================================================================== BUG: KASAN: stack-out-of-bounds in __wake_up_common+0x6db/0x740 kernel/sched/wait.c:83 Read of size 8 at addr ffff8801bb4af648 by task syz-executor1/15907 kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access CPU: 1 PID: 15907 Comm: syz-executor1 Not tainted 4.18.0-rc3+ #48 general protection fault: 0000 [#1] SMP KASAN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 CPU: 0 PID: 1102416563 Comm: syz-exec Not tainted 4.18.0-rc3+ #48 Call Trace: Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:task_css include/linux/cgroup.h:477 [inline] RIP: 0010:task_ca kernel/sched/cpuacct.c:43 [inline] RIP: 0010:cpuacct_account_field+0x13c/0x3b0 kernel/sched/cpuacct.c:365 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113 Code: da 45 08 00 85 c0 74 print_address_description+0x6c/0x20b mm/kasan/report.c:256 0d 80 3d f1 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 1e 3c __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 08 00 __wake_up_common+0x6db/0x740 kernel/sched/wait.c:83 0f 84 79 01 00 00 48 b8 00 __wake_up_common_lock+0x1c2/0x330 kernel/sched/wait.c:119 00 00 00 00 __wake_up_sync_key+0x19/0x20 kernel/sched/wait.c:197 fc ff pipe_write+0x9d2/0xeb0 fs/pipe.c:477 df 49 call_write_iter include/linux/fs.h:1793 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x6c6/0x9f0 fs/read_write.c:487 8d 7d 10 48 89 fa 48 c1 ea vfs_write+0x1f8/0x560 fs/read_write.c:549 03 ksys_write+0x101/0x260 fs/read_write.c:598 <80> 3c 02 00 0f __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 85 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 49 02 00 00 4d 8b 65 10 49 81 fc entry_SYSCALL_64_after_hwframe+0x49/0xbe 80 RIP: 0033:0x40fbc1 a4 Code: f7 88 75 0f 14 RSP: 0018:ffff8801dae078e8 EFLAGS: 00010002 b8 RAX: dffffc0000000000 RBX: dffffc0000000000 RCX: ffffffff815d8e26 RDX: 000000000836b158 RSI: 0000000000000008 RDI: 0000000041b58ac3 01 RBP: ffff8801dae07978 R08: 0000000000000000 R09: 0000000000000000 00 R10: ffff8801dae07950 R11: ffffffff88fa1263 R12: ffff8801b939a300 R13: 0000000041b58ab3 R14: 1ffff1003b5c0f1e R15: 00000000000f4240 00 FS: 00007f4567bc4700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 00 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe134222000 CR3: 0000000008e6a000 CR4: 00000000001406f0 0f DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000 05 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: 48 3d 01 f0 ff cgroup_account_cputime_field include/linux/cgroup.h:739 [inline] task_group_account_field kernel/sched/cputime.c:108 [inline] account_system_index_time+0x1dc/0x5c0 kernel/sched/cputime.c:171 ff 0f 83 f4 19 00 00 account_system_time+0x7f/0xb0 kernel/sched/cputime.c:199 c3 account_process_tick+0x76/0x240 kernel/sched/cputime.c:498 48 update_process_times+0x21/0x70 kernel/time/timer.c:1634 83 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164 ec tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274 08 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x3eb/0x10c0 kernel/time/hrtimer.c:1460 e8 ca fc ff ff 48 89 04 24 b8 01 00 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518 00 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline] smp_apic_timer_interrupt+0x165/0x730 arch/x86/kernel/apic/apic.c:1050 00 0f 05 <48> 8b 3c apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863 24 48 Modules linked in: 89 c2 Dumping ftrace buffer: e8 --------------------------------- 13 syz-exec-8219 0...2 65067929us : 0: }D fd syz-exec-8219 0...2 65067935us : 0: }D ff syz-exec-8219 0...2 65067939us : 0: }D ff syz-exec-8219 0...2 65067941us : 0: }D 48 syz-exec-8219 0...2 65067944us : 0: }D 89 syz-exec-8219 0...2 65067946us : 0: }D d0 syz-exec-8219 0...2 65067950us : 0: }D 48 syz-exec-8219 0...2 65067952us : 0: }D 83 syz-exec-8219 0...2 65067954us : 0: }D c4 syz-exec-8219 0...2 65067957us : 0: }D 08 syz-exec-8219 0...2 65067960us : 0: }D 48 syz-exec-8219 0...2 65067962us : 0: }D 3d syz-exec-8219 0...2 65067965us : 0: }D 01 syz-exec-8219 0...2 65067968us : 0: }D syz-exec-8219 0...2 65067970us : 0: }D RSP: 002b:00007ffdb4ab7f30 EFLAGS: 00000293 syz-exec-8219 0...2 65067972us : 0: }D ORIG_RAX: 0000000000000001 syz-exec-8219 0...2 65067975us : 0: }D RAX: ffffffffffffffda RBX: 0000000000000038 RCX: 000000000040fbc1 syz-exec-8219 0...2 65067978us : 0: }D RDX: 0000000000000038 RSI: 00007ffdb4ab80d0 RDI: 0000000000000002 syz-exec-8219 0...2 65067980us : 0: }D RBP: 00007ffdb4ab80d0 R08: 00000000018f9940 R09: 0000000000000038 syz-exec-8219 0...2 65067982us : 0: }D R10: 0000000000000064 R11: 0000000000000293 R12: 0000000000000038 syz-exec-8219 0...2 65067985us : 0: }D R13: 0000000000000001 R14: 0000000000707f00 R15: 000000000072c680 syz-exec-8219 0...2 65067988us : 0: }D syz-exec-8219 0...2 65067990us : 0: }D Allocated by task 4372: syz-exec-8219 0...2 65067992us : 0: }D save_stack+0x43/0xd0 mm/kasan/kasan.c:448 syz-exec-8219 0...2 65067995us : 0: }D set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 syz-exec-8219 0...2 65067998us : 0: }D kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 syz-exec-8219 0...2 65068000us : 0: }D kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554 ep_ptable_queue_proc+0x14e/0x520 fs/eventpoll.c:1240 syz-exec-8219 0...2 65068002us : 0: }D poll_wait include/linux/poll.h:47 [inline] pipe_poll+0x94/0x340 fs/pipe.c:520 syz-exec-8219 0...2 65068006us : 0: }D vfs_poll include/linux/poll.h:86 [inline] ep_item_poll.isra.14+0x15c/0x400 fs/eventpoll.c:887 syz-exec-8219 0...2 65068008us : 0: }D ep_insert+0x6c1/0x1c20 fs/eventpoll.c:1459 syz-exec-8219 0...2 65068010us : 0: }D __do_sys_epoll_ctl fs/eventpoll.c:2113 [inline] __se_sys_epoll_ctl fs/eventpoll.c:1999 [inline] __x64_sys_epoll_ctl+0xf00/0x10a0 fs/eventpoll.c:1999 syz-exec-8219 0...2 65068013us : 0: }D do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 syz-exec-8219 0...2 65068016us : 0: }D entry_SYSCALL_64_after_hwframe+0x49/0xbe syz-exec-8219 0...2 65068018us : 0: }D syz-exec-8219 0...2 65068020us : 0: }D Freed by task 0: syz-exec-8219 0...2 65068023us : 0: }D (stack is not available) syz-exec-8219 0...2 65068026us : 0: }D syz-exec-8219 0...2 65068028us : 0: }D The buggy address belongs to the object at ffff8801bb4af618 which belongs to the cache eventpoll_pwq of size 72 syz-exec-8219 0...2 65068030us : 0: }D The buggy address is located 48 bytes inside of 72-byte region [ffff8801bb4af618, ffff8801bb4af660) syz-exec-8219 0...2 65068034us : 0: }D The buggy address belongs to the page: syz-exec-8219 0...2 65068036us : 0: }D page:ffffea0006ed2bc0 count:1 mapcount:0 mapping:ffff8801d4843e00 index:0x0 syz-exec-8219 0...2 65068039us : 0: }D syz-exec-8219 0...2 65068042us : 0: }D flags: 0x2fffc0000000100(slab) syz-exec-8219 0...2 65068046us : 0: }D raw: 02fffc0000000100 ffffea0006fbe208 ffffea00070b50c8 ffff8801d4843e00 syz-exec-8219 0...2 65068048us : 0: }D raw: 0000000000000000 ffff8801bb4af000 0000000100000027 0000000000000000 syz-exec-8219 0...2 65068051us : 0: }D page dumped because: kasan: bad access detected syz-exec-8219 0...2 65068054us : 0: }D syz-exec-8219 0...2 65068056us : 0: }D Memory state around the buggy address: syz-exec-8219 0...2 65068059us : 0: }D ffff8801bb4af500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 syz-exec-8219 0...2 65068061us : 0: }D ffff8801bb4af580: 00 f1 f1 f1 f1 00 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 syz-exec-8219 0...2 65068063us : 0: }D >ffff8801bb4af600: f2 f2 f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2 f8 f2 f2 syz-exec-8219 0...2 65068065us : 0: }D ^ syz-exec-8219 0...2 65068067us : 0: }D ffff8801bb4af680: f2 f2 f2 f2 f2 00 f2 f2 f2 00 00 00 00 00 00 00 syz-exec-8219 0...2 65068070us : 0: }D ffff8801bb4af700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 syz-exec-8219 0...2 65068072us : 0: }D ================================================================== syz-exec-8219 0...2 65068075us : 0: }D