 [inline] kmem_cache_alloc_noprof+0x2b4/0x600 mm/slub.c:5047 lsm_file_alloc security/security.c:172 [inline] security_file_alloc+0x34/0x310 security/security.c:2428 init_file+0x90/0x2b0 fs/file_table.c:184 alloc_empty_file+0x74/0x1d0 fs/file_table.c:266 path_openat+0x96/0x20f0 fs/namei.c:5002 do_file_open+0x23e/0x4a0 fs/namei.c:5045 do_sys_openat2+0x115/0x200 fs/open.c:1442 do_sys_open fs/open.c:1448 [inline] __do_sys_openat fs/open.c:1464 [inline] __se_sys_openat fs/open.c:1459 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1459 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 Memory state around the buggy address: ffff88807abdfc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807abdfc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807abdfd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807abdfd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807abdfe00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================