From: syzbot <syzbot+ccffdf05833ebdaeae70@syzkaller.appspotmail.com>
To: linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org,
linux-usb@vger.kernel.org, maximlevitsky@gmail.com,
oakad@yahoo.com, syzkaller-bugs@googlegroups.com,
ulf.hansson@linaro.org, ulfh@kernel.org
Subject: [syzbot] [mmc?] KASAN: slab-use-after-free Write in ms_read_bytes
Date: Tue, 22 Sep 2026 17:33:23 -0700 [thread overview]
Message-ID: <6ab31e53.3179f8cd.1e36b2.002e.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: d58dffe9ee2c USB: core: amend usb_get_from_anchor() kernel..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
console output: https://syzkaller.appspot.com/x/log.txt?x=112d0515580000
kernel config: https://syzkaller.appspot.com/x/.config?x=c451f9f64434b622
dashboard link: https://syzkaller.appspot.com/bug?extid=ccffdf05833ebdaeae70
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/424c61cbb872/disk-d58dffe9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4124586dc97c/vmlinux-d58dffe9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a07e8e384dc4/bzImage-d58dffe9.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ccffdf05833ebdaeae70@syzkaller.appspotmail.com
=========
==================================================================
BUG: KASAN: slab-use-after-free in ms_read_bytes+0x8fe/0x990 drivers/memstick/host/rtsx_usb_ms.c:450
Write of size 1 at addr ffff88813c188079 by task kworker/1:5/5239
CPU: 1 UID: 0 PID: 5239 Comm: kworker/1:5 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events rtsx_usb_ms_handle_req
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
ms_read_bytes+0x8fe/0x990 drivers/memstick/host/rtsx_usb_ms.c:450
rtsx_usb_ms_issue_cmd drivers/memstick/host/rtsx_usb_ms.c:477 [inline]
rtsx_usb_ms_handle_req+0x557/0x1a00 drivers/memstick/host/rtsx_usb_ms.c:531
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x69f/0xc90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Allocated by task 1662:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x2d8/0x680 mm/slub.c:5563
_kmalloc_noprof include/linux/slab.h:991 [inline]
_kzalloc_noprof include/linux/slab.h:1312 [inline]
memstick_alloc_card drivers/memstick/core/memstick.c:383 [inline]
memstick_check+0x2c1/0x10d0 drivers/memstick/core/memstick.c:452
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x69f/0xc90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Freed by task 1662:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x43/0x70 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+0x20c/0x650 mm/slub.c:6792
memstick_alloc_card drivers/memstick/core/memstick.c:420 [inline]
memstick_check+0x72b/0x10d0 drivers/memstick/core/memstick.c:452
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x69f/0xc90 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 ffff88813c188000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 121 bytes inside of
freed 2048-byte region [ffff88813c188000, ffff88813c188800)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x13c188
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff888100042000 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 0200000000000040 ffff888100042000 dead000000000100 dead000000000122
head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 0200000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 24, tgid 24 (kworker/1:0), ts 137296809400
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0xf4b/0x3440 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2d7/0x2f70 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3347 [inline]
allocate_slab mm/slub.c:3462 [inline]
new_slab+0xa9/0x6e0 mm/slub.c:3513
refill_objects+0xe3/0x410 mm/slub.c:7410
refill_sheaf mm/slub.c:2885 [inline]
__pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
alloc_from_pcs mm/slub.c:4850 [inline]
slab_alloc_node mm/slub.c:4984 [inline]
__kmalloc_cache_noprof+0x4a1/0x680 mm/slub.c:5559
_kmalloc_noprof include/linux/slab.h:991 [inline]
_kzalloc_noprof include/linux/slab.h:1312 [inline]
usb_alloc_dev+0x55/0x1090 drivers/usb/core/usb.c:651
hub_port_connect drivers/usb/core/hub.c:5483 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
port_event drivers/usb/core/hub.c:5884 [inline]
hub_event+0x2c5d/0x4510 drivers/usb/core/hub.c:5966
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x69f/0xc90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page_owner free stack trace missing
Memory state around the buggy address:
ffff88813c187f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88813c187f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88813c188000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88813c188080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88813c188100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
---
This report is generated by a bot. It may contain errors.
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next reply other threads:[~2026-09-23 0:33 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-23 0:33 syzbot [this message]
[not found] <CALq3yPV0NNZAO4pARgPe3_f-m2oFJH1FEKx-JsX7gc0s80jBQg@mail.gmail.com>
2026-09-24 19:21 ` syzbot
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