BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 62ebc067 P4D 62ebc067 PUD 62ebd067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 9580 Comm: syz-executor.0 Not tainted 5.7.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x43/0x60 kernel/kcov.c:202
Code: 24 74 0f 80 e6 01 74 35 8b 90 04 14 00 00 85 d2 74 2b 8b 90 e0 13 00 00 83 fa 02 75 20 48 8b 88 e8 13 00 00 8b 80 e4 13 00 00 <48> 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 66 0f
RSP: 0018:ffffc900020776a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 800000006fbd3007 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff81a2c1ae RDI: 0000000000000007
RBP: 1ffff9200040eed5 R08: ffff888061d48080 R09: fffff9400037de91
R10: ffffea0001bef487 R11: fffff9400037de90 R12: ffff888062ea2da8
R13: 00007f720038c000 R14: 0000000000000001 R15: 00007f720038c000
FS:  00007f71ffae9700(0000) GS:ffff88802cf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000062f13000 CR4: 0000000000340ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 pte_pfn arch/x86/include/asm/pgtable.h:217 [inline]
 vm_normal_page+0x1ae/0x380 mm/memory.c:595
 smaps_pte_entry fs/proc/task_mmu.c:500 [inline]
 smaps_pte_range+0xafe/0x1990 fs/proc/task_mmu.c:602
 walk_pmd_range mm/pagewalk.c:89 [inline]
 walk_pud_range mm/pagewalk.c:160 [inline]
 walk_p4d_range mm/pagewalk.c:193 [inline]
 walk_pgd_range mm/pagewalk.c:229 [inline]
 __walk_page_range+0xcfb/0x2070 mm/pagewalk.c:331
 walk_page_vma+0x227/0x2e0 mm/pagewalk.c:482
 smap_gather_stats+0xca/0x1e0 fs/proc/task_mmu.c:756
 show_smaps_rollup+0x46f/0x720 fs/proc/task_mmu.c:857
 seq_read+0x432/0xfd0 fs/seq_file.c:208
 do_loop_readv_writev fs/read_write.c:715 [inline]
 do_loop_readv_writev fs/read_write.c:702 [inline]
 do_iter_read+0x483/0x650 fs/read_write.c:936
 vfs_readv+0xf0/0x160 fs/read_write.c:1054
 do_preadv+0x1bc/0x270 fs/read_write.c:1146
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45c879
Code: 1d b2 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb b1 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f71ffae8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 000000000074bfa0 RCX: 000000000045c879
RDX: 00000000000003da RSI: 00000000200017c0 RDI: 0000000000000003
RBP: 000000000070ee40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f71ffae96d4
R13: 0000000000000862 R14: 00000000006ed5c0 R15: 00000000004b219d
Modules linked in:
CR2: 0000000000000000
---[ end trace cdef1382ca003f03 ]---
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x43/0x60 kernel/kcov.c:202
Code: 24 74 0f 80 e6 01 74 35 8b 90 04 14 00 00 85 d2 74 2b 8b 90 e0 13 00 00 83 fa 02 75 20 48 8b 88 e8 13 00 00 8b 80 e4 13 00 00 <48> 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 66 0f
RSP: 0018:ffffc900020776a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 800000006fbd3007 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff81a2c1ae RDI: 0000000000000007
RBP: 1ffff9200040eed5 R08: ffff888061d48080 R09: fffff9400037de91
R10: ffffea0001bef487 R11: fffff9400037de90 R12: ffff888062ea2da8
R13: 00007f720038c000 R14: 0000000000000001 R15: 00007f720038c000
FS:  00007f71ffae9700(0000) GS:ffff88802cf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000062f13000 CR4: 0000000000340ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400