BUG: Bad page map in process syz-executor.1  pte:207200720 pmd:212afd067
addr:0000000020000000 vm_flags:08100077 anon_vma:ffff88808bb0ca00 mapping:0000000000000000 index:20000
file:(null) fault:0x0 mmap:0x0 readpage:0x0
CPU: 1 PID: 22348 Comm: syz-executor.1 Not tainted 5.9.0-rc2-next-20200824-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_bad_pte.cold+0x1e6/0x219 mm/memory.c:547
 vm_normal_page+0x224/0x380 mm/memory.c:610
 zap_pte_range mm/memory.c:1064 [inline]
 zap_pmd_range mm/memory.c:1195 [inline]
 zap_pud_range mm/memory.c:1224 [inline]
 zap_p4d_range mm/memory.c:1245 [inline]
 unmap_page_range+0xba2/0x2ab0 mm/memory.c:1266
 unmap_single_vma+0x198/0x300 mm/memory.c:1311
 unmap_vmas+0x168/0x2e0 mm/memory.c:1343
 exit_mmap+0x2b1/0x530 mm/mmap.c:3228
 __mmput+0x122/0x470 kernel/fork.c:1075
 mmput+0x53/0x60 kernel/fork.c:1096
 exit_mm kernel/exit.c:483 [inline]
 do_exit+0xa8b/0x29f0 kernel/exit.c:793
 do_group_exit+0x125/0x310 kernel/exit.c:903
 get_signal+0x428/0x1f00 kernel/signal.c:2757
 arch_do_signal+0x82/0x2520 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:136 [inline]
 exit_to_user_mode_prepare+0x15d/0x1c0 kernel/entry/common.c:167
 syscall_exit_to_user_mode+0x59/0x2b0 kernel/entry/common.c:242
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d579
Code: Bad RIP value.
RSP: 002b:00007f2ad5797cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000118cf48 RCX: 000000000045d579
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000118cf48
RBP: 000000000118cf40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffd6a7dc72f R14: 00007f2ad57989c0 R15: 000000000118cf4c
BUG: Bad rss-counter state mm:000000007b8f42bb type:MM_ANONPAGES val:1