================================================================== BUG: KASAN: slab-use-after-free in printer_req_free drivers/usb/gadget/function/f_printer.c:258 [inline] BUG: KASAN: slab-use-after-free in printer_func_unbind+0x2e6/0x6d0 drivers/usb/gadget/function/f_printer.c:1466 Read of size 8 at addr ffff8880296bd118 by task syz.2.616/7240 CPU: 1 UID: 0 PID: 7240 Comm: syz.2.616 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 printer_req_free drivers/usb/gadget/function/f_printer.c:258 [inline] printer_func_unbind+0x2e6/0x6d0 drivers/usb/gadget/function/f_printer.c:1466 purge_configs_funcs+0x248/0x3d0 drivers/usb/gadget/configfs.c:1600 configfs_composite_unbind+0xa4/0x1c0 drivers/usb/gadget/configfs.c:1846 gadget_unbind_driver+0x1cb/0x410 drivers/usb/gadget/udc/core.c:1725 device_remove drivers/base/dd.c:616 [inline] __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x48b/0x880 drivers/base/dd.c:1372 driver_detach+0x1f3/0x2d0 drivers/base/dd.c:1435 bus_remove_driver+0x226/0x320 drivers/base/bus.c:840 usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1785 unregister_gadget drivers/usb/gadget/configfs.c:263 [inline] gadget_dev_desc_UDC_store+0x17a/0x2f0 drivers/usb/gadget/configfs.c:290 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x337/0x430 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f59e279e159 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:00007f59e3592028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f59e2a26090 RCX: 00007f59e279e159 RDX: 0000000000000001 RSI: 0000200000000600 RDI: 0000000000000008 RBP: 00007f59e283506b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f59e2a26128 R14: 00007f59e2a26090 R15: 00007ffc1dedacb8 Allocated by task 6200: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:409 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x600 mm/slub.c:5680 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] dummy_alloc_request+0x7f/0x130 drivers/usb/gadget/udc/dummy_hcd.c:695 usb_ep_alloc_request+0x67/0x280 drivers/usb/gadget/udc/core.c:198 printer_req_alloc drivers/usb/gadget/function/f_printer.c:240 [inline] printer_func_bind+0x55c/0xbc0 drivers/usb/gadget/function/f_printer.c:1150 usb_add_function+0x2e1/0x9f0 drivers/usb/gadget/composite.c:333 configfs_composite_bind+0xde0/0x1410 drivers/usb/gadget/configfs.c:1802 gadget_bind_driver+0x2ca/0x9e0 drivers/usb/gadget/udc/core.c:1663 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x254/0xae0 drivers/base/dd.c:706 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898 __driver_attach+0x339/0x600 drivers/base/dd.c:1292 bus_for_each_dev+0x23b/0x2c0 drivers/base/bus.c:386 bus_add_driver+0x38f/0x6e0 drivers/base/bus.c:771 driver_register+0x23a/0x320 drivers/base/driver.c:174 usb_gadget_register_driver_owner+0xf9/0x270 drivers/usb/gadget/udc/core.c:1753 gadget_dev_desc_UDC_store+0x1c9/0x2f0 drivers/usb/gadget/configfs.c:300 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x337/0x430 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 7189: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:264 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2780 [inline] slab_free mm/slub.c:6630 [inline] kfree+0x1c5/0x650 mm/slub.c:6923 printer_req_free drivers/usb/gadget/function/f_printer.c:259 [inline] printer_func_unbind+0x2fa/0x6d0 drivers/usb/gadget/function/f_printer.c:1466 purge_configs_funcs+0x248/0x3d0 drivers/usb/gadget/configfs.c:1600 configfs_composite_unbind+0xa4/0x1c0 drivers/usb/gadget/configfs.c:1846 gadget_unbind_driver+0x1cb/0x410 drivers/usb/gadget/udc/core.c:1725 device_remove drivers/base/dd.c:616 [inline] __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x48b/0x880 drivers/base/dd.c:1372 driver_detach+0x1f3/0x2d0 drivers/base/dd.c:1435 bus_remove_driver+0x226/0x320 drivers/base/bus.c:840 usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1785 unregister_gadget drivers/usb/gadget/configfs.c:263 [inline] gadget_dev_desc_UDC_store+0x17a/0x2f0 drivers/usb/gadget/configfs.c:290 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x337/0x430 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880296bd100 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 24 bytes inside of freed 128-byte region [ffff8880296bd100, ffff8880296bd180) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x296bd flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88813ff24a00 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 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 5619, tgid 5619 (udevd), ts 84314665292 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1854 prep_new_page mm/page_alloc.c:1862 [inline] get_page_from_freelist+0x220f/0x2280 mm/page_alloc.c:3933 __alloc_frozen_pages_noprof+0x1fc/0x400 mm/page_alloc.c:5471 alloc_slab_page mm/slub.c:3384 [inline] allocate_slab+0x7d/0x5e0 mm/slub.c:3499 new_slab mm/slub.c:3550 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7539 refill_sheaf mm/slub.c:2917 [inline] __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4811 alloc_from_pcs mm/slub.c:4887 [inline] slab_alloc_node mm/slub.c:5021 [inline] __kmalloc_cache_noprof+0x396/0x600 mm/slub.c:5676 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] kernfs_get_open_node fs/kernfs/file.c:537 [inline] kernfs_fop_open+0x6f6/0xd20 fs/kernfs/file.c:725 do_dentry_open+0x80e/0x1360 fs/open.c:1000 vfs_open_consume+0x4a/0x350 fs/open.c:1131 do_open fs/namei.c:4846 [inline] path_openat+0x14a6/0x1da0 fs/namei.c:5011 do_file_open+0x23e/0x4a0 fs/namei.c:5040 do_sys_openat2+0x115/0x200 fs/open.c:1442 do_sys_open fs/open.c:1448 [inline] __do_sys_openat fs/open.c:1464 [inline] __se_sys_openat fs/open.c:1459 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1459 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5621 tgid 5621 ts 84277760799 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1401 [inline] __free_frozen_pages+0xc97/0xd90 mm/page_alloc.c:2952 __slab_free+0x269/0x2c0 mm/slub.c:5926 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:361 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4720 [inline] slab_alloc_node mm/slub.c:5033 [inline] kmem_cache_alloc_lru_noprof+0x29e/0x5f0 mm/slub.c:5066 sock_alloc_inode+0x2c/0x1a0 net/socket.c:330 alloc_inode+0x6a/0x1b0 fs/inode.c:339 new_inode_pseudo include/linux/fs.h:3044 [inline] sock_alloc net/socket.c:710 [inline] __sock_create+0x127/0xac0 net/socket.c:1643 sock_create net/socket.c:1737 [inline] __sys_socket_create net/socket.c:1774 [inline] __sys_socket+0xd6/0x1b0 net/socket.c:1821 __do_sys_socket net/socket.c:1835 [inline] __se_sys_socket net/socket.c:1833 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1833 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8880296bd000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880296bd080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880296bd100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880296bd180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880296bd200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================