[syzbot] BUG: unable to handle kernel NULL pointer dereference in dir_search_u

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6d464646530f Merge branch 'for-next/core' 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=17244a4b880000
kernel config: https://syzkaller.appspot.com/x/.config?x=23eec5c79c22aaf8
dashboard link: https://syzkaller.appspot.com/bug?extid=decdb33311f46369f416
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
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1430138d880000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=108c8fed880000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f22d29413625/disk-6d464646.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/389f0a5f1a4a/vmlinux-6d464646.xz
kernel image: https://storage.googleapis.com/syzbot-assets/48ddb02d82da/Image-6d464646.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/3f65b6de0e07/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+decdb3...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 8192
ntfs3: loop0: Different NTFS' sector size (4096) and media sector size (512)
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Mem abort info:
ESR = 0x0000000086000006
EC = 0x21: IABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x06: level 2 translation fault
user pgtable: 4k pages, 48-bit VAs, pgdp=000000010d1aa000
[0000000000000000] pgd=080000010d1ce003, p4d=080000010d1ce003, pud=080000010d251003, pmd=0000000000000000
Internal error: Oops: 0000000086000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 3109 Comm: syz-executor169 Not tainted 6.1.0-rc6-syzkaller-32662-g6d464646530f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : 0x0
lr : hdr_find_e fs/ntfs3/index.c:708 [inline]
lr : indx_find+0x3b0/0x954 fs/ntfs3/index.c:1068
sp : ffff80000ff6b8c0
x29: ffff80000ff6ba40 x28: 0000000000000000 x27: 0000000000000148
x26: ffff0000c9257000 x25: ffff0000c93d8278 x24: 0000000000000000
x23: 0000000000000000 x22: 0000000000000000 x21: 0000000000000003
x20: 0000000000000138 x19: 0000000000000002 x18: 0000000000000098
x17: ffff80000c0cd83c x16: ffff80000dbe6158 x15: ffff0000ce01cec0
x14: 0000000000000010 x13: 0000000000000000 x12: ffff0000ce01cec0
x11: ff80800008c11e14 x10: 0000000000000000 x9 : ffff800008c11e14
x8 : ffff0000ce01cec0 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 2400490033003000 x4 : ffff0000c9257000 x3 : 0000000000000000
x2 : ffff0000c93d8288 x1 : 0000000000000000 x0 : ffff80000c1f232e
Call trace:
0x0
dir_search_u+0xa4/0x1e0 fs/ntfs3/dir.c:254
ntfs_extend_init+0xe4/0x238 fs/ntfs3/fsntfs.c:214
ntfs_fill_super+0x143c/0x14a4 fs/ntfs3/super.c:1243
get_tree_bdev+0x1e8/0x2a0 fs/super.c:1324
ntfs_fs_get_tree+0x28/0x38 fs/ntfs3/super.c:1358
vfs_get_tree+0x40/0x140 fs/super.c:1531
do_new_mount+0x1dc/0x4e4 fs/namespace.c:3040
path_mount+0x358/0x890 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+0x2c4/0x3c4 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+0x48/0x164 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584
Code: bad PC value
---[ end trace 0000000000000000 ]---


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[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.