================================================================== BUG: KASAN: use-after-free in task_work_run+0x1b0/0x270 kernel/task_work.c:178 Read of size 8 at addr ffff888011a8e358 by task syz-executor.3/5607 CPU: 1 PID: 5607 Comm: syz-executor.3 Not tainted 6.1.0-rc2-syzkaller-00212-g8ec95b94716a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15e/0x45d mm/kasan/report.c:395 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495 task_work_run+0x1b0/0x270 kernel/task_work.c:178 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xb35/0x2a20 kernel/exit.c:820 do_group_exit+0xd0/0x2a0 kernel/exit.c:950 get_signal+0x21a1/0x2430 kernel/signal.c:2858 arch_do_signal_or_restart+0x82/0x2300 arch/x86/kernel/signal.c:869 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:296 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f000248b5a9 Code: Unable to access opcode bytes at 0x7f000248b57f. RSP: 002b:00007f000316b168 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: 0000000000000003 RBX: 00007f00025abf80 RCX: 00007f000248b5a9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0 RBP: 00007f00024e67b0 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc593e392f R14: 00007f000316b300 R15: 0000000000022000 Allocated by task 5607: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x7e/0x80 mm/kasan/common.c:325 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:737 [inline] slab_alloc_node mm/slub.c:3398 [inline] kmem_cache_alloc_node+0x2fc/0x400 mm/slub.c:3443 perf_event_alloc.part.0+0x69/0x3bc0 kernel/events/core.c:11625 perf_event_alloc kernel/events/core.c:12174 [inline] __do_sys_perf_event_open+0x4ae/0x32d0 kernel/events/core.c:12272 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 5612: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2a/0x40 mm/kasan/generic.c:511 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] kmem_cache_free+0xea/0x5b0 mm/slub.c:3683 rcu_do_batch kernel/rcu/tree.c:2250 [inline] rcu_core+0x81f/0x1980 kernel/rcu/tree.c:2510 __do_softirq+0x1f7/0xad8 kernel/softirq.c:571 Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 call_rcu+0x99/0x820 kernel/rcu/tree.c:2798 put_event kernel/events/core.c:5095 [inline] perf_event_release_kernel+0x6f2/0x940 kernel/events/core.c:5210 perf_release+0x33/0x40 kernel/events/core.c:5220 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0x16b/0x270 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xb35/0x2a20 kernel/exit.c:820 do_group_exit+0xd0/0x2a0 kernel/exit.c:950 get_signal+0x21a1/0x2430 kernel/signal.c:2858 arch_do_signal_or_restart+0x82/0x2300 arch/x86/kernel/signal.c:869 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:296 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 task_work_add+0x7b/0x2c0 kernel/task_work.c:48 event_sched_out+0xe35/0x1190 kernel/events/core.c:2294 group_sched_out.part.0+0x116/0x470 kernel/events/core.c:2326 group_sched_out kernel/events/core.c:2321 [inline] ctx_sched_out+0x900/0xc70 kernel/events/core.c:3288 task_ctx_sched_out kernel/events/core.c:2663 [inline] ctx_resched+0x192/0x3c0 kernel/events/core.c:2710 __perf_install_in_context+0x28e/0x9c0 kernel/events/core.c:2792 remote_function kernel/events/core.c:92 [inline] remote_function+0x11e/0x1a0 kernel/events/core.c:72 __flush_smp_call_function_queue+0x205/0x9a0 kernel/smp.c:630 __sysvec_call_function_single+0xca/0x4d0 arch/x86/kernel/smp.c:248 sysvec_call_function_single+0x8e/0xc0 arch/x86/kernel/smp.c:243 asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:657 The buggy address belongs to the object at ffff888011a8df00 which belongs to the cache perf_event of size 1392 The buggy address is located 1112 bytes inside of 1392-byte region [ffff888011a8df00, ffff888011a8e470) The buggy address belongs to the physical page: page:ffffea000046a200 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888011a8c150 pfn:0x11a88 head:ffffea000046a200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff8880118c23c0 raw: ffff888011a8c150 000000008015000b 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x0(), pid 1, tgid 1 (swapper/0), ts 1842271713, free_ts 0 create_dummy_stack mm/page_owner.c:67 [inline] register_early_stack+0x65/0xa4 mm/page_owner.c:83 init_page_owner+0x56/0x632 mm/page_owner.c:93 invoke_init_callbacks mm/page_ext.c:126 [inline] page_ext_init+0x4be/0x4d1 mm/page_ext.c:518 kernel_init_freeable+0x4c4/0x788 init/main.c:1629 page_owner free stack trace missing Memory state around the buggy address: ffff888011a8e200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888011a8e280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888011a8e300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888011a8e380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888011a8e400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ==================================================================