syzbot


BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio

Status: upstream: reported on 2026/06/30 01:37
Reported-by: syzbot+b95765d1ee2f94925081@syzkaller.appspotmail.com
First crash: 19d, last: 19d
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio (3) erofs 10 C 492 613d 670d 28/29 fixed on 2024/11/12 23:31
upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio (4) fs 10 C done 5746 180d 609d 29/29 fixed on 2026/05/06 16:40
upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio fs mm 10 8 1358d 1368d 0/29 auto-obsoleted due to no activity on 2023/02/26 19:26
upstream BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio (2) fs 10 6 1132d 1182d 0/29 auto-obsoleted due to no activity on 2023/09/20 22:50
android-6-12 BUG: unable to handle kernel paging request in filemap_read_folio origin:upstream 8 C 22 155d 388d 0/1 auto-obsoleted due to no activity on 2026/05/15 00:20

Sample crash report:
ntfs: volume version 3.1.
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 7cf8d067 P4D 7cf8d067 PUD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 11906 Comm: syz.2.3511 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffc90003a277b8 EFLAGS: 00010283
RAX: ffffffff81aca885 RBX: ffffea00013631c0 RCX: 0000000000080000
RDX: ffffc900133b9000 RSI: ffffea00013631c0 RDI: 0000000000000000
RBP: ffffc90003a27878 R08: ffffea00013631c7 R09: 1ffffd400026c638
R10: dffffc0000000000 R11: fffff9400026c639 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffffd400026c639 R15: 1ffff92000744efc
FS:  00007f1cd50196c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000070818000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 filemap_read_folio+0x164/0x7a0 mm/filemap.c:2490
 do_read_cache_folio+0x29e/0x790 mm/filemap.c:3659
 do_read_cache_page+0x32/0x230 mm/filemap.c:3701
 read_mapping_page include/linux/pagemap.h:793 [inline]
 ntfs_map_page fs/ntfs/aops.h:75 [inline]
 ntfs_check_logfile+0x28f/0x25c0 fs/ntfs/logfile.c:532
 load_and_check_logfile+0x6f/0xd0 fs/ntfs/super.c:1215
 load_system_files+0x2ecc/0x44f0 fs/ntfs/super.c:1941
 ntfs_fill_super+0x187c/0x2ac0 fs/ntfs/super.c:2892
 mount_bdev+0x28a/0x3c0 fs/super.c:1443
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x247/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1cd419e0ca
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1cd5018e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f1cd5018ee0 RCX: 00007f1cd419e0ca
RDX: 0000200000000100 RSI: 000020000001ecc0 RDI: 00007f1cd5018ea0
RBP: 0000200000000100 R08: 00007f1cd5018ee0 R09: 0000000000008000
R10: 0000000000008000 R11: 0000000000000246 R12: 000020000001ecc0
R13: 00007f1cd5018ea0 R14: 000000000001ec7e R15: 0000200000000200
 </TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 0018:ffffc90003a277b8 EFLAGS: 00010283
RAX: ffffffff81aca885 RBX: ffffea00013631c0 RCX: 0000000000080000
RDX: ffffc900133b9000 RSI: ffffea00013631c0 RDI: 0000000000000000
RBP: ffffc90003a27878 R08: ffffea00013631c7 R09: 1ffffd400026c638
R10: dffffc0000000000 R11: fffff9400026c639 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffffd400026c639 R15: 1ffff92000744efc
FS:  00007f1cd50196c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000070818000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/30 01:36 linux-6.1.y fdb6fcb41cc7 fff8d0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan BUG: unable to handle kernel NULL pointer dereference in filemap_read_folio
* Struck through repros no longer work on HEAD.