[v5.15] Internal error in sys_sched_setattr

[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=16b3d1a2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=83d678981a7be74bfb68
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+83d678...@syzkaller.appspotmail.com

Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4322 Comm: syz.1.72 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 : sched_copy_attr kernel/sched/core.c:-1 [inline]
pc : __do_sys_sched_setattr kernel/sched/core.c:7819 [inline]
pc : __se_sys_sched_setattr kernel/sched/core.c:7809 [inline]
pc : __arm64_sys_sched_setattr+0x218/0x6bc kernel/sched/core.c:7809
lr : sched_copy_attr kernel/sched/core.c:7761 [inline]
lr : __do_sys_sched_setattr kernel/sched/core.c:7819 [inline]
lr : __se_sys_sched_setattr kernel/sched/core.c:7809 [inline]
lr : __arm64_sys_sched_setattr+0x1ac/0x6bc kernel/sched/core.c:7809
sp : ffff800020037c60
x29: ffff800020037d20 x28: 1fffe00019dce004 x27: 0000000020000040
x26: 0000000020000040 x25: dfff800000000000 x24: ffff700004006f90
x23: 0000000000000042 x22: ffff0000cee70024 x21: 0000000000000000
x20: ffff800020037ca0 x19: ffff0000cee70000 x18: 0000000000000000
x17: 0000000000000000 x16: ffff80000823abb4 x15: 0000000000000000
x14: 0000000000000000 x13: 1ffff0000282e06b x12: 0000000000080000
x11: 000000000000019a x10: 0000000020000040 x9 : 0000000000000038
x8 : 00000000fffffff2 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : ffff80001131c340 x0 : 0000000000000001
Call trace:
sched_copy_attr kernel/sched/core.c:7761 [inline]
__do_sys_sched_setattr kernel/sched/core.c:7819 [inline]
__se_sys_sched_setattr kernel/sched/core.c:7809 [inline]
__arm64_sys_sched_setattr+0x218/0x6bc kernel/sched/core.c:7809
__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: 9a9f034a d503229f 52800709 b8000949 (128000c8)
---[ end trace 6129485f9ffac4b0 ]---
----------------
Code disassembly (best guess):
0: 9a9f034a csel x10, x26, xzr, eq // eq = none
4: d503229f csdb
8: 52800709 mov w9, #0x38 // #56
c: b8000949 sttr w9, [x10]
* 10: 128000c8 mov w8, #0xfffffff9 // #-7 <-- 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=112605a2580000

kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=83d678981a7be74bfb68
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=11b28af0580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13e469a2580000

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+83d678...@syzkaller.appspotmail.com

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

CPU: 0 PID: 4226 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 : sched_copy_attr kernel/sched/core.c:7732 [inline]

pc : __do_sys_sched_setattr kernel/sched/core.c:7819 [inline]
pc : __se_sys_sched_setattr kernel/sched/core.c:7809 [inline]

pc : __arm64_sys_sched_setattr+0x17c/0x6bc kernel/sched/core.c:7809
lr : sched_copy_attr kernel/sched/core.c:7731 [inline]

lr : __do_sys_sched_setattr kernel/sched/core.c:7819 [inline]
lr : __se_sys_sched_setattr kernel/sched/core.c:7809 [inline]

lr : __arm64_sys_sched_setattr+0x100/0x6bc kernel/sched/core.c:7809
sp : ffff80001f9c7c60
x29: ffff80001f9c7d20 x28: 1fffe0001b2126d4 x27: 0000000020000280
x26: 0000000020000280 x25: dfff800000000000 x24: ffff700003f38f90
x23: 0000002000028000 x22: ffff0000d90936a4 x21: 0000000000000000
x20: ffff80001f9c7ca0 x19: ffff0000d9093680 x18: 0000000000000000
x17: 0000000000000000 x16: ffff80000823ab18 x15: 0000000000000000
x14: 0000000000000000 x13: 1ffff0000282e06b x12: 0000000000ff0100
x11: 0000000000000000 x10: 0000000020000280 x9 : 0000000000000000

x8 : 00000000fffffff2 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001

x2 : 0000000000000008 x1 : ffff80001131c340 x0 : 0000000000000000
Call trace:
sched_copy_attr kernel/sched/core.c:7731 [inline]

__do_sys_sched_setattr kernel/sched/core.c:7819 [inline]
__se_sys_sched_setattr kernel/sched/core.c:7809 [inline]

__arm64_sys_sched_setattr+0x17c/0x6bc kernel/sched/core.c:7809

__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: ea29037f 9a9f034a d503229f b8400949 (350008e8)
---[ end trace bede6ce1161f86fa ]---

----------------
Code disassembly (best guess):

0: ea29037f bics xzr, x27, x9
4: 9a9f034a csel x10, x26, xzr, eq // eq = none
8: d503229f csdb
c: b8400949 ldtr w9, [x10]
* 10: 350008e8 cbnz w8, 0x12c <-- trapping instruction


---
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