fuse: Bad value for 'fd'
==================================================================
BUG: KASAN: invalid-free in f_uac2_opts_c_srate_store+0x225/0x2b0 drivers/usb/gadget/function/f_uac2.c:2091
Free of addr ffff8880124f2ba6 by task syz.0.0/5325

CPU: 0 UID: 0 PID: 5325 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 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_invalid_free+0xea/0x110 mm/kasan/report.c:557
 check_slab_allocation mm/kasan/common.c:-1 [inline]
 __kasan_slab_pre_free+0x104/0x120 mm/kasan/common.c:261
 kasan_slab_pre_free include/linux/kasan.h:199 [inline]
 slab_free_hook mm/slub.c:2623 [inline]
 slab_free mm/slub.c:6372 [inline]
 kfree+0x173/0x640 mm/slub.c:6687
 f_uac2_opts_c_srate_store+0x225/0x2b0 drivers/usb/gadget/function/f_uac2.c:2091
 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: 0033:0x7f1a85d9e0d9
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:00007f1a86beefe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f1a86025fa0 RCX: 00007f1a85d9e0d9
RDX: 0000000000000088 RSI: 0000200000000340 RDI: 0000000000000004
RBP: 00007f1a85e35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a86026038 R14: 00007f1a86025fa0 R15: 00007fff61cea8c8
 </TASK>

Allocated by task 5325:
 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:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5337 [inline]
 __kmalloc_node_track_caller_noprof+0x4c7/0x740 mm/slub.c:5466
 __kmemdup_nul mm/util.c:64 [inline]
 kstrdup+0x42/0x100 mm/util.c:84
 f_uac2_opts_c_srate_store+0x11f/0x2b0 drivers/usb/gadget/function/f_uac2.c:2091
 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 ffff8880124f2ba0
 which belongs to the cache kmalloc-16 of size 16
The buggy address is located 6 bytes inside of
 12-byte region [ffff8880124f2ba0, ffff8880124f2bac)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x124f2
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801b041640 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800800080 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 9, tgid 9 (kworker/0:0), ts 94434688686
 create_dummy_stack mm/page_owner.c:121 [inline]
 register_dummy_stack+0x98/0x100 mm/page_owner.c:127
 init_page_owner+0x2e/0x600 mm/page_owner.c:145
 invoke_init_callbacks mm/page_ext.c:152 [inline]
 page_ext_init+0x511/0x550 mm/page_ext.c:490
 mm_core_init+0x97/0xb0 mm/mm_init.c:2685
page last free pid 15 tgid 15 ts 94410272176 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962
 __tlb_remove_table_free mm/mmu_gather.c:228 [inline]
 tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:291
 rcu_do_batch kernel/rcu/tree.c:2645 [inline]
 rcu_core+0x794/0x10b0 kernel/rcu/tree.c:2897
 handle_softirqs+0x226/0x860 kernel/softirq.c:645
 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1108
 smpboot_thread_fn+0x565/0xa70 kernel/smpboot.c:160
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff8880124f2a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880124f2b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880124f2b80: fc fc fc fc 00 04 fc fc 00 00 fc fc 00 00 fc fc
                               ^
 ffff8880124f2c00: fa fb fc fc fa fb fc fc fa fb fc fc 00 00 fc fc
 ffff8880124f2c80: 00 00 fc fc 00 00 fc fc 00 00 fc fc fa fb fc fc
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