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BUG: KASAN: slab-out-of-bounds in hlist_add_head include/linux/list.h:673 [inline]
BUG: KASAN: slab-out-of-bounds in enqueue_timer kernel/time/timer.c:520 [inline]
BUG: KASAN: slab-out-of-bounds in __internal_add_timer+0x275/0x2d0 kernel/time/timer.c:531
Write of size 8 at addr ffff88006730bc08 by task syz-fuzzer/3001

CPU: 2 PID: 3001 Comm: syz-fuzzer Not tainted 4.13.0-rc7-next-20170901+ #13
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 <IRQ>
 __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_add_head include/linux/list.h:673 [inline]
 enqueue_timer kernel/time/timer.c:520 [inline]
 __internal_add_timer+0x275/0x2d0 kernel/time/timer.c:531
 internal_add_timer kernel/time/timer.c:573 [inline]
 __mod_timer kernel/time/timer.c:1024 [inline]
 mod_timer+0x622/0x15b0 kernel/time/timer.c:1071
 rpm_suspend+0x126b/0x1610 drivers/base/power/runtime.c:533
 pm_suspend_timer_fn+0x166/0x1d0 drivers/base/power/runtime.c:909
 call_timer_fn+0x246/0x850 kernel/time/timer.c:1281
 expire_timers kernel/time/timer.c:1320 [inline]
 __run_timers+0x7fd/0xb90 kernel/time/timer.c:1620
 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:577
 </IRQ>
RIP: 0033:0x41f963
RSP: 002b:00007f53c8483d10 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff10
RAX: 000000c420020b60 RBX: 0000000000000036 RCX: 000000c420001080
RDX: 00007f53c4ae8c78 RSI: 0000000000000000 RDI: 0000000000000010
RBP: 00007f53c8483db0 R08: 0000000000000036 R09: ffffffffffffe420
R10: 0000000000000020 R11: 000000c430baca20 R12: 0000000000000000
R13: 0000000000000000 R14: 000000000045cef0 R15: 0000000000000000

Allocated by task 16544:
 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 mm/slab.c:3725 [inline]
 __kmalloc+0x162/0x760 mm/slab.c:3734
 kmalloc include/linux/slab.h:498 [inline]
 bio_alloc_bioset+0x404/0x750 block/bio.c:450
 bio_kmalloc include/linux/bio.h:422 [inline]
 bio_copy_user_iov+0x40e/0xe70 block/bio.c:1246
 __blk_rq_map_user_iov block/blk-map.c:59 [inline]
 blk_rq_map_user_iov+0x28c/0x7f0 block/blk-map.c:137
 blk_rq_map_user+0x111/0x180 block/blk-map.c:167
 sg_start_req drivers/scsi/sg.c:1786 [inline]
 sg_common_write.isra.17+0x1352/0x1cb0 drivers/scsi/sg.c:777
 sg_write+0x7a6/0xca0 drivers/scsi/sg.c:677
 __vfs_write+0xef/0x970 fs/read_write.c:468
 vfs_write+0x18f/0x510 fs/read_write.c:518
 SYSC_write fs/read_write.c:565 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:557
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Freed by task 15979:
 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:7962 [inline]
 free_netdev+0x2cf/0x360 net/core/dev.c:8124
 tun_set_iff drivers/net/tun.c:2091 [inline]
 __tun_chr_ioctl+0x2cf6/0x3d20 drivers/net/tun.c:2262
 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:2507
 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 ffff880067308800
 which belongs to the cache kmalloc-16384 of size 16384
The buggy address is located 13320 bytes inside of
 16384-byte region [ffff880067308800, ffff88006730c800)
The buggy address belongs to the page:
page:ffffea00019cc200 count:1 mapcount:0 mapping:ffff880067308800 index:0x0 compound_mapcount: 0
flags: 0x500000000008100(slab|head)
raw: 0500000000008100 ffff880067308800 0000000000000000 0000000100000001
raw: ffffea0001abd420 ffffea000125ca20 ffff88003e802200 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88006730bb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88006730bb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88006730bc00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                      ^
 ffff88006730bc80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88006730bd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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