================================================================== BUG: KASAN: use-after-free in is_idle_task include/linux/sched.h:1558 [inline] BUG: KASAN: use-after-free in wake_up_if_idle+0x266/0x2c0 kernel/sched/core.c:1852 Read of size 4 at addr ffff888051b1c324 by task syz-executor.0/24358 CPU: 0 PID: 24358 Comm: syz-executor.0 Not tainted 5.0.0+ #21 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 is_idle_task include/linux/sched.h:1558 [inline] wake_up_if_idle+0x266/0x2c0 kernel/sched/core.c:1852 wake_up_all_idle_cpus+0x6f/0xc0 kernel/smp.c:751 cpuidle_latency_notify+0xe/0x20 drivers/cpuidle/cpuidle.c:695 notifier_call_chain+0xc7/0x240 kernel/notifier.c:93 __blocking_notifier_call_chain kernel/notifier.c:317 [inline] __blocking_notifier_call_chain kernel/notifier.c:304 [inline] blocking_notifier_call_chain kernel/notifier.c:328 [inline] blocking_notifier_call_chain+0x94/0xb0 kernel/notifier.c:325 pm_qos_update_target+0x35d/0xa40 kernel/power/qos.c:305 pm_qos_add_request+0x20b/0x510 kernel/power/qos.c:449 snd_pcm_hw_params+0x16e9/0x1c20 sound/core/pcm_native.c:730 snd_pcm_kernel_ioctl+0xc3/0x1f0 sound/core/pcm_native.c:3029 snd_pcm_oss_change_params_locked+0x1b83/0x3750 sound/core/oss/pcm_oss.c:993 snd_pcm_oss_change_params+0x7b/0xd0 sound/core/oss/pcm_oss.c:1101 snd_pcm_oss_make_ready+0xbe/0x170 sound/core/oss/pcm_oss.c:1160 snd_pcm_oss_sync.isra.0+0x1c4/0x7e0 sound/core/oss/pcm_oss.c:1721 snd_pcm_oss_release+0x214/0x290 sound/core/oss/pcm_oss.c:2559 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458079 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f67e286ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffea RBX: 0000000000000004 RCX: 0000000000458079 RDX: 0000000000004000 RSI: 0000000020000140 RDI: ffffffffffffff9c RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f67e286b6d4 R13: 00000000004c3fb1 R14: 00000000004d73d8 R15: 00000000ffffffff Allocated by task 24361: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505 slab_post_alloc_hook mm/slab.h:436 [inline] slab_alloc_node mm/slab.c:3335 [inline] kmem_cache_alloc_node+0x131/0x710 mm/slab.c:3645 alloc_task_struct_node kernel/fork.c:157 [inline] dup_task_struct kernel/fork.c:844 [inline] copy_process.part.0+0x1d08/0x7980 kernel/fork.c:1752 copy_process kernel/fork.c:1709 [inline] _do_fork+0x257/0xfd0 kernel/fork.c:2226 __do_sys_clone kernel/fork.c:2333 [inline] __se_sys_clone kernel/fork.c:2327 [inline] __x64_sys_clone+0xbf/0x150 kernel/fork.c:2327 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 24364: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3764 free_task_struct kernel/fork.c:162 [inline] free_task+0xdd/0x120 kernel/fork.c:457 __put_task_struct+0x1fd/0x4e0 kernel/fork.c:730 put_task_struct include/linux/sched/task.h:98 [inline] finish_task_switch+0x52c/0x780 kernel/sched/core.c:2761 context_switch kernel/sched/core.c:2880 [inline] __schedule+0x81f/0x1cc0 kernel/sched/core.c:3518 preempt_schedule_common+0x4f/0xe0 kernel/sched/core.c:3642 preempt_schedule+0x4b/0x60 kernel/sched/core.c:3668 ___preempt_schedule+0x16/0x18 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0xbd/0xe0 kernel/locking/spinlock.c:184 spin_unlock_irqrestore include/linux/spinlock.h:384 [inline] release_pages+0x107b/0x1940 mm/swap.c:791 free_pages_and_swap_cache+0x2a0/0x3d0 mm/swap_state.c:295 tlb_flush_mmu_free+0x4e/0x120 mm/mmu_gather.c:74 tlb_flush_mmu+0x5a/0x520 mm/mmu_gather.c:83 arch_tlb_finish_mmu+0x3f/0x370 mm/mmu_gather.c:100 tlb_finish_mmu+0x9e/0x100 mm/mmu_gather.c:259 exit_mmap+0x2e2/0x530 mm/mmap.c:3140 __mmput kernel/fork.c:1046 [inline] mmput+0x15f/0x4c0 kernel/fork.c:1067 exit_mm kernel/exit.c:546 [inline] do_exit+0x816/0x2fa0 kernel/exit.c:863 do_group_exit+0x135/0x370 kernel/exit.c:980 __do_sys_exit_group kernel/exit.c:991 [inline] __se_sys_exit_group kernel/exit.c:989 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:989 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888051b1c300 which belongs to the cache task_struct of size 6080 The buggy address is located 36 bytes inside of 6080-byte region [ffff888051b1c300, ffff888051b1dac0) The buggy address belongs to the page: page:ffffea000146c700 count:1 mapcount:0 mapping:ffff88821bc407c0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0000db7d88 ffffea00013da588 ffff88821bc407c0 raw: 0000000000000000 ffff888051b1c300 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888051b1c200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888051b1c280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888051b1c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888051b1c380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888051b1c400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================