From: syzbot <syzbot+2d022f6d27a4d0f2c21a@syzkaller.appspotmail.com>
To: linux-kernel@vger.kernel.org, linux-media@vger.kernel.org,
mchehab@kernel.org, syzkaller-bugs@googlegroups.com
Subject: [syzbot] [media?] KASAN: invalid-free in usb_free_urb
Date: Fri, 21 Aug 2026 21:24:31 -0700 [thread overview]
Message-ID: <6a89247f.dbb3a75c.13dd47.0029.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 4477a78374a5 Add linux-next specific files for 20260814
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=154a6679580000
kernel config: https://syzkaller.appspot.com/x/.config?x=5042554017b3879d
dashboard link: https://syzkaller.appspot.com/bug?extid=2d022f6d27a4d0f2c21a
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d1a5728edb0d/disk-4477a783.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3aebe8202fcd/vmlinux-4477a783.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7e9f7367a2bd/bzImage-4477a783.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2d022f6d27a4d0f2c21a@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: invalid-free in urb_destroy drivers/usb/core/urb.c:25 [inline]
BUG: KASAN: invalid-free in kref_put include/linux/kref.h:65 [inline]
BUG: KASAN: invalid-free in usb_free_urb+0xd0/0x120 drivers/usb/core/urb.c:96
Free of addr ffff888058ab1000 by task kworker/1:1/48
CPU: 1 UID: 0 PID: 48 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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_invalid_free+0xea/0x110 mm/kasan/report.c:557
check_slab_allocation mm/kasan/common.c:-1 [inline]
__kasan_slab_pre_free+0x104/0x120 mm/kasan/common.c:261
kasan_slab_pre_free include/linux/kasan.h:199 [inline]
slab_free_hook mm/slub.c:2693 [inline]
slab_free mm/slub.c:6499 [inline]
kfree+0x173/0x650 mm/slub.c:6792
urb_destroy drivers/usb/core/urb.c:25 [inline]
kref_put include/linux/kref.h:65 [inline]
usb_free_urb+0xd0/0x120 drivers/usb/core/urb.c:96
smsusb_term_device+0x1d0/0x3d0 drivers/media/usb/siano/smsusb.c:352
smsusb_init_device drivers/media/usb/siano/smsusb.c:497 [inline]
smsusb_probe+0x1aba/0x2280 drivers/media/usb/siano/smsusb.c:575
usb_probe_interface+0x788/0xe50 drivers/usb/core/driver.c:399
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:3776
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:293
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:3776
usb_new_device+0x9aa/0x1690 drivers/usb/core/hub.c:2708
hub_port_connect drivers/usb/core/hub.c:5580 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
port_event drivers/usb/core/hub.c:5884 [inline]
hub_event+0x28e8/0x4d30 drivers/usb/core/hub.c:5966
process_one_work kernel/workqueue.c:3387 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
kthread+0x38b/0x480 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 3388:
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:5414 [inline]
__kmalloc_node_track_caller_noprof+0x4b4/0x720 mm/slub.c:5545
kmalloc_reserve net/core/skbuff.c:637 [inline]
__alloc_skb+0x2c1/0x7a0 net/core/skbuff.c:715
alloc_skb include/linux/skbuff.h:1384 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:744 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:801 [inline]
nsim_dev_trap_report_work+0x25f/0xb40 drivers/net/netdevsim/dev.c:847
process_one_work kernel/workqueue.c:3387 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
kthread+0x38b/0x480 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
Freed by task 3388:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2748 [inline]
slab_free mm/slub.c:6499 [inline]
kfree+0x1c5/0x650 mm/slub.c:6792
skb_kfree_head net/core/skbuff.c:1083 [inline]
skb_free_head net/core/skbuff.c:1095 [inline]
skb_release_data+0x85e/0xab0 net/core/skbuff.c:1122
skb_release_all net/core/skbuff.c:1197 [inline]
__kfree_skb+0x5d/0x210 net/core/skbuff.c:1211
nsim_dev_trap_report drivers/net/netdevsim/dev.c:817 [inline]
nsim_dev_trap_report_work+0x7ac/0xb40 drivers/net/netdevsim/dev.c:847
process_one_work kernel/workqueue.c:3387 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
kthread+0x38b/0x480 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 ffff888058ab0000
which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 0 bytes to the right of
4096-byte region [ffff888058ab0000, ffff888058ab1000)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x58ab0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88813ff12140 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88813ff12140 dead000000000100 dead000000000122
head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3388, tgid 3388 (kworker/u8:12), ts 77776651868
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3347 [inline]
allocate_slab+0x7d/0x620 mm/slub.c:3462
new_slab mm/slub.c:3513 [inline]
refill_objects+0x2d5/0x350 mm/slub.c:7410
refill_sheaf mm/slub.c:2885 [inline]
__pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4774
alloc_from_pcs mm/slub.c:4850 [inline]
slab_alloc_node mm/slub.c:4984 [inline]
__do_kmalloc_node mm/slub.c:5413 [inline]
__kmalloc_node_track_caller_noprof+0x548/0x720 mm/slub.c:5545
kmalloc_reserve net/core/skbuff.c:637 [inline]
__alloc_skb+0x2c1/0x7a0 net/core/skbuff.c:715
alloc_skb include/linux/skbuff.h:1384 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:744 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:801 [inline]
nsim_dev_trap_report_work+0x25f/0xb40 drivers/net/netdevsim/dev.c:847
process_one_work kernel/workqueue.c:3387 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
kthread+0x38b/0x480 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
page last free pid 48 tgid 48 ts 77606871666 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_pages_ok+0xb6c/0xc60 mm/page_alloc.c:1596
smscore_unregister_device+0x48a/0x780 drivers/media/common/siano/smscoreapi.c:1228
smsusb_term_device+0x1a0/0x3d0 drivers/media/usb/siano/smsusb.c:349
smsusb_init_device drivers/media/usb/siano/smsusb.c:497 [inline]
smsusb_probe+0x1aba/0x2280 drivers/media/usb/siano/smsusb.c:575
usb_probe_interface+0x788/0xe50 drivers/usb/core/driver.c:399
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:3776
usb_set_configuration+0x1ad8/0x2180 drivers/usb/core/message.c:2268
usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
Memory state around the buggy address:
ffff888058ab0f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888058ab0f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888058ab1000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff888058ab1080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888058ab1100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
---
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reply other threads:[~2026-08-22 4:24 UTC|newest]
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