[v5.15] Internal error in ns_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=13d28ba2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=5cdbdc388e3b27db7f57
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+5cdbdc...@syzkaller.appspotmail.com

netlink: 830 bytes leftover after parsing attributes in process `syz.4.68'.
device bond_slave_0 entered promiscuous mode
device bond_slave_1 entered promiscuous mode
Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4291 Comm: syz.4.68 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 : ns_ioctl+0x41c/0x504 fs/nsfs.c:211
lr : sign_extend64 include/linux/bitops.h:183 [inline]
lr : __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:244 [inline]
lr : ns_ioctl+0x400/0x504 fs/nsfs.c:211
sp : ffff80001fc17c80
x29: ffff80001fc17ce0 x28: ffff0000d9f43680 x27: 0000000000000003
x26: 1fffe0001b3e86d0 x25: 0000000000400140 x24: 1ffff00003f82f90
x23: dfff800000000000 x22: 0000000000000000 x21: 0000000000000001
x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000000
x17: 0000000000000002 x16: ffff8000089b5828 x15: 000000000000b704
x14: 0000000000ff0100 x13: 1ffff0000282e06b x12: 0000000000080000
x11: 0000000000000000 x10: 0000ffffffffffff x9 : 0000000000000000
x8 : 00000000fffffff2 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
ns_ioctl+0x41c/0x504 fs/nsfs.c:211
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: ea2a013f 9a9f026b d503229f b8000974 (93407d00)
---[ end trace dd8be869ef19f9f7 ]---
----------------
Code disassembly (best guess):
0: ea2a013f bics xzr, x9, x10
4: 9a9f026b csel x11, x19, xzr, eq // eq = none
8: d503229f csdb
c: b8000974 sttr w20, [x11]
* 10: 93407d00 sxtw x0, w8 <-- 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=15edcba2580000

kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=5cdbdc388e3b27db7f57
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=12787af0580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=144013a2580000

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+5cdbdc...@syzkaller.appspotmail.com

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

CPU: 1 PID: 4225 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 : ns_ioctl+0x41c/0x504 fs/nsfs.c:211
lr : sign_extend64 include/linux/bitops.h:183 [inline]
lr : __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:244 [inline]
lr : ns_ioctl+0x400/0x504 fs/nsfs.c:211

sp : ffff80001fd87c80
x29: ffff80001fd87ce0 x28: ffff0000d7b551c0 x27: 0000000000000003
x26: 1fffe0001af6aa38 x25: 0000000000400040 x24: 1ffff00003fb0f90

x23: dfff800000000000 x22: 0000000000000000 x21: 0000000000000001
x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000000

x17: 0000000000000000 x16: ffff8000089b5828 x15: 000000000000b704
x14: 0000000000ff0100 x13: 1ffff0000282e06b x12: 0000000000ff0100

x11: 0000000000000000 x10: 0000ffffffffffff x9 : 0000000000000000
x8 : 00000000fffffff2 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
ns_ioctl+0x41c/0x504 fs/nsfs.c:211
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: ea2a013f 9a9f026b d503229f b8000974 (93407d00)

---[ end trace 8caf5c97f395b51d ]---

----------------
Code disassembly (best guess):
0: ea2a013f bics xzr, x9, x10
4: 9a9f026b csel x11, x19, xzr, eq // eq = none
8: d503229f csdb
c: b8000974 sttr w20, [x11]
* 10: 93407d00 sxtw x0, w8 <-- trapping instruction


---

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