[v5.15] Internal error in ptrace_request

[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=151d4af0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=7db3bf50736f702a7a41
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+7db3bf...@syzkaller.appspotmail.com

Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4193 Comm: syz.4.14 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 : ptrace_request+0xddc/0x1d00 kernel/ptrace.c:1253
lr : ptrace_request+0xdb0/0x1d00 kernel/ptrace.c:1253
sp : ffff80001ff47a20
x29: ffff80001ff47c90 x28: 0000000000000000 x27: ffff700003fe8f4c
x26: dfff800000000000 x25: 00000000fffffff2 x24: ffff0000d5d99b64
x23: ffff0000d5d99b40 x22: 0000000000004205 x21: 0000000000000002
x20: ffff0000dd13d1c0 x19: 0000000000000000 x18: 0000000000000000
x17: 0000000000000002 x16: ffff8000081b2c2c x15: 000000000000420f
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:
ptrace_request+0xddc/0x1d00 kernel/ptrace.c:1253
arch_ptrace+0x78/0x94 arch/arm64/kernel/ptrace.c:1794
__do_sys_ptrace kernel/ptrace.c:1328 [inline]
__se_sys_ptrace kernel/ptrace.c:1293 [inline]
__arm64_sys_ptrace+0x1d0/0x5a0 kernel/ptrace.c:1293
__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 9a9f026a d503229f f840095c (2a1903e1)
---[ end trace 1f6ce46b8c2a1727 ]---
----------------
Code disassembly (best guess):
0: ea29011f bics xzr, x8, x9
4: 9a9f026a csel x10, x19, xzr, eq // eq = none
8: d503229f csdb
c: f840095c ldtr x28, [x10]
* 10: 2a1903e1 mov w1, w25 <-- trapping instruction


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[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=150d96f0580000

kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=7db3bf50736f702a7a41
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=1373b7a2580000

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+7db3bf...@syzkaller.appspotmail.com

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

CPU: 0 PID: 4230 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 : ptrace_request+0xddc/0x1d00 kernel/ptrace.c:1253
lr : ptrace_request+0xdb0/0x1d00 kernel/ptrace.c:1253

sp : ffff80001f957a20
x29: ffff80001f957c90 x28: 0000000000000000 x27: ffff700003f2af4c
x26: dfff800000000000 x25: 00000000fffffff2 x24: ffff0000d61cd1e4
x23: ffff0000d61cd1c0 x22: 0000000000004204 x21: 0000000000000002
x20: ffff0000c8563680 x19: 0000000000000000 x18: 0000000000000000
x17: 0000000000000000 x16: ffff8000081b2c2c x15: 000000000000420f

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:
ptrace_request+0xddc/0x1d00 kernel/ptrace.c:1253
arch_ptrace+0x78/0x94 arch/arm64/kernel/ptrace.c:1794
__do_sys_ptrace kernel/ptrace.c:1328 [inline]
__se_sys_ptrace kernel/ptrace.c:1293 [inline]
__arm64_sys_ptrace+0x1d0/0x5a0 kernel/ptrace.c:1293
__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 9a9f026a d503229f f840095c (2a1903e1)

---[ end trace 2a7fa1216ca6e764 ]---

----------------
Code disassembly (best guess):
0: ea29011f bics xzr, x8, x9
4: 9a9f026a csel x10, x19, xzr, eq // eq = none
8: d503229f csdb
c: f840095c ldtr x28, [x10]
* 10: 2a1903e1 mov w1, w25 <-- trapping instruction


---

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.