[v5.15] Internal error in pipe_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=1359c1a2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=2b8806a38c55a49a4889
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+2b8806...@syzkaller.appspotmail.com

Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 5024 Comm: syz.6.212 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 : pipe_ioctl+0x3ac/0x448 fs/pipe.c:630
lr : sign_extend64 include/linux/bitops.h:183 [inline]
lr : __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:244 [inline]
lr : pipe_ioctl+0x390/0x448 fs/pipe.c:630
sp : ffff80001f827980
x29: ffff80001f8279a0 x28: 0000000000001fff x27: ffff0000f0c00000
x26: 0000000000ffff50 x25: dfff800000000000 x24: 0000000000000000
x23: 0000000000001000 x22: ffff0000f0c2800c x21: 0000000000000000
x20: 0000000000000001 x19: 0000000000000008 x18: 0000000000000002
x17: 0000000040000000 x16: ffff8000088fdd5c x15: 0000000000000002
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:
pipe_ioctl+0x3ac/0x448 fs/pipe.c:630
vfs_ioctl fs/ioctl.c:51 [inline]
do_vfs_ioctl+0xbe0/0x2370 fs/ioctl.c:834
__do_sys_ioctl fs/ioctl.c:872 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__arm64_sys_ioctl+0xe4/0x1c8 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: 9a9f030b d503229f 2a1f03e8 b800097a (93407d00)
---[ end trace 10816be83c0c1425 ]---
----------------
Code disassembly (best guess):
0: 9a9f030b csel x11, x24, xzr, eq // eq = none
4: d503229f csdb
8: 2a1f03e8 mov w8, wzr
c: b800097a sttr w26, [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=15970af0580000

kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=2b8806a38c55a49a4889
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=143d4842580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15cda9a2580000

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+2b8806...@syzkaller.appspotmail.com

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

CPU: 1 PID: 4246 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 : pipe_ioctl+0x3ac/0x448 fs/pipe.c:630
lr : sign_extend64 include/linux/bitops.h:183 [inline]
lr : __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:244 [inline]
lr : pipe_ioctl+0x390/0x448 fs/pipe.c:630

sp : ffff80001fe87980
x29: ffff80001fe879a0 x28: dfff800000000000 x27: ffff700003fd0f48
x26: 0000000000000000 x25: dfff800000000000 x24: 0000000000000000
x23: 0000000000000000 x22: 0000000000000010 x21: 0000000000000000
x20: 0000000000000001 x19: 0000000000000000 x18: 0000000000000000
x17: 0000000000000000 x16: ffff8000088fdd5c x15: 0000000000005761
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:
pipe_ioctl+0x3ac/0x448 fs/pipe.c:630
vfs_ioctl fs/ioctl.c:51 [inline]
do_vfs_ioctl+0xbe0/0x2370 fs/ioctl.c:834
__do_sys_ioctl fs/ioctl.c:872 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__arm64_sys_ioctl+0xe4/0x1c8 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: 9a9f030b d503229f 2a1f03e8 b800097a (93407d00)

---[ end trace 7f64cb05ede1c9bf ]---

----------------
Code disassembly (best guess):
0: 9a9f030b csel x11, x24, xzr, eq // eq = none
4: d503229f csdb
8: 2a1f03e8 mov w8, wzr
c: b800097a sttr w26, [x11]
* 10: 93407d00 sxtw x0, w8 <-- trapping instruction


---

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