[syzbot] [media?] KASAN: slab-out-of-bounds Read in dw210x_op_rw

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 848acc8ffe1b Merge tag 'fsverity-for-linus' of git://git.k..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1655fc9e580000
kernel config: https://syzkaller.appspot.com/x/.config?x=4e38b15c29e6a1d9
dashboard link: https://syzkaller.appspot.com/bug?extid=f408eac9faa61d5a1927
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17167e32580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1427acc6580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9bf3ffd710de/disk-848acc8f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/770c0a63a80c/vmlinux-848acc8f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c54f9393cb03/bzImage-848acc8f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f408ea...@syzkaller.appspotmail.com

dvb-usb: downloading firmware from file 'dvb-usb-dw3101.fw'
dw2102: start downloading DW210X firmware
==================================================================
BUG: KASAN: slab-out-of-bounds in dw210x_op_rw+0xb6/0x180 drivers/media/usb/dvb-usb/dw2102.c:102
Read of size 64 at addr ffff88802bcf2ba0 by task kworker/1:2/803

CPU: 1 UID: 0 PID: 803 Comm: kworker/1:2 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
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description+0x55/0x1e0 mm/kasan/report.c:378
print_report+0x58/0x70 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200
__asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
dw210x_op_rw+0xb6/0x180 drivers/media/usb/dvb-usb/dw2102.c:102
dw2102_load_firmware+0x2b4/0x970 drivers/media/usb/dvb-usb/dw2102.c:1906
dvb_usb_download_firmware+0x1c3/0x270 drivers/media/usb/dvb-usb/dvb-usb-firmware.c:109
dvb_usb_device_init+0xddf/0x2570 drivers/media/usb/dvb-usb/dvb-usb-init.c:298
dw2102_probe+0x8a/0x270 drivers/media/usb/dvb-usb/dw2102.c:2594
usb_probe_interface+0x653/0xc60 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x254/0xae0 drivers/base/dd.c:706
__driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
__device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c4/0x450 drivers/base/dd.c:1098
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
device_add+0x7d7/0xb80 drivers/base/core.c:3772
usb_set_configuration+0x1ad8/0x2180 drivers/usb/core/message.c:2268
usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
usb_probe_device+0x1c3/0x3b0 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x254/0xae0 drivers/base/dd.c:706
__driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
__device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c4/0x450 drivers/base/dd.c:1098
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
device_add+0x7d7/0xb80 drivers/base/core.c:3772
usb_new_device+0x99d/0x1620 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+0x28e8/0x4d30 drivers/usb/core/hub.c:5953
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>

Allocated by task 803:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5334 [inline]
__kmalloc_noprof+0x375/0x720 mm/slub.c:5359
_kmalloc_noprof include/linux/slab.h:992 [inline]
dw2102_load_firmware+0x175/0x970 drivers/media/usb/dvb-usb/dw2102.c:1896
dvb_usb_download_firmware+0x1c3/0x270 drivers/media/usb/dvb-usb/dvb-usb-firmware.c:109
dvb_usb_device_init+0xddf/0x2570 drivers/media/usb/dvb-usb/dvb-usb-init.c:298
dw2102_probe+0x8a/0x270 drivers/media/usb/dvb-usb/dw2102.c:2594
usb_probe_interface+0x653/0xc60 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x254/0xae0 drivers/base/dd.c:706
__driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
__device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c4/0x450 drivers/base/dd.c:1098
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
device_add+0x7d7/0xb80 drivers/base/core.c:3772
usb_set_configuration+0x1ad8/0x2180 drivers/usb/core/message.c:2268
usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
usb_probe_device+0x1c3/0x3b0 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x254/0xae0 drivers/base/dd.c:706
__driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
__device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
bus_for_each_drv+0x258/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c4/0x450 drivers/base/dd.c:1098
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x12a/0x220 drivers/base/bus.c:620
device_add+0x7d7/0xb80 drivers/base/core.c:3772
usb_new_device+0x99d/0x1620 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+0x28e8/0x4d30 drivers/usb/core/hub.c:5953
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88802bcf2ba0
which belongs to the cache kmalloc-16 of size 16
The buggy address is located 0 bytes inside of
allocated 16-byte region [ffff88802bcf2ba0, ffff88802bcf2bb0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802bcf2600 pfn:0x2bcf2
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801b001640 ffff88801b000408 ffffea0000af2d50
raw: ffff88802bcf2600 000000080080007a 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 16259999448, free_ts 0
create_dummy_stack mm/page_owner.c:103 [inline]
register_dummy_stack+0x98/0x100 mm/page_owner.c:109
init_page_owner+0x2e/0x5f0 mm/page_owner.c:127
invoke_init_callbacks mm/page_ext.c:152 [inline]
page_ext_init+0x509/0x550 mm/page_ext.c:490
mm_core_init+0x97/0xb0 mm/mm_init.c:2748
page_owner free stack trace missing

Memory state around the buggy address:
ffff88802bcf2a80: 00 00 fc fc fa fb fc fc 00 01 fc fc 00 01 fc fc
ffff88802bcf2b00: 00 01 fc fc 00 04 fc fc 00 04 fc fc 00 04 fc fc
>ffff88802bcf2b80: 00 04 fc fc 00 00 fc fc 00 00 fc fc fa fb fc fc
^
ffff88802bcf2c00: 00 00 fc fc 00 00 fc fc 00 00 fc fc 00 00 fc fc
ffff88802bcf2c80: 00 00 fc fc fa fb fc fc fa fb fc fc fa fb fc fc
==================================================================


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