[syzbot] [usb?] general protection fault in request_ihex_firmware

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3b5f4b83c4ab Merge tag 'for-7.2-rc5-tag' of git://git.kern..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=154005c1580000
kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782
dashboard link: https://syzkaller.appspot.com/bug?extid=cb67625c47fe4d6dd7c8
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=104192a9580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=113df8c6580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f99ca00b02a2/disk-3b5f4b83.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5caff5208bfc/vmlinux-3b5f4b83.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c0e941f5f816/bzImage-3b5f4b83.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+cb6762...@syzkaller.appspotmail.com

usb 1-1: New USB device found, idVendor=086a, idProduct=0100, bcdDevice= 0.01
usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
emi26 - firmware loader 1-1:1.0: emi26_probe start
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 24 Comm: kworker/1:0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:ihex_validate_fw include/linux/ihex.h:56 [inline]
RIP: 0010:request_ihex_firmware.constprop.0+0x11e/0x250 include/linux/ihex.h:74
Code: 48 89 04 24 e8 13 11 b8 00 4c 39 24 24 0f 82 94 00 00 00 e8 04 11 b8 00 49 8d 7c 24 04 48 89 f8 48 89 fe 48 c1 e8 03 83 e6 07 <42> 8a 0c 38 49 8d 44 24 05 48 89 c2 48 c1 ea 03 40 38 f1 40 0f 9e
RSP: 0018:ffffc900001e6ec8 EFLAGS: 00010202
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff81524ec7
RDX: ffff88801f2a0000 RSI: 0000000000000004 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88802be73980 R14: ffffc900001e6fe8 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888123edc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbca99eb580 CR3: 0000000072d5e000 CR4: 00000000003526f0
Call Trace:
<TASK>
emi26_load_firmware drivers/usb/misc/emi26.c:86 [inline]
emi26_probe+0x13c/0xe30 drivers/usb/misc/emi26.c:232
usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
__device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x64/0x160 drivers/base/bus.c:620
device_add+0x121d/0x1970 drivers/base/core.c:3772
usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
__device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x64/0x160 drivers/base/bus.c:620
device_add+0x121d/0x1970 drivers/base/core.c:3772
usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695
hub_port_connect drivers/usb/core/hub.c:5567 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x30a3/0x4a60 drivers/usb/core/hub.c:5953
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ihex_validate_fw include/linux/ihex.h:56 [inline]
RIP: 0010:request_ihex_firmware.constprop.0+0x11e/0x250 include/linux/ihex.h:74
Code: 48 89 04 24 e8 13 11 b8 00 4c 39 24 24 0f 82 94 00 00 00 e8 04 11 b8 00 49 8d 7c 24 04 48 89 f8 48 89 fe 48 c1 e8 03 83 e6 07 <42> 8a 0c 38 49 8d 44 24 05 48 89 c2 48 c1 ea 03 40 38 f1 40 0f 9e
RSP: 0018:ffffc900001e6ec8 EFLAGS: 00010202
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff81524ec7
RDX: ffff88801f2a0000 RSI: 0000000000000004 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88802be73980 R14: ffffc900001e6fe8 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888123edc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbca99eb580 CR3: 000000007e506000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
0: 48 89 04 24 mov %rax,(%rsp)
4: e8 13 11 b8 00 call 0xb8111c
9: 4c 39 24 24 cmp %r12,(%rsp)
d: 0f 82 94 00 00 00 jb 0xa7
13: e8 04 11 b8 00 call 0xb8111c
18: 49 8d 7c 24 04 lea 0x4(%r12),%rdi
1d: 48 89 f8 mov %rdi,%rax
20: 48 89 fe mov %rdi,%rsi
23: 48 c1 e8 03 shr $0x3,%rax
27: 83 e6 07 and $0x7,%esi
* 2a: 42 8a 0c 38 mov (%rax,%r15,1),%cl <-- trapping instruction
2e: 49 8d 44 24 05 lea 0x5(%r12),%rax
33: 48 89 c2 mov %rax,%rdx
36: 48 c1 ea 03 shr $0x3,%rdx
3a: 40 38 f1 cmp %sil,%cl
3d: 40 rex
3e: 0f .byte 0xf
3f: 9e sahf


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