syzbot

random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
BUG: unable to handle kernel paging request at ffffeafff9038020
IP: [<ffffffff814f5937>] __read_once_size include/linux/compiler.h:243 [inline]
IP: [<ffffffff814f5937>] compound_head include/linux/page-flags.h:143 [inline]
IP: [<ffffffff814f5937>] PageAnon include/linux/page-flags.h:386 [inline]
IP: [<ffffffff814f5937>] page_remove_rmap+0x37/0x6d0 mm/rmap.c:1429
PGD 0 [   29.604004] 
Oops: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 3766 Comm: syz-executor142 Not tainted 4.9.122-g54068d6 #78
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801bd2c8000 task.stack: ffff8801bd3f8000
RIP: 0010:[<ffffffff814f5937>]  [<ffffffff814f5937>] __read_once_size include/linux/compiler.h:243 [inline]
RIP: 0010:[<ffffffff814f5937>]  [<ffffffff814f5937>] compound_head include/linux/page-flags.h:143 [inline]
RIP: 0010:[<ffffffff814f5937>]  [<ffffffff814f5937>] PageAnon include/linux/page-flags.h:386 [inline]
RIP: 0010:[<ffffffff814f5937>]  [<ffffffff814f5937>] page_remove_rmap+0x37/0x6d0 mm/rmap.c:1429
RSP: 0018:ffff8801bd3ff948  EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffffeafff9038000 RCX: 0000000000000000
RDX: 1ffffd5fff207004 RSI: ffffffff814f5918 RDI: ffffeafff9038000
RBP: ffff8801bd3ff970 R08: 0000000000035060 R09: 0000000000000001
R10: ffff8801bd2c8000 R11: 0000000000000001 R12: ffff8801bd3ffc08
R13: ffffeafff9038020 R14: ffffeafff9038000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffeafff9038020 CR3: 00000001c5afd000 CR4: 00000000001606f0
Stack:
 ffffeafff9038020 ffff8801bd3ffc08 ffff8801cb2ea800 ffffeafff9038000
 ffff8801c3d41210 ffff8801bd3ff9c8 ffffffff8154cb8f ffff8801bd3ffc18
 ffff8801bd3ffc10 ffff8801bd3ffc88 00003ffe40e001e0 00000001cb2ea000
Call Trace:
 [<ffffffff8154cb8f>] zap_huge_pmd+0x16f/0x860 mm/huge_memory.c:1428
 [<ffffffff814cae6d>] zap_pmd_range mm/memory.c:1245 [inline]
 [<ffffffff814cae6d>] zap_pud_range mm/memory.c:1279 [inline]
 [<ffffffff814cae6d>] unmap_page_range+0x12ad/0x1730 mm/memory.c:1300
 [<ffffffff814cb3f1>] unmap_single_vma+0x101/0x260 mm/memory.c:1345
 [<ffffffff814cbd32>] unmap_vmas+0x102/0x1d0 mm/memory.c:1375
 [<ffffffff814e4834>] exit_mmap+0x214/0x3f0 mm/mmap.c:3020
 [<ffffffff8112db23>] __mmput kernel/fork.c:884 [inline]
 [<ffffffff8112db23>] mmput+0xf3/0x2d0 kernel/fork.c:906
 [<ffffffff81143056>] exit_mm kernel/exit.c:514 [inline]
 [<ffffffff81143056>] do_exit+0x906/0x27b0 kernel/exit.c:820
 [<ffffffff81149211>] do_group_exit+0x111/0x340 kernel/exit.c:937
 [<ffffffff8114945d>] SYSC_exit_group kernel/exit.c:948 [inline]
 [<ffffffff8114945d>] SyS_exit_group+0x1d/0x20 kernel/exit.c:946
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff83a00cd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: 55 41 54 53 48 89 fb e8 58 b4 e6 ff 4c 8d 6b 20 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 b8 05 00 00 <4c> 8b 73 20 49 89 dc 41 f6 c6 01 0f 85 4b 03 00 00 e8 23 b4 e6 
RIP  [<ffffffff814f5937>] __read_once_size include/linux/compiler.h:243 [inline]
RIP  [<ffffffff814f5937>] compound_head include/linux/page-flags.h:143 [inline]
RIP  [<ffffffff814f5937>] PageAnon include/linux/page-flags.h:386 [inline]
RIP  [<ffffffff814f5937>] page_remove_rmap+0x37/0x6d0 mm/rmap.c:1429
 RSP <ffff8801bd3ff948>
CR2: ffffeafff9038020
---[ end trace da4732a81093a060 ]---