audit: type=1400 audit(1595975975.229:8): avc: denied { execmem } for pid=6365 comm="syz-executor313" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 ================================================================== BUG: KASAN: stack-out-of-bounds in deref_stack_regs arch/x86/kernel/unwind_orc.c:311 [inline] BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x146f/0x17d0 arch/x86/kernel/unwind_orc.c:441 Read of size 8 at addr ffff8880974ef790 by task syz-executor313/6376 CPU: 0 PID: 6376 Comm: syz-executor313 Not tainted 4.14.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 deref_stack_regs arch/x86/kernel/unwind_orc.c:311 [inline] unwind_next_frame+0x146f/0x17d0 arch/x86/kernel/unwind_orc.c:441 perf_callchain_kernel+0x38c/0x520 arch/x86/events/core.c:2343 get_perf_callchain+0x2df/0x740 kernel/events/callchain.c:217 perf_callchain+0x147/0x190 kernel/events/callchain.c:190 perf_prepare_sample+0xd77/0x1380 kernel/events/core.c:6162 __perf_event_output kernel/events/core.c:6278 [inline] perf_event_output_forward+0xc9/0x1f0 kernel/events/core.c:6296 __perf_event_overflow+0x113/0x310 kernel/events/core.c:7541 perf_swevent_overflow kernel/events/core.c:7617 [inline] perf_swevent_event+0x299/0x460 kernel/events/core.c:7645 perf_tp_event+0x540/0x6e0 kernel/events/core.c:8079 perf_trace_run_bpf_submit+0x119/0x200 kernel/events/core.c:8049 perf_trace_lock+0x2d6/0x490 include/trace/events/lock.h:39 trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0x4df/0x870 kernel/locking/lockdep.c:4016 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_unlock_irqrestore+0x1b/0xe0 kernel/locking/spinlock.c:192 __debug_check_no_obj_freed lib/debugobjects.c:760 [inline] debug_check_no_obj_freed+0x2c0/0x674 lib/debugobjects.c:776 kmem_cache_free+0x156/0x2b0 mm/slab.c:3757 anon_vma_chain_free mm/rmap.c:134 [inline] unlink_anon_vmas+0x289/0x7e0 mm/rmap.c:401 free_pgtables+0x178/0x2b0 mm/memory.c:643 exit_mmap+0x280/0x4b0 mm/mmap.c:3057 __mmput kernel/fork.c:930 [inline] mmput kernel/fork.c:951 [inline] mmput+0xfa/0x420 kernel/fork.c:946 exit_mm kernel/exit.c:545 [inline] do_exit+0x948/0x27f0 kernel/exit.c:852 do_group_exit+0x100/0x2e0 kernel/exit.c:962 get_signal+0x38d/0x1ca0 kernel/signal.c:2423 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:814 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4468c9 RSP: 002b:00007f0ae7627db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00000000006dbc28 RCX: 00000000004468c9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc28 RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c R13: 00007ffd8fc7718f R14: 00007f0ae76289c0 R15: 0000000000000000 The buggy address belongs to the page: page:ffffea00025d3bc0 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0xfffe0000000000() raw: 00fffe0000000000 0000000000000000 0000000000000000 00000000ffffffff raw: 0000000000000000 0000000100000001 0000000000000000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880974ef680: 00 00 00 00 00 00 f1 f1 f1 f1 f1 f1 04 f2 00 f3 ffff8880974ef700: f3 f3 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 >ffff8880974ef780: 04 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff8880974ef800: 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 ffff8880974ef880: f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================