================================================================== BUG: KASAN: use-after-free in string_nocheck lib/vsprintf.c:641 [inline] BUG: KASAN: use-after-free in string+0x20f/0x2a0 lib/vsprintf.c:723 Read of size 1 at addr ffff888104793de8 by task syz.5.683/3134 CPU: 1 PID: 3134 Comm: syz.5.683 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x1a7/0x208 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0x100/0x140 mm/kasan/report.c:452 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306 string_nocheck lib/vsprintf.c:641 [inline] string+0x20f/0x2a0 lib/vsprintf.c:723 vsnprintf+0xec5/0x1990 lib/vsprintf.c:2689 seq_vprintf fs/seq_file.c:398 [inline] seq_printf+0x185/0x280 fs/seq_file.c:413 show_interrupts+0x921/0xa90 kernel/irq/proc.c:526 seq_read_iter+0x472/0xce0 fs/seq_file.c:230 proc_reg_read_iter+0x1be/0x290 fs/proc/inode.c:310 do_iter_readv_writev+0x477/0x5f0 fs/read_write.c:-1 do_iter_read+0x168/0x5d0 fs/read_write.c:801 vfs_readv fs/read_write.c:921 [inline] do_preadv+0x233/0x390 fs/read_write.c:1013 __do_sys_preadv fs/read_write.c:1063 [inline] __se_sys_preadv fs/read_write.c:1058 [inline] __x64_sys_preadv+0x9e/0xb0 fs/read_write.c:1058 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f72d8b5b1d9 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:00007f72d7593028 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00007f72d8de3090 RCX: 00007f72d8b5b1d9 RDX: 0000000000000001 RSI: 0000200000000180 RDI: 0000000000000001 RBP: 00007f72d8bf2888 R08: 0000000080000002 R09: 0000000000000000 R10: 0000000000000076 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f72d8de3128 R14: 00007f72d8de3090 R15: 00007ffecf368458 Allocated by task 15: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] ____kasan_kmalloc mm/kasan/common.c:509 [inline] __kasan_kmalloc+0xd4/0x100 mm/kasan/common.c:518 kasan_kmalloc include/linux/kasan.h:254 [inline] kmem_cache_alloc_trace+0x179/0x2e0 mm/slub.c:2979 kmalloc include/linux/slab.h:555 [inline] usb_control_msg+0x74/0x3f0 drivers/usb/core/message.c:156 set_port_feature drivers/usb/core/hub.c:454 [inline] hub_port_reset+0x2fb/0x1720 drivers/usb/core/hub.c:3025 hub_port_init+0xae7/0x2520 drivers/usb/core/hub.c:4992 hub_port_connect drivers/usb/core/hub.c:5433 [inline] hub_port_connect_change drivers/usb/core/hub.c:5644 [inline] port_event drivers/usb/core/hub.c:5810 [inline] hub_event+0x23b1/0x4220 drivers/usb/core/hub.c:5892 process_one_work+0x6fd/0xbc0 kernel/workqueue.c:2301 worker_thread+0xa8e/0x13c0 kernel/workqueue.c:2447 kthread+0x324/0x3b0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff888104793de8 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 0 bytes inside of 8-byte region [ffff888104793de8, ffff888104793df0) The buggy address belongs to the page: page:ffffea000411e4c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888104793168 pfn:0x104793 flags: 0x4000000000000200(slab) raw: 4000000000000200 ffffea00041779c8 ffffea000413e908 ffff888100043c80 raw: ffff888104793168 000000000066003e 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 16, ts 1656708623, free_ts 0 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x176/0x190 mm/page_alloc.c:2462 get_page_from_freelist+0x225f/0x23f0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x29a/0x640 mm/page_alloc.c:5384 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1813 [inline] new_slab+0x84/0x3f0 mm/slub.c:1874 new_slab_objects mm/slub.c:2632 [inline] ___slab_alloc+0x2f8/0x4c0 mm/slub.c:2796 __slab_alloc+0x63/0xa0 mm/slub.c:2836 slab_alloc_node mm/slub.c:2918 [inline] slab_alloc mm/slub.c:2960 [inline] __kmalloc_track_caller+0x1e4/0x310 mm/slub.c:4541 kstrdup mm/util.c:63 [inline] kstrdup_const+0x55/0x90 mm/util.c:86 __kernfs_new_node+0xa6/0x670 fs/kernfs/dir.c:658 kernfs_new_node+0x150/0x260 fs/kernfs/dir.c:739 kernfs_create_dir_ns+0x47/0x130 fs/kernfs/dir.c:1087 sysfs_create_dir_ns+0x128/0x290 fs/sysfs/dir.c:59 create_dir lib/kobject.c:89 [inline] kobject_add_internal+0x774/0xde0 lib/kobject.c:263 kobject_add_varg lib/kobject.c:398 [inline] kobject_add+0x165/0x230 lib/kobject.c:450 device_add+0x3d8/0xc00 drivers/base/core.c:3206 device_create_groups_vargs drivers/base/core.c:3960 [inline] device_create+0x26c/0x300 drivers/base/core.c:4002 page_owner free stack trace missing Memory state around the buggy address: ffff888104793c80: 00 fc fc fc fc fb fc fc fc fc 00 fc fc fc fc 00 ffff888104793d00: fc fc fc fc fb fc fc fc fc 00 fc fc fc fc 00 fc >ffff888104793d80: fc fc fc fb fc fc fc fc 00 fc fc fc fc fb fc fc ^ ffff888104793e00: fc fc fb fc fc fc fc 00 fc fc fc fc 00 fc fc fc ffff888104793e80: fc 00 fc fc fc fc fb fc fc fc fc 00 fc fc fc fc ==================================================================