From: syzbot <syzbot+596b59aea1a9deaaab67@syzkaller.appspotmail.com>
To: dakr@kernel.org, driver-core@lists.linux.dev,
gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
rafael@kernel.org, syzkaller-bugs@googlegroups.com
Subject: [syzbot] [kernel?] KASAN: slab-use-after-free Read in raw_process_ep_io (2)
Date: Tue, 28 Jul 2026 20:25:25 -0700 [thread overview]
Message-ID: <6a6972a5.d9e86bb5.297b12.004f.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: d326f83e819c Merge tag 'net-7.2-rc5' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=118d5ca9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d69870d5e052935f
dashboard link: https://syzkaller.appspot.com/bug?extid=596b59aea1a9deaaab67
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/b579ac560ac6/disk-d326f83e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f1d14922156b/vmlinux-d326f83e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5cca8ce9b203/bzImage-d326f83e.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+596b59aea1a9deaaab67@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:648 [inline]
BUG: KASAN: slab-use-after-free in string+0x471/0x4d0 lib/vsprintf.c:730
Read of size 1 at addr ffff888034f293e0 by task syz.0.210/6386
CPU: 0 UID: 0 PID: 6386 Comm: syz.0.210 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
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
string_nocheck lib/vsprintf.c:648 [inline]
string+0x471/0x4d0 lib/vsprintf.c:730
vsnprintf+0x422/0x1300 lib/vsprintf.c:2945
snprintf+0xc7/0x100 lib/vsprintf.c:3043
set_dev_info drivers/base/core.c:4984 [inline]
dev_vprintk_emit+0x375/0x3e0 drivers/base/core.c:4994
dev_printk_emit+0xd2/0x10d drivers/base/core.c:5007
__dev_printk+0xcb/0x100 drivers/base/core.c:5019
_dev_err+0xef/0x127 drivers/base/core.c:5062
raw_process_ep_io.cold+0x43/0x83 drivers/usb/gadget/legacy/raw_gadget.c:1116
raw_ioctl_ep_write drivers/usb/gadget/legacy/raw_gadget.c:1153 [inline]
raw_ioctl+0x25a/0x2b80 drivers/usb/gadget/legacy/raw_gadget.c:1325
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5831b9db2b
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007f5832aadf60 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f5831b9db2b
RDX: 00007f5832aadfe0 RSI: 0000000040085507 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007f5831f50320 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 0000200000002340
R13: 000000000000000a R14: 00007f5831e25fa0 R15: 00007ffd1da71278
</TASK>
Allocated by task 6384:
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+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5362 [inline]
__kmalloc_node_track_caller_noprof+0x331/0x830 mm/slub.c:5497
kvasprintf+0xbc/0x150 lib/kasprintf.c:25
kvasprintf_const+0x66/0x1a0 lib/kasprintf.c:49
kobject_set_name_vargs+0x5a/0x140 lib/kobject.c:274
dev_set_name+0xc7/0x100 drivers/base/core.c:3560
usb_add_gadget+0x520/0x920 drivers/usb/gadget/udc/core.c:1459
usb_add_gadget_udc_release drivers/usb/gadget/udc/core.c:1517 [inline]
usb_add_gadget_udc+0x26/0x70 drivers/usb/gadget/udc/core.c:1564
dummy_udc_probe+0x69e/0x960 drivers/usb/gadget/udc/dummy_hcd.c:1103
platform_probe+0x106/0x1d0 drivers/base/platform.c:1439
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
device_driver_attach+0xd1/0x220 drivers/base/dd.c:1203
bind_store+0xf4/0x190 drivers/base/bus.c:267
drv_attr_store+0x74/0xb0 drivers/base/bus.c:125
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6ac/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 6412:
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+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2705 [inline]
slab_free mm/slub.c:6405 [inline]
kfree+0x22b/0x6c0 mm/slub.c:6720
kfree_const+0x5a/0x70 mm/util.c:46
kobject_cleanup lib/kobject.c:695 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x218/0x640 lib/kobject.c:737
put_device+0x1f/0x30 drivers/base/core.c:3880
platform_remove+0x5f/0x80 drivers/base/platform.c:1456
device_remove+0xcb/0x180 drivers/base/dd.c:616
__device_release_driver drivers/base/dd.c:1349 [inline]
device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
unbind_store+0xf8/0x110 drivers/base/bus.c:244
drv_attr_store+0x74/0xb0 drivers/base/bus.c:125
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6ac/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff888034f293e0
which belongs to the cache kmalloc-16 of size 16
The buggy address is located 0 bytes inside of
freed 16-byte region [ffff888034f293e0, ffff888034f293f0)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888034f29b80 pfn:0x34f29
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88813fe22640 ffffea00015409d0 ffffea00007fb6d0
raw: ffff888034f29b80 000000080080007b 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 5610, tgid 5610 (syz-executor), ts 101676951155, free_ts 101676872118
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
prep_new_page mm/page_alloc.c:1867 [inline]
get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
alloc_slab_page mm/slub.c:3294 [inline]
allocate_slab mm/slub.c:3408 [inline]
new_slab+0xa2/0x650 mm/slub.c:3454
refill_objects+0xe3/0x410 mm/slub.c:7338
refill_sheaf mm/slub.c:2832 [inline]
__pcs_replace_empty_main+0x376/0x680 mm/slub.c:4703
alloc_from_pcs mm/slub.c:4801 [inline]
slab_alloc_node mm/slub.c:4933 [inline]
__do_kmalloc_node mm/slub.c:5361 [inline]
__kvmalloc_node_noprof+0x793/0x970 mm/slub.c:6933
xt_jumpstack_alloc net/netfilter/x_tables.c:1449 [inline]
do_replace_table+0x1c5/0x760 net/netfilter/x_tables.c:1486
xt_replace_table+0x2e/0x130 net/netfilter/x_tables.c:1545
__do_replace+0x1cf/0x980 net/ipv4/netfilter/ip_tables.c:1062
do_replace net/ipv4/netfilter/ip_tables.c:1139 [inline]
do_ipt_set_ctl+0xa53/0xcf0 net/ipv4/netfilter/ip_tables.c:1634
nf_setsockopt+0x8d/0xf0 net/netfilter/nf_sockopt.c:101
ip_setsockopt+0xcb/0xf0 net/ipv4/ip_sockglue.c:1424
tcp_setsockopt+0xa7/0x100 net/ipv4/tcp.c:4179
do_sock_setsockopt+0xf3/0x1d0 net/socket.c:2368
__sys_setsockopt+0x195/0x220 net/socket.c:2393
page last free pid 5610 tgid 5610 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1406 [inline]
__free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
___free_pages_bulk mm/kasan/shadow.c:333 [inline]
__kasan_populate_vmalloc_do mm/kasan/shadow.c:385 [inline]
__kasan_populate_vmalloc+0x164/0x210 mm/kasan/shadow.c:424
kasan_populate_vmalloc include/linux/kasan.h:580 [inline]
alloc_vmap_area+0x95d/0x2bb0 mm/vmalloc.c:2123
__get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3226
__vmalloc_node_range_noprof+0x228/0x1630 mm/vmalloc.c:4042
__vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4143
xt_counters_alloc+0x4c/0x70 net/netfilter/x_tables.c:1474
__do_replace+0x97/0x980 net/ipv4/netfilter/ip_tables.c:1044
do_replace net/ipv4/netfilter/ip_tables.c:1139 [inline]
do_ipt_set_ctl+0xa53/0xcf0 net/ipv4/netfilter/ip_tables.c:1634
nf_setsockopt+0x8d/0xf0 net/netfilter/nf_sockopt.c:101
ip_setsockopt+0xcb/0xf0 net/ipv4/ip_sockglue.c:1424
tcp_setsockopt+0xa7/0x100 net/ipv4/tcp.c:4179
do_sock_setsockopt+0xf3/0x1d0 net/socket.c:2368
__sys_setsockopt+0x195/0x220 net/socket.c:2393
__do_sys_setsockopt net/socket.c:2399 [inline]
__se_sys_setsockopt net/socket.c:2396 [inline]
__x64_sys_setsockopt+0xbd/0x160 net/socket.c:2396
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
Memory state around the buggy address:
ffff888034f29280: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc
ffff888034f29300: fa fb fc fc fa fb fc fc 00 05 fc fc fa fb fc fc
>ffff888034f29380: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc
^
ffff888034f29400: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc
ffff888034f29480: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc
==================================================================
---
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reply other threads:[~2026-07-29 3:25 UTC|newest]
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