================================================================== 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 ffff888102bd04b0 by task syz.4.1021/4615 CPU: 1 PID: 4615 Comm: syz.4.1021 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+0x908/0xce0 fs/seq_file.c:272 proc_reg_read_iter+0x1be/0x290 fs/proc/inode.c:310 call_read_iter include/linux/fs.h:2066 [inline] new_sync_read fs/read_write.c:415 [inline] vfs_read+0x62a/0xa50 fs/read_write.c:496 ksys_read+0x14a/0x260 fs/read_write.c:634 __do_sys_read fs/read_write.c:644 [inline] __se_sys_read fs/read_write.c:642 [inline] __x64_sys_read+0x7b/0x90 fs/read_write.c:642 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f08023c8159 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:00007f0800e21028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f080264ffa0 RCX: 00007f08023c8159 RDX: 0000000000002020 RSI: 0000200000006400 RDI: 0000000000000004 RBP: 00007f080245f06b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0802650038 R14: 00007f080264ffa0 R15: 00007ffe9b4a9dc8 Allocated by task 300: 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 get_bMaxPacketSize0+0xc0/0x6b0 drivers/usb/core/hub.c:4781 hub_port_init+0xa63/0x2520 drivers/usb/core/hub.c:4983 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 Freed by task 300: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:362 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370 kasan_slab_free include/linux/kasan.h:220 [inline] slab_free_hook mm/slub.c:1600 [inline] slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1626 slab_free mm/slub.c:3208 [inline] kfree+0xc0/0x270 mm/slub.c:4196 usb_control_msg+0x2d5/0x3f0 drivers/usb/core/message.c:172 get_bMaxPacketSize0+0xc0/0x6b0 drivers/usb/core/hub.c:4781 hub_port_init+0xa63/0x2520 drivers/usb/core/hub.c:4983 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 ffff888102bd04b0 which belongs to the cache kmalloc-8 of size 8 The buggy address is located 0 bytes inside of 8-byte region [ffff888102bd04b0, ffff888102bd04b8) The buggy address belongs to the page: page:ffffea00040af400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x102bd0 flags: 0x4000000000000200(slab) raw: 4000000000000200 ffffea000468ff40 0000000200000002 ffff888100043c80 raw: 0000000000000000 0000000000660066 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 2134999423, 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 kvasprintf_const+0xd7/0x240 lib/kasprintf.c:-1 kobject_set_name_vargs+0x61/0x110 lib/kobject.c:297 kobject_add_varg lib/kobject.c:392 [inline] kobject_init_and_add+0xeb/0x190 lib/kobject.c:481 sysfs_slab_add+0x89/0x2a0 mm/slub.c:5610 slab_sysfs_init+0x61/0x15e mm/slub.c:5695 do_one_initcall+0x205/0x5e0 init/main.c:1172 do_initcall_level+0x174/0x2dc init/main.c:1245 do_initcalls+0x50/0x92 init/main.c:1261 page_owner free stack trace missing Memory state around the buggy address: ffff888102bd0380: fc fc fc fa fc fc fc fc fa fc fc fc fc 00 fc fc ffff888102bd0400: fc fc fa fc fc fc fc fa fc fc fc fc 00 fc fc fc >ffff888102bd0480: fc 00 fc fc fc fc fa fc fc fc fc 00 fc fc fc fc ^ ffff888102bd0500: fa fc fc fc fc fa fc fc fc fc fa fc fc fc fc fa ffff888102bd0580: fc fc fc fc 00 fc fc fc fc 00 fc fc fc fc fa fc ================================================================== xt_CT: netfilter: NOTRACK target is deprecated, use CT instead or upgrade iptables