[v5.15] Internal error in prctl_set_mm

[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=131732f0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=ef1a6da085aa7b1445b1
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+ef1a6d...@syzkaller.appspotmail.com

Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4438 Comm: syz.2.105 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 : prctl_set_mm+0x3e4/0xdf8 kernel/sys.c:2137
lr : sign_extend64 include/linux/bitops.h:183 [inline]
lr : __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:244 [inline]
lr : prctl_set_mm_map kernel/sys.c:1991 [inline]
lr : prctl_set_mm+0x3c0/0xdf8 kernel/sys.c:2137
sp : ffff80001fcf78c0
x29: ffff80001fcf7c60 x28: 00000000fffffff2 x27: ffff80001fcf79e0
x26: dfff800000000000 x25: ffff700003f9ef3c x24: 0000000000000000
x23: ffff0000d3263680 x22: ffff80001fcf7a90 x21: 000000000000000f
x20: 0000000000000000 x19: 0000000000000001 x18: 0000000000000000
x17: 0000000000000002 x16: ffff8000081e12b0 x15: 000000000000003d
x14: 0000000000ff0100 x13: 1ffff0000282e06b x12: 0000000000080000
x11: 0000000000000131 x10: 0000000000000000 x9 : 0000ffffffffffff
x8 : 0000000000000068 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
prctl_set_mm_map kernel/sys.c:1991 [inline]
prctl_set_mm+0x3e4/0xdf8 kernel/sys.c:2137
__do_sys_prctl kernel/sys.c:2442 [inline]
__se_sys_prctl kernel/sys.c:2298 [inline]
__arm64_sys_prctl+0x758/0xf14 kernel/sys.c:2298
__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: 9a9f028a d503229f 52800d08 b8000948 (17ffff42)
---[ end trace e16b4fd8e11c0c6d ]---
----------------
Code disassembly (best guess):
0: 9a9f028a csel x10, x20, xzr, eq // eq = none
4: d503229f csdb
8: 52800d08 mov w8, #0x68 // #104
c: b8000948 sttr w8, [x10]
* 10: 17ffff42 b 0xfffffffffffffd18 <-- 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=15ce71a2580000

kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=ef1a6da085aa7b1445b1
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=10d8c9a2580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13ce71a2580000

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+ef1a6d...@syzkaller.appspotmail.com

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

CPU: 1 PID: 4221 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 : prctl_set_mm+0x3e4/0xdf8 kernel/sys.c:2137
lr : sign_extend64 include/linux/bitops.h:183 [inline]
lr : __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:244 [inline]
lr : prctl_set_mm_map kernel/sys.c:1991 [inline]
lr : prctl_set_mm+0x3c0/0xdf8 kernel/sys.c:2137

sp : ffff80001fe778c0
x29: ffff80001fe77c60 x28: 00000000fffffff2 x27: ffff80001fe779e0
x26: dfff800000000000 x25: ffff700003fcef3c x24: 0000000000000000
x23: ffff0000d1021b40 x22: ffff80001fe77a90 x21: 000000000000000f

x20: 0000000000000000 x19: 0000000000000001 x18: 0000000000000000

x17: 0000000000000000 x16: ffff8000081e12b0 x15: 000000000000003d
x14: 0000000000ff0100 x13: 1ffff0000282e06b x12: 0000000000ff0100
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000ffffffffffff

x8 : 0000000000000068 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
prctl_set_mm_map kernel/sys.c:1991 [inline]
prctl_set_mm+0x3e4/0xdf8 kernel/sys.c:2137
__do_sys_prctl kernel/sys.c:2442 [inline]
__se_sys_prctl kernel/sys.c:2298 [inline]
__arm64_sys_prctl+0x758/0xf14 kernel/sys.c:2298
__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: 9a9f028a d503229f 52800d08 b8000948 (17ffff42)

---[ end trace 11c7a3fd33bd5e74 ]---

----------------
Code disassembly (best guess):
0: 9a9f028a csel x10, x20, xzr, eq // eq = none
4: d503229f csdb
8: 52800d08 mov w8, #0x68 // #104
c: b8000948 sttr w8, [x10]
* 10: 17ffff42 b 0xfffffffffffffd18 <-- trapping instruction


---

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