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Subject[syzbot] BUG: unable to handle kernel NULL pointer dereference in log_replay
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Hello,

syzbot found the following issue on:

HEAD commit: a41a877bc12d Merge branch 'for-next/fixes' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=15eebce7080000
kernel config: https://syzkaller.appspot.com/x/.config?x=5cea15779c42821c
dashboard link: https://syzkaller.appspot.com/bug?extid=8379f446e2ac4365e343
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8379f446e2ac4365e343@syzkaller.appspotmail.com

ntfs3: loop4: ino=2, "/" ntfs_iget5
ntfs3: loop4: Mark volume as dirty due to NTFS errors
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Mem abort info:
ESR = 0x0000000096000006
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x06: level 2 translation fault
Data abort info:
ISV = 0, ISS = 0x00000006
CM = 0, WnR = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=000000013af0c000
[0000000000000000] pgd=080000013af11003, p4d=080000013af11003, pud=0800000138a68003, pmd=0000000000000000
Internal error: Oops: 96000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 17646 Comm: syz-executor.4 Not tainted 6.0.0-rc2-syzkaller-16455-ga41a877bc12d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : log_replay+0x4c/0x3024 fs/ntfs3/fslog.c:3774
lr : log_replay+0x3c/0x3024 fs/ntfs3/fslog.c:3736
sp : ffff80002180b970
x29: ffff80002180ba80 x28: ffff0000f8a8e000 x27: ffff0000dac28000
x26: 0000000000000018 x25: 0000000000000024 x24: ffff80002180baf4
x23: 0000000000000030 x22: ffff00010acaff40 x21: ffff0000f8a8c000
x20: 0000000000000000 x19: ffff0000f8a8e000 x18: 00000000000000c0
x17: ffff80000dd7a698 x16: ffff80000dbb8658 x15: ffff0000f666cf80
x14: 0000000000000120 x13: 00000000ffffffff x12: ffff0000f666cf80
x11: ff80800008bf6e60 x10: 0000000000000000 x9 : ffff800008bf6e60
x8 : ffff0000f666cf80 x7 : ffff8000085f0604 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000001 x1 : ffff80002180baf4 x0 : ffff00010acaff40
Call trace:
log_replay+0x4c/0x3024 fs/ntfs3/fslog.c:3762
ntfs_loadlog_and_replay+0x114/0x1ec fs/ntfs3/fsntfs.c:299
ntfs_fill_super+0xc10/0x14a4 fs/ntfs/super.c:2904
get_tree_bdev+0x1e8/0x2a0 fs/super.c:1323
ntfs_fs_get_tree+0x28/0x38 fs/ntfs3/super.c:1358
vfs_get_tree+0x40/0x140 fs/super.c:1530
do_new_mount+0x1dc/0x4e4 fs/namespace.c:3040
path_mount+0x358/0x914 fs/namespace.c:3370
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__arm64_sys_mount+0x2f8/0x408 fs/namespace.c:3568
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall arch/arm64/kernel/syscall.c:52 [inline]
el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x48/0x154 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:624
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:642
el0t_64_sync+0x18c/0x190
Code: f9400ed4 a93b7fbf f90047ff b942a2d7 (f9400288)
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
0: f9400ed4 ldr x20, [x22, #24]
4: a93b7fbf stp xzr, xzr, [x29, #-80]
8: f90047ff str xzr, [sp, #136]
c: b942a2d7 ldr w23, [x22, #672]
* 10: f9400288 ldr x8, [x20] <-- trapping instruction


---
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