BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 9d987067 P4D 9d987067 PUD 9e477067 PMD 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 17128 Comm: syz-executor.5 Not tainted 5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x60 kernel/kcov.c:202
Code: c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 04 14 00 00 00 74 2c 8b 91 e0 13 00 00 83 fa 02 75 21 48 8b 91 e8 13 00 00 <48> 8b 32 48 8d 7e 01 8b 89 e4 13 00 00 48 39 cf 73 08 48 89 44 f2
RSP: 0018:ffffc900071ef500 EFLAGS: 00010246
RAX: ffffffff8170d67d RBX: ffffffff892de510 RCX: ffff8880a8600000
RDX: 0000000000000000 RSI: 000000000000233e RDI: 000000000000233f
RBP: 00000000fffffffe R08: ffffffff8170d5a0 R09: ffffed100c14286b
R10: ffffed100c14286b R11: 0000000000000000 R12: dffffc0000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f985435b700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000094122000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
map_id_up kernel/user_namespace.c:366 [inline]
from_kgid+0x1bd/0x2e0 kernel/user_namespace.c:476
i_gid_read include/linux/fs.h:1577 [inline]
ext4_do_update_inode fs/ext4/inode.c:4954 [inline]
ext4_mark_iloc_dirty+0x425/0x30c0 fs/ext4/inode.c:5600
ext4_mark_inode_dirty+0x3ed/0x4f0 fs/ext4/inode.c:5793
ext4_dirty_inode+0xd2/0x110 fs/ext4/inode.c:5824
__mark_inode_dirty+0xb4/0x670 fs/fs-writeback.c:2257
generic_update_time+0x1f0/0x210 fs/inode.c:1682
update_time fs/inode.c:1695 [inline]
file_update_time+0x325/0x380 fs/inode.c:1910
ext4_write_checks fs/ext4/file.c:249 [inline]
ext4_buffered_write_iter+0x2ef/0x5d0 fs/ext4/file.c:265
ext4_file_write_iter+0x6c1/0x1840 fs/ext4/file.c:491
do_iter_readv_writev+0x5b7/0x820 include/linux/fs.h:1911
do_iter_write+0x16a/0x540 fs/read_write.c:999
iter_file_splice_write+0x6ca/0xdf0 fs/splice.c:750
do_splice_from fs/splice.c:846 [inline]
direct_splice_actor+0xfa/0x2a0 fs/splice.c:1016
splice_direct_to_actor+0x4a2/0xb60 fs/splice.c:971
do_splice_direct+0x201/0x340 fs/splice.c:1059
do_sendfile+0x809/0xfe0 fs/read_write.c:1521
__do_sys_sendfile64 fs/read_write.c:1576 [inline]
__se_sys_sendfile64 fs/read_write.c:1568 [inline]
__x64_sys_sendfile64+0xed/0x1a0 fs/read_write.c:1568
do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca59
Code: 0d b7 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f985435ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000004fcea0 RCX: 000000000045ca59
RDX: 0000000020000140 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000007fff R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000008f3 R14: 00000000004cbc2c R15: 00007f985435b6d4
Modules linked in:
CR2: 0000000000000000
---[ end trace 8f4af864ebbfae7e ]---
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x3f/0x60 kernel/kcov.c:202
Code: c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 04 14 00 00 00 74 2c 8b 91 e0 13 00 00 83 fa 02 75 21 48 8b 91 e8 13 00 00 <48> 8b 32 48 8d 7e 01 8b 89 e4 13 00 00 48 39 cf 73 08 48 89 44 f2
RSP: 0018:ffffc900071ef500 EFLAGS: 00010246
RAX: ffffffff8170d67d RBX: ffffffff892de510 RCX: ffff8880a8600000
RDX: 0000000000000000 RSI: 000000000000233e RDI: 000000000000233f
RBP: 00000000fffffffe R08: ffffffff8170d5a0 R09: ffffed100c14286b
R10: ffffed100c14286b R11: 0000000000000000 R12: dffffc0000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007f985435b700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000094122000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400