================================================================== BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:183 [inline] BUG: KASAN: use-after-free in membarrier_mm_sync_core_before_usermode include/linux/sched/mm.h:216 [inline] BUG: KASAN: use-after-free in finish_task_switch+0x590/0x5e8 kernel/sched/core.c:2720 Read of size 4 at addr ffff800073dd4980 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.16.0-rc1-00001-g3fffa6166965-dirty #13 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x388 arch/arm64/kernel/time.c:52 show_stack+0x20/0x30 arch/arm64/kernel/traps.c:151 __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xd0/0x120 lib/dump_stack.c:53 print_address_description+0x5c/0x2a8 mm/kasan/report.c:262 kasan_report_error mm/kasan/report.c:362 [inline] kasan_report+0x210/0x340 mm/kasan/report.c:420 __asan_report_load4_noabort+0x18/0x20 mm/kasan/report.c:440 __read_once_size include/linux/compiler.h:183 [inline] membarrier_mm_sync_core_before_usermode include/linux/sched/mm.h:216 [inline] finish_task_switch+0x590/0x5e8 kernel/sched/core.c:2720 context_switch kernel/sched/core.c:2860 [inline] __schedule+0x4f0/0x1558 kernel/sched/core.c:3435 schedule_idle+0x40/0x80 kernel/sched/core.c:3521 do_idle+0x114/0x2e0 kernel/sched/idle.c:269 cpu_startup_entry+0x24/0x28 kernel/sched/idle.c:351 secondary_start_kernel+0x290/0x318 arch/arm64/kernel/smp.c:283 Allocated by task 12964: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xd0/0x180 mm/kasan/kasan.c:552 kasan_slab_alloc+0x14/0x20 mm/kasan/kasan.c:489 slab_post_alloc_hook mm/slab.h:443 [inline] slab_alloc_node mm/slub.c:2725 [inline] slab_alloc mm/slub.c:2733 [inline] kmem_cache_alloc+0x150/0x240 mm/slub.c:2738 dup_mm kernel/fork.c:1235 [inline] copy_mm kernel/fork.c:1298 [inline] copy_process.isra.7.part.8+0x1a10/0x5018 kernel/fork.c:1804 copy_process kernel/fork.c:1617 [inline] _do_fork+0x178/0x998 kernel/fork.c:2098 SYSC_clone kernel/fork.c:2205 [inline] SyS_clone+0x48/0x60 kernel/fork.c:2183 el0_svc_naked+0x30/0x34 Freed by task 10882: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] __kasan_slab_free+0x114/0x220 mm/kasan/kasan.c:520 kasan_slab_free+0x10/0x18 mm/kasan/kasan.c:527 slab_free_hook mm/slub.c:1393 [inline] slab_free_freelist_hook mm/slub.c:1414 [inline] slab_free mm/slub.c:2968 [inline] kmem_cache_free+0x88/0x270 mm/slub.c:2990 __mmdrop+0x164/0x248 kernel/fork.c:604 mmdrop+0x50/0x60 kernel/fork.c:615 __mmput kernel/fork.c:981 [inline] mmput+0x270/0x338 kernel/fork.c:992 exit_mm kernel/exit.c:544 [inline] do_exit+0x640/0x2100 kernel/exit.c:852 do_group_exit+0xdc/0x260 kernel/exit.c:968 get_signal+0x2ec/0xfc8 kernel/signal.c:2469 do_signal+0x270/0x4f8 arch/arm64/kernel/signal.c:869 do_notify_resume+0x150/0x1c0 arch/arm64/kernel/signal.c:927 work_pending+0x8/0x14 The buggy address belongs to the object at ffff800073dd4600 which belongs to the cache mm_struct of size 1104 The buggy address is located 896 bytes inside of 1104-byte region [ffff800073dd4600, ffff800073dd4a50) The buggy address belongs to the page: page:ffff7e0001cf7400 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 flags: 0x4fffc00000008100(slab|head) raw: 4fffc00000008100 0000000000000000 0000000000000000 0000000180190019 raw: ffff7e0001d2b000 0000000700000007 ffff800075803000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff800073dd4880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff800073dd4900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff800073dd4980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff800073dd4a00: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc ffff800073dd4a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================