==================================================================
BUG: KASAN: invalid-free in f_uac2_opts_c_srate_store+0x224/0x2b0 drivers/usb/gadget/function/f_uac2.c:2091
Free of addr ffff888121894fc6 by task syz.4.412/1572

CPU: 1 UID: 0 PID: 1572 Comm: syz.4.412 Not tainted syzkaller #0 89da86cd63dd77ed75a7a6b832383be384370f21
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 print_address_description+0x71/0x210 mm/kasan/report.c:377
 print_report+0x4a/0x70 mm/kasan/report.c:481
 kasan_report_invalid_free+0x11e/0x160 mm/kasan/report.c:556
 check_slab_allocation+0xdf/0xf0 include/linux/page-flags.h:-1
 __kasan_slab_pre_free+0x36/0x50 mm/kasan/common.c:257
 kasan_slab_pre_free include/linux/kasan.h:199 [inline]
 slab_free_hook mm/slub.c:2390 [inline]
 slab_free mm/slub.c:4714 [inline]
 kfree+0xf8/0x440 mm/slub.c:4875
 f_uac2_opts_c_srate_store+0x224/0x2b0 drivers/usb/gadget/function/f_uac2.c:2091
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x32f/0x490 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x762/0xfd0 fs/read_write.c:684
 ksys_write+0x145/0x260 fs/read_write.c:737
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x7f/0x90 fs/read_write.c:746
 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f854519e019
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:00007f85460ac028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8545425fa0 RCX: 00007f854519e019
RDX: 0000000000000014 RSI: 0000200000000d80 RDI: 0000000000000004
RBP: 00007f854523500c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8545426038 R14: 00007f8545425fa0 R15: 00007ffe6089c0f8
 </TASK>

Allocated by task 1572:
 kasan_save_stack mm/kasan/common.c:49 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:70
 kasan_save_alloc_info+0x3a/0x50 mm/kasan/generic.c:565
 poison_kmalloc_redzone mm/kasan/common.c:379 [inline]
 __kasan_kmalloc+0x96/0xb0 mm/kasan/common.c:396
 kasan_kmalloc include/linux/kasan.h:261 [inline]
 __do_kmalloc_node mm/slub.c:4395 [inline]
 __kmalloc_node_track_caller_noprof+0x24e/0x4f0 mm/slub.c:4414
 kstrdup+0x4d/0x130 mm/util.c:70
 f_uac2_opts_c_srate_store+0x11e/0x2b0 drivers/usb/gadget/function/f_uac2.c:2091
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x32f/0x490 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x762/0xfd0 fs/read_write.c:684
 ksys_write+0x145/0x260 fs/read_write.c:737
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x7f/0x90 fs/read_write.c:746
 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

The buggy address belongs to the object at ffff888121894fc0
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 6 bytes inside of
 19-byte region [ffff888121894fc0, ffff888121894fd3)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x121894
flags: 0x4000000000000000(zone=1)
page_type: f5(slab)
raw: 4000000000000000 ffff888100041780 dead000000000100 dead000000000122
raw: 0000000000000000 0000000080400040 00000001f5000000 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 0x52800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP), pid 243, tgid 243 (dhcpcd-run-hook), ts 17293343675, free_ts 17293166456
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook+0x37d/0x3b0 mm/page_alloc.c:1863
 prep_new_page+0x2d/0x180 mm/page_alloc.c:1871
 get_page_from_freelist+0x4aea/0x4ba0 mm/page_alloc.c:3948
 __alloc_pages_noprof+0x35a/0x7e0 mm/page_alloc.c:5315
 alloc_slab_page+0x6b/0x1e0 mm/slub.c:-1
 allocate_slab+0x69/0x430 mm/slub.c:2687
 new_slab mm/slub.c:2741 [inline]
 ___slab_alloc+0x591/0x8c0 mm/slub.c:3934
 __slab_alloc mm/slub.c:4025 [inline]
 __slab_alloc_node mm/slub.c:4078 [inline]
 slab_alloc_node mm/slub.c:4239 [inline]
 __kmalloc_cache_noprof+0x2cd/0x470 mm/slub.c:4421
 kmalloc_noprof include/linux/slab.h:881 [inline]
 slab_free_hook mm/slub.c:2397 [inline]
 slab_free mm/slub.c:4714 [inline]
 kmem_cache_free+0x18d/0x4f0 mm/slub.c:4825
 vm_area_free+0xee/0x140 kernel/fork.c:523
 remove_vma+0x1a5/0x1d0 mm/vma.c:342
 exit_mmap+0x547/0xc20 mm/mmap.c:1995
 __mmput+0x92/0x330 kernel/fork.c:1370
 mmput+0x55/0x170 kernel/fork.c:1394
 exit_mm kernel/exit.c:575 [inline]
 do_exit+0x9a5/0x2850 kernel/exit.c:942
 do_group_exit+0x21f/0x2f0 kernel/exit.c:1098
page last free pid 243 tgid 243 stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1390 [inline]
 free_unref_page+0xbb8/0xf70 mm/page_alloc.c:2876
 __free_pages+0x6b/0x3b0 mm/page_alloc.c:5402
 free_pages+0x86/0x90 mm/page_alloc.c:5415
 tlb_batch_list_free mm/mmu_gather.c:160 [inline]
 tlb_finish_mmu+0x117/0x1d0 mm/mmu_gather.c:524
 exit_mmap+0x458/0xc20 mm/mmap.c:1983
 __mmput+0x92/0x330 kernel/fork.c:1370
 mmput+0x55/0x170 kernel/fork.c:1394
 exit_mm kernel/exit.c:575 [inline]
 do_exit+0x9a5/0x2850 kernel/exit.c:942
 do_group_exit+0x21f/0x2f0 kernel/exit.c:1098
 __do_sys_exit_group kernel/exit.c:1109 [inline]
 __se_sys_exit_group kernel/exit.c:1107 [inline]
 __x64_sys_exit_group+0x43/0x50 kernel/exit.c:1107
 x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Memory state around the buggy address:
 ffff888121894e80: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
 ffff888121894f00: 00 00 00 00 fc fc fc fc fa fb fb fb fc fc fc fc
>ffff888121894f80: fa fb fb fb fc fc fc fc 00 00 03 fc fc fc fc fc
                                           ^
 ffff888121895000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888121895080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
UDC core: g1: couldn't find an available UDC or it's busy