[v5.15] Internal error in sys_sendfile64

[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=1104b2f0580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=7c6c20e8446a79ce5925
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+7c6c20...@syzkaller.appspotmail.com

Internal error: Oops - BTI: 0000000036000001 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 4756 Comm: syz.2.202 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 : __do_sys_sendfile64 fs/read_write.c:1312 [inline]
pc : __se_sys_sendfile64 fs/read_write.c:1303 [inline]
pc : __arm64_sys_sendfile64+0x2f8/0x3b0 fs/read_write.c:1303
lr : __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:239 [inline]
lr : __do_sys_sendfile64 fs/read_write.c:1312 [inline]
lr : __se_sys_sendfile64 fs/read_write.c:1303 [inline]
lr : __arm64_sys_sendfile64+0x2d8/0x3b0 fs/read_write.c:1303
sp : ffff80001fea7ca0
x29: ffff80001fea7d20 x28: 0000000020000040 x27: 1ffff00003fd4f98
x26: dfff800000000000 x25: 0000000000000000 x24: ffff80001fea7cc0
x23: 0000000000001000 x22: ffff0000cb540000 x21: 0000000000000001
x20: 0000000000000001 x19: 00000000fffffff2 x18: 0000000000000000
x17: ffff800016d04000 x16: ffff8000088dc3f0 x15: ffff8000088dc328
x14: ffff8000088e0498 x13: 1ffff0000282e06b x12: 0000000000080000
x11: 0000000000009ae4 x10: ffff80002428b000 x9 : 0000000020000040
x8 : 0000000000000001 x7 : ffff800008750ed4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
__do_sys_sendfile64 fs/read_write.c:1312 [inline]
__se_sys_sendfile64 fs/read_write.c:1303 [inline]
__arm64_sys_sendfile64+0x2f8/0x3b0 fs/read_write.c:1303
__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: 2a1f03f3 2a1f03e0 f94023e8 f8000928 (2a1303e1)
---[ end trace d1e245c30e6c4dcc ]---
----------------
Code disassembly (best guess):
0: 2a1f03f3 mov w19, wzr
4: 2a1f03e0 mov w0, wzr
8: f94023e8 ldr x8, [sp, #64]
c: f8000928 sttr x8, [x9]
* 10: 2a1303e1 mov w1, w19 <-- 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=130779a2580000

kernel config: https://syzkaller.appspot.com/x/.config?x=9e47345638b85bd0
dashboard link: https://syzkaller.appspot.com/bug?extid=7c6c20e8446a79ce5925
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=13990af0580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=159d7434580000

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+7c6c20...@syzkaller.appspotmail.com

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

CPU: 1 PID: 4240 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 : __do_sys_sendfile64 fs/read_write.c:1312 [inline]
pc : __se_sys_sendfile64 fs/read_write.c:1303 [inline]
pc : __arm64_sys_sendfile64+0x2f8/0x3b0 fs/read_write.c:1303
lr : __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:239 [inline]
lr : __do_sys_sendfile64 fs/read_write.c:1312 [inline]
lr : __se_sys_sendfile64 fs/read_write.c:1303 [inline]
lr : __arm64_sys_sendfile64+0x2d8/0x3b0 fs/read_write.c:1303

sp : ffff80001fa57ca0
x29: ffff80001fa57d20 x28: 0000000020000000 x27: 1ffff00003f4af98
x26: dfff800000000000 x25: 0000000000000000 x24: ffff80001fa57cc0
x23: 000000000000db37 x22: ffff0000d7699b40 x21: 0000000000000001
x20: fffffffffffffff7 x19: 00000000fffffff2 x18: 0000000000000000
x17: 0000000000000000 x16: ffff8000088dc3f0 x15: 0000000020000000
x14: 0000000000000000 x13: 1ffff0000282e06b x12: 0000000000ff0100
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000020000000
x8 : 0000000000000000 x7 : ffff800008750ed4 x6 : 0000000000000000

x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000001
x2 : 0000000000000008 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
__do_sys_sendfile64 fs/read_write.c:1312 [inline]
__se_sys_sendfile64 fs/read_write.c:1303 [inline]
__arm64_sys_sendfile64+0x2f8/0x3b0 fs/read_write.c:1303
__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: 2a1f03f3 2a1f03e0 f94023e8 f8000928 (2a1303e1)

---[ end trace 13555ec55cf0d56c ]---

----------------
Code disassembly (best guess):
0: 2a1f03f3 mov w19, wzr
4: 2a1f03e0 mov w0, wzr
8: f94023e8 ldr x8, [sp, #64]
c: f8000928 sttr x8, [x9]
* 10: 2a1303e1 mov w1, w19 <-- trapping instruction


---

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