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BUG: KASAN: use-after-free in arch_local_irq_enable arch/x86/include/asm/paravirt.h:787 [inline]
BUG: KASAN: use-after-free in __do_page_fault+0xc03/0xd60 arch/x86/mm/fault.c:1357
Read of size 8 at addr ffff8801d1125680 by task syz-executor7/5189

CPU: 0 PID: 5189 Comm: syz-executor7 Not tainted 4.14.0-rc4-next-20171009+ #33
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
RDS: rds_bind could not find a transport for 172.20.0.170, load rds_tcp or rds_rdma?
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430
 arch_local_irq_enable arch/x86/include/asm/paravirt.h:787 [inline]
 __do_page_fault+0xc03/0xd60 arch/x86/mm/fault.c:1357
 do_page_fault+0xee/0x720 arch/x86/mm/fault.c:1520
 page_fault+0x22/0x30 arch/x86/entry/entry_64.S:1066
RIP: 0033:0x44bcf0
RSP: 002b:00007f1e2677b758 EFLAGS: 00010202
RAX: 00007f1e2677b800 RBX: 0000000000718000 RCX: 000000000000000e
RDX: 0000000000000400 RSI: 0000000020012fe0 RDI: 00007f1e2677b800
RBP: 0000000000005e10 R08: 0000000000000400 R09: 0000000000000000
R10: 00000000000f4245 R11: 0000000000000206 R12: 00000000004bbc27
R13: 00000000ffffffff R14: 0000000020012fee R15: 0000000000000000

Allocated by task 5189:
 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
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3562
 kmem_cache_zalloc include/linux/slab.h:687 [inline]
 mmap_region+0x7ee/0x15a0 mm/mmap.c:1658
 do_mmap+0x6a1/0xd50 mm/mmap.c:1468
 do_mmap_pgoff include/linux/mm.h:2180 [inline]
 vm_mmap_pgoff+0x1de/0x280 mm/util.c:333
 SYSC_mmap_pgoff mm/mmap.c:1518 [inline]
 SyS_mmap_pgoff+0x23b/0x5f0 mm/mmap.c:1476
 SYSC_mmap arch/x86/kernel/sys_x86_64.c:99 [inline]
 SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:90
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Freed by task 5209:
 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:3504 [inline]
 kmem_cache_free+0x77/0x280 mm/slab.c:3764
 remove_vma+0x162/0x1b0 mm/mmap.c:176
 remove_vma_list mm/mmap.c:2476 [inline]
 do_munmap+0x82a/0xdf0 mm/mmap.c:2715
 mmap_region+0x59e/0x15a0 mm/mmap.c:1631
 do_mmap+0x6a1/0xd50 mm/mmap.c:1468
 do_mmap_pgoff include/linux/mm.h:2180 [inline]
 vm_mmap_pgoff+0x1de/0x280 mm/util.c:333
 SYSC_mmap_pgoff mm/mmap.c:1518 [inline]
 SyS_mmap_pgoff+0x23b/0x5f0 mm/mmap.c:1476
 SYSC_mmap arch/x86/kernel/sys_x86_64.c:99 [inline]
 SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:90
 entry_SYSCALL_64_fastpath+0x1f/0xbe

The buggy address belongs to the object at ffff8801d1125630
 which belongs to the cache vm_area_struct of size 200
The buggy address is located 80 bytes inside of
 200-byte region [ffff8801d1125630, ffff8801d11256f8)
The buggy address belongs to the page:
page:ffffea0007444940 count:1 mapcount:0 mapping:ffff8801d1125000 index:0x0
flags: 0x200000000000100(slab)
raw: 0200000000000100 ffff8801d1125000 0000000000000000 000000010000000f
raw: ffffea0007444020 ffffea0007444ca0 ffff8801dae049c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d1125580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
 ffff8801d1125600: fc fc fc fc fc fc fb fb fb fb fb fb fb fb fb fb
>ffff8801d1125680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc
                   ^
 ffff8801d1125700: fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 00
 ffff8801d1125780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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