KASAN: invalid-free in dev_set_name

Status: upstream: reported on 2026/08/06 22:30
Reported-by: syzbot+6d70675ca53c6c740269@syzkaller.appspotmail.com
First crash: 12d, last: 10d

Sample crash report:
configfs-gadget gadget: uvc: uvc_function_bind()
==================================================================
BUG: KASAN: double-free or invalid-free in slab_free mm/slub.c:3504 [inline]
BUG: KASAN: double-free or invalid-free in kfree+0xef/0x2a0 mm/slub.c:4564

CPU: 1 PID: 8804 Comm: syz.0.1202 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 kasan_report_invalid_free+0x3a/0x70 mm/kasan/report.c:373
 ____kasan_slab_free+0xf3/0x110 mm/kasan/common.c:-1
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1710 [inline]
 slab_free_freelist_hook+0xec/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 kobject_set_name_vargs+0xc6/0x110 lib/kobject.c:317
 dev_set_name+0xdf/0x130 drivers/base/core.c:3200
 __video_register_device+0x354e/0x4450 drivers/media/v4l2-core/v4l2-dev.c:1036
 video_register_device include/media/v4l2-dev.h:384 [inline]
 uvc_register_video+0x22f/0x2d0 drivers/usb/gadget/function/f_uvc.c:450
 uvc_function_bind+0xcde/0x12d0 drivers/usb/gadget/function/f_uvc.c:773
 usb_add_function+0x2d9/0x980 drivers/usb/gadget/composite.c:324
 configfs_composite_bind+0xa02/0xf60 drivers/usb/gadget/configfs.c:1417
 udc_bind_to_driver+0x203/0x5f0 drivers/usb/gadget/udc/core.c:1574
 usb_gadget_probe_driver+0x1fb/0x380 drivers/usb/gadget/udc/core.c:1637
 gadget_dev_desc_UDC_store+0x1ba/0x2e0 drivers/usb/gadget/configfs.c:289
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x30b/0x400 fs/configfs/file.c:229
 call_write_iter include/linux/fs.h:2173 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x748/0xd70 fs/read_write.c:594
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f11808af0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f117eb07028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f1180b36fa0 RCX: 00007f11808af0d9
RDX: 000000000000000c RSI: 00002000000005c0 RDI: 0000000000000004
RBP: 00007f1180946024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1180b37038 R14: 00007f1180b36fa0 R15: 00007ffebf53a278
 </TASK>

Allocated by task 6009:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc+0xaf/0xe0 mm/kasan/common.c:522
 kvasprintf+0xe3/0x1a0 lib/kasprintf.c:25
 kobject_set_name_vargs+0x5d/0x110 lib/kobject.c:297
 dev_set_name+0xdf/0x130 drivers/base/core.c:3200
 __video_register_device+0x354e/0x4450 drivers/media/v4l2-core/v4l2-dev.c:1036
 video_register_device include/media/v4l2-dev.h:384 [inline]
 uvc_register_video+0x22f/0x2d0 drivers/usb/gadget/function/f_uvc.c:450
 uvc_function_bind+0xcde/0x12d0 drivers/usb/gadget/function/f_uvc.c:773
 usb_add_function+0x2d9/0x980 drivers/usb/gadget/composite.c:324
 configfs_composite_bind+0xa02/0xf60 drivers/usb/gadget/configfs.c:1417
 udc_bind_to_driver+0x203/0x5f0 drivers/usb/gadget/udc/core.c:1574
 usb_gadget_probe_driver+0x1fb/0x380 drivers/usb/gadget/udc/core.c:1637
 gadget_dev_desc_UDC_store+0x1ba/0x2e0 drivers/usb/gadget/configfs.c:289
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x30b/0x400 fs/configfs/file.c:229
 call_write_iter include/linux/fs.h:2173 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x748/0xd70 fs/read_write.c:594
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff888146c81118
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes inside of
 8-byte region [ffff888146c81118, ffff888146c81120)
The buggy address belongs to the page:
page:ffffea00051b2040 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888146c81118 pfn:0x146c81
flags: 0x57ff00000000200(slab|node=1|zone=2|lastcpupid=0x7ff)
raw: 057ff00000000200 ffffea000521b648 ffffea0005076488 ffff888016c41280
raw: ffff888146c81118 0000000000660036 00000001ffffffff 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 1, ts 5970737195, free_ts 0
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x24f6/0x2670 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2031
 alloc_slab_page mm/slub.c:1780 [inline]
 allocate_slab mm/slub.c:1917 [inline]
 new_slab+0xc0/0x4b0 mm/slub.c:1980
 ___slab_alloc+0x807/0xdd0 mm/slub.c:3013
 __slab_alloc mm/slub.c:3100 [inline]
 slab_alloc_node mm/slub.c:3191 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 __kmalloc_track_caller+0x11b/0x330 mm/slub.c:4930
 kstrdup mm/util.c:60 [inline]
 kstrdup_const+0x51/0x90 mm/util.c:83
 __kernfs_new_node+0xa8/0x6b0 fs/kernfs/dir.c:589
 kernfs_new_node+0x148/0x250 fs/kernfs/dir.c:669
 kernfs_create_dir_ns+0x40/0x120 fs/kernfs/dir.c:1005
 sysfs_create_dir_ns+0x12c/0x290 fs/sysfs/dir.c:59
 create_dir lib/kobject.c:89 [inline]
 kobject_add_internal+0x5ba/0xcd0 lib/kobject.c:263
 kobject_add_varg lib/kobject.c:398 [inline]
 kobject_init_and_add+0x128/0x190 lib/kobject.c:481
 bus_add_driver+0x1de/0x5d0 drivers/base/bus.c:613
 driver_register+0x32d/0x430 drivers/base/driver.c:240
 acpi_ac_init+0xfb/0x160 drivers/acpi/ac.c:362
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888146c81000: 03 fc fc fc fc 07 fc fc fc fc 07 fc fc fc fc 07
 ffff888146c81080: fc fc fc fc 07 fc fc fc fc 07 fc fc fc fc fb fc
>ffff888146c81100: fc fc fc fb fc fc fc fc fb fc fc fc fc 07 fc fc
                            ^
 ffff888146c81180: fc fc 07 fc fc fc fc 07 fc fc fc fc 00 fc fc fc
 ffff888146c81200: fc 00 fc fc fc fc 00 fc fc fc fc 06 fc fc fc fc
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/08 08:41 linux-5.15.y aabd761612db 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: invalid-free in dev_set_name
2026/08/08 08:41 linux-5.15.y aabd761612db 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: invalid-free in dev_set_name
2026/08/06 22:30 linux-5.15.y 9c7634c60784 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: invalid-free in dev_set_name
* Struck through repros no longer work on HEAD.