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BUG: KASAN: invalid-free in f_uac2_opts_p_srate_store+0x225/0x2b0 drivers/usb/gadget/function/f_uac2.c:2087
Free of addr ffff88800078fc07 by task syz.0.0/5326

CPU: 0 UID: 0 PID: 5326 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:2622 [inline]
 slab_free mm/slub.c:6377 [inline]
 kfree+0x173/0x640 mm/slub.c:6692
 f_uac2_opts_p_srate_store+0x225/0x2b0 drivers/usb/gadget/function/f_uac2.c:2087
 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:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f94fb39e0d9
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:00007f94fc290fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f94fb625fa0 RCX: 00007f94fb39e0d9
RDX: 0000000000000028 RSI: 0000200000000040 RDI: 0000000000000005
RBP: 00007f94fb435024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f94fb626038 R14: 00007f94fb625fa0 R15: 00007ffeea50c728
 </TASK>

Allocated by task 5326:
 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:5334 [inline]
 __kmalloc_node_track_caller_noprof+0x4c3/0x730 mm/slub.c:5471
 __kmemdup_nul mm/util.c:64 [inline]
 kstrdup+0x42/0x100 mm/util.c:84
 f_uac2_opts_p_srate_store+0x11f/0x2b0 drivers/usb/gadget/function/f_uac2.c:2087
 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:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88800078fc00
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 7 bytes inside of
 41-byte region [ffff88800078fc00, ffff88800078fc29)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x78f
flags: 0x7ff00000000000(node=0|zone=0|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 007ff00000000000 ffff88801b0418c0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800200020 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 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 5288, tgid 5288 (syz-executor), ts 84940876731, free_ts 71313825291
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946
 __alloc_pages_slowpath+0x383/0xcc0 mm/page_alloc.c:4821
 __alloc_frozen_pages_noprof+0x31f/0x380 mm/page_alloc.c:5317
 alloc_slab_page mm/slub.c:3266 [inline]
 allocate_slab+0x79/0x5e0 mm/slub.c:3380
 new_slab mm/slub.c:3426 [inline]
 ___slab_alloc+0x16a/0x950 mm/slub.c:4463
 __slab_alloc_node mm/slub.c:4527 [inline]
 slab_alloc_node mm/slub.c:4908 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_flags_noprof+0x347/0x800 mm/slub.c:5528
 _kmalloc_flags_noprof mm/slab.h:39 [inline]
 alloc_slab_obj_exts+0x4d/0x170 mm/slub.c:2149
 __memcg_slab_post_alloc_hook+0x5d3/0xf10 mm/memcontrol.c:3587
 memcg_slab_post_alloc_hook mm/slub.c:2447 [inline]
 slab_post_alloc_hook mm/slub.c:4603 [inline]
 slab_alloc_node mm/slub.c:4917 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kvmalloc_node_noprof+0x61c/0x860 mm/slub.c:6905
 xt_alloc_table_info+0x40/0xb0 net/netfilter/x_tables.c:1286
 ipt_register_table+0xcd/0x310 net/ipv4/netfilter/ip_tables.c:1733
 iptable_security_table_init+0x41/0x70 net/ipv4/netfilter/iptable_security.c:46
 xt_find_table_lock+0x311/0x400 net/netfilter/x_tables.c:1353
 xt_request_find_table_lock+0x26/0x100 net/netfilter/x_tables.c:1378
 get_info net/ipv4/netfilter/ip_tables.c:961 [inline]
 do_ipt_get_ctl+0x77f/0x1300 net/ipv4/netfilter/ip_tables.c:1660
page last free pid 5225 tgid 5225 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0xc1e/0xd10 mm/page_alloc.c:2950
 __slab_free+0x274/0x2c0 mm/slub.c:5741
 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:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4584 [inline]
 slab_alloc_node mm/slub.c:4917 [inline]
 kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4931
 ptlock_alloc+0x20/0x70 mm/memory.c:7531
 ptlock_init include/linux/mm.h:3775 [inline]
 pagetable_pte_ctor include/linux/mm.h:3824 [inline]
 __pte_alloc_one_noprof include/asm-generic/pgalloc.h:79 [inline]
 pte_alloc_one+0x7a/0x370 arch/x86/mm/pgtable.c:18
 do_fault_around mm/memory.c:5812 [inline]
 do_read_fault mm/memory.c:5851 [inline]
 do_fault mm/memory.c:5994 [inline]
 do_pte_missing+0x13c8/0x34b0 mm/memory.c:4566
 handle_pte_fault mm/memory.c:6379 [inline]
 __handle_mm_fault mm/memory.c:6517 [inline]
 handle_mm_fault+0x1b36/0x3080 mm/memory.c:6686
 do_user_addr_fault+0xa4d/0x1340 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595

Memory state around the buggy address:
 ffff88800078fb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88800078fb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88800078fc00: 00 00 00 00 00 01 fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88800078fc80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88800078fd00: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
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