================================================================== BUG: KASAN: use-after-free in hlist_move_list include/linux/list.h:729 [inline] BUG: KASAN: use-after-free in __collect_expired_timers kernel/time/timer.c:1339 [inline] BUG: KASAN: use-after-free in collect_expired_timers kernel/time/timer.c:1569 [inline] BUG: KASAN: use-after-free in __run_timers+0xa2e/0xb90 kernel/time/timer.c:1616 Write of size 8 at addr ffff8801ca473c48 by task syz-executor1/6090 CPU: 1 PID: 6090 Comm: syz-executor1 Not tainted 4.13.0-next-20170913+ #21 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x24e/0x340 mm/kasan/report.c:409 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report.c:435 hlist_move_list include/linux/list.h:729 [inline] __collect_expired_timers kernel/time/timer.c:1339 [inline] collect_expired_timers kernel/time/timer.c:1569 [inline] __run_timers+0xa2e/0xb90 kernel/time/timer.c:1616 run_timer_softirq+0x4c/0xb0 kernel/time/timer.c:1646 __do_softirq+0x2bb/0xbd0 kernel/softirq.c:284 invoke_softirq kernel/softirq.c:364 [inline] irq_exit+0x1d3/0x210 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:638 [inline] smp_apic_timer_interrupt+0x177/0x710 arch/x86/kernel/apic/apic.c:1048 apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:770 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:814 [inline] RIP: 0010:lock_is_held_type+0x18b/0x210 kernel/locking/lockdep.c:4042 RSP: 0000:ffff8801d538f650 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: dffffc0000000000 RBX: 0000000000000282 RCX: 0000000000000000 RDX: 1ffffffff0b59305 RSI: ffffffff85b380e0 RDI: 0000000000000282 RBP: ffff8801d538f670 R08: 0000160000000000 R09: 0000000000000000 R10: ffffffffffffffe8 R11: 0000000000000000 R12: ffff8801d4a5a1c0 R13: 0000000000000000 R14: 00000000000011c9 R15: dffffc0000000000 lock_is_held include/linux/lockdep.h:436 [inline] ___might_sleep+0x3d8/0x470 kernel/sched/core.c:5976 clear_huge_page+0x3e1/0x750 mm/memory.c:4553 __do_huge_pmd_anonymous_page mm/huge_memory.c:570 [inline] do_huge_pmd_anonymous_page+0x59c/0x1ba0 mm/huge_memory.c:728 create_huge_pmd mm/memory.c:3802 [inline] __handle_mm_fault+0x1827/0x39c0 mm/memory.c:4005 handle_mm_fault+0x334/0x8d0 mm/memory.c:4071 __do_page_fault+0x4f6/0xb60 arch/x86/mm/fault.c:1445 do_page_fault+0xee/0x720 arch/x86/mm/fault.c:1520 page_fault+0x22/0x30 arch/x86/entry/entry_64.S:1066 RIP: 0033:0x439351 RSP: 002b:0000000000a6f918 EFLAGS: 00010202 RAX: 0000000020571ff7 RBX: 0000000000000002 RCX: 000000000000002f RDX: 0000000000000009 RSI: 0000000000763478 RDI: 0000000020571ff7 RBP: 0000000000000009 R08: 00000000007180b0 R09: 0000001d0000e2bd R10: 0000000000a6f980 R11: 0000000000000000 R12: fffffffffffffffe R13: 00000000007180b0 R14: 0000000020571ff7 R15: 0000000000000010 Allocated by task 5527: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 __do_kmalloc_node mm/slab.c:3689 [inline] __kmalloc_node+0x47/0x70 mm/slab.c:3696 kmalloc_node include/linux/slab.h:535 [inline] kvmalloc_node+0x64/0xd0 mm/util.c:397 kvmalloc include/linux/mm.h:529 [inline] kvzalloc include/linux/mm.h:537 [inline] alloc_netdev_mqs+0x16e/0xed0 net/core/dev.c:8018 tun_set_iff drivers/net/tun.c:2022 [inline] __tun_chr_ioctl+0x12be/0x3d20 drivers/net/tun.c:2276 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2521 vfs_ioctl fs/ioctl.c:45 [inline] do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:685 SYSC_ioctl fs/ioctl.c:700 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed by task 5527: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kfree+0xca/0x250 mm/slab.c:3820 kvfree+0x36/0x60 mm/util.c:416 netdev_freemem net/core/dev.c:7970 [inline] free_netdev+0x2cf/0x360 net/core/dev.c:8132 tun_set_iff drivers/net/tun.c:2105 [inline] __tun_chr_ioctl+0x2cf6/0x3d20 drivers/net/tun.c:2276 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2521 vfs_ioctl fs/ioctl.c:45 [inline] do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:685 SYSC_ioctl fs/ioctl.c:700 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 entry_SYSCALL_64_fastpath+0x1f/0xbe The buggy address belongs to the object at ffff8801ca470840 which belongs to the cache kmalloc-16384 of size 16384 The buggy address is located 13320 bytes inside of 16384-byte region [ffff8801ca470840, ffff8801ca474840) The buggy address belongs to the page: page:ffffea0007291c00 count:1 mapcount:0 mapping:ffff8801ca470840 index:0x0 compound_mapcount: 0 flags: 0x200000000008100(slab|head) raw: 0200000000008100 ffff8801ca470840 0000000000000000 0000000100000001 raw: ffffea00072c9820 ffffea00072cc420 ffff8801dac02200 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801ca473b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801ca473b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801ca473c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801ca473c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801ca473d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================