[v5.15] Internal error in ext4_ioctl

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c79648372d02 Linux 5.15.189
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1532d5bc580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=1902d8bed658a98ccf7d
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7ab49562317a/disk-c7964837.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e847ec1e38d3/vmlinux-c7964837.xz
kernel image: https://storage.googleapis.com/syzbot-assets/263158c6371c/Image-c7964837.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1902d8...@syzkaller.appspotmail.com

Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 4160 Comm: syz.0.7 Not tainted 5.15.189-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 42400405 (nZcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=jc)
pc : __ext4_ioctl fs/ext4/ioctl.c:888 [inline]
pc : ext4_ioctl+0x2120/0x3614 fs/ext4/ioctl.c:1282
lr : __ext4_ioctl fs/ext4/ioctl.c:888 [inline]
lr : ext4_ioctl+0x20f4/0x3614 fs/ext4/ioctl.c:1282
sp : ffff80001fd878c0
x29: ffff80001fd87cd0 x28: ffff80001fd878e0 x27: ffff700003fb0f1c
x26: ffff0000d423e000 x25: 0000000000000000 x24: ffff0000dc014000
x23: ffff0000df0c34a0 x22: ffff0000df0c3478 x21: 00000000fffffff2
x20: dfff800000000000 x19: 1fffe0001be18694 x18: 0000000000000000
x17: ffff800016d04000 x16: ffff800008cc3cac x15: ffff8000167e4500
x14: ffff0000cca82540 x13: dfff800000000000 x12: 0000000000ff0100
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000ffffffffffff
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff800016e8c4f8 x4 : 0000000000000002 x3 : ffff8000082bfb8c
x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
__ext4_ioctl fs/ext4/ioctl.c:888 [inline]
ext4_ioctl+0x2120/0x3614 fs/ext4/ioctl.c:1282
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: ea29011f 9a9f016a d503229f b8400959 (2a1503e1)
---[ end trace 8b2ba887e1ff9b98 ]---
----------------
Code disassembly (best guess):
0: ea29011f bics xzr, x8, x9
4: 9a9f016a csel x10, x11, xzr, eq // eq = none
8: d503229f csdb
c: b8400959 ldtr w25, [x10]
* 10: 2a1503e1 mov w1, w21 <-- trapping instruction


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: c79648372d02 Linux 5.15.189
git tree: linux-5.15.y

console output: https://syzkaller.appspot.com/x/log.txt?x=121f19a2580000

kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=1902d8bed658a98ccf7d
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
userspace arch: arm64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=161f19a2580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=172529a2580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7ab49562317a/disk-c7964837.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e847ec1e38d3/vmlinux-c7964837.xz
kernel image: https://storage.googleapis.com/syzbot-assets/263158c6371c/Image-c7964837.gz.xz

mounted in repro: https://storage.googleapis.com/syzbot-assets/68914563f0c1/mount_0.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=17d00af0580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1902d8...@syzkaller.appspotmail.com

loop0: detected capacity change from 0 to 4096
EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue. Quota mode: writeback.

Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:

CPU: 1 PID: 4405 Comm: syz.0.17 Not tainted 5.15.189-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 42400405 (nZcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=jc)

pc : ext4_shutdown fs/ext4/ioctl.c:567 [inline]
pc : __ext4_ioctl fs/ext4/ioctl.c:1254 [inline]
pc : ext4_ioctl+0x1d44/0x3614 fs/ext4/ioctl.c:1282
lr : ext4_shutdown fs/ext4/ioctl.c:567 [inline]
lr : __ext4_ioctl fs/ext4/ioctl.c:1254 [inline]
lr : ext4_ioctl+0x1d1c/0x3614 fs/ext4/ioctl.c:1282
sp : ffff80001fcf78c0
x29: ffff80001fcf7cd0 x28: dfff800000000000 x27: ffff700003f9ef1c
x26: 1fffe00019199ccf x25: ffff0000c8ccc000 x24: ffff0000c8cce000
x23: ffff0000c1d93680 x22: 0000000000000000 x21: 0000000000000000
x20: ffff0000c8cce678 x19: 00000000fffffff2 x18: 0000000000000000
x17: 0000000000000000 x16: ffff800008cc38d0 x15: 00000000c0c0583b
x14: 0000000000ff0100 x13: 1ffff0000282e06b x12: 0000000000ff0100

x11: 0000000000000000 x10: 0000000000000000 x9 : 0000ffffffffffff

x8 : 0000000000000000 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
ext4_shutdown fs/ext4/ioctl.c:567 [inline]
__ext4_ioctl fs/ext4/ioctl.c:1254 [inline]
ext4_ioctl+0x1d44/0x3614 fs/ext4/ioctl.c:1282

vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Code: ea29011f 9a9f02aa d503229f b8400956 (2a1303e1)
---[ end trace 0d562abdae00a9ae ]---

----------------
Code disassembly (best guess):
0: ea29011f bics xzr, x8, x9

4: 9a9f02aa csel x10, x21, xzr, eq // eq = none
8: d503229f csdb
c: b8400956 ldtr w22, [x10]
* 10: 2a1303e1 mov w1, w19 <-- trapping instruction


---
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