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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 ffff8880124b9109 by task syz.0.0/5310

CPU: 0 UID: 0 PID: 5310 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_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:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fca4739e0d9
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:00007fca481b0fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fca47625fa0 RCX: 00007fca4739e0d9
RDX: 000000000000001d RSI: 0000200000000540 RDI: 0000000000000009
RBP: 00007fca47435024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fca47626038 R14: 00007fca47625fa0 R15: 00007ffe3da35d88
 </TASK>

Allocated by task 5310:
 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_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: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 ffff8880124b9100
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 9 bytes inside of
 29-byte region [ffff8880124b9100, ffff8880124b911d)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x124b9
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801b041780 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800400040 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5100, tgid 5100 (rm), ts 58290929122
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0x2209/0x2280 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x217/0x5a0 mm/page_alloc.c:5436
 alloc_slab_page mm/slub.c:3267 [inline]
 allocate_slab+0x7c/0x5e0 mm/slub.c:3382
 new_slab mm/slub.c:3428 [inline]
 refill_objects+0x2d5/0x350 mm/slub.c:7305
 refill_sheaf mm/slub.c:2805 [inline]
 __pcs_replace_empty_main+0x2c3/0x6b0 mm/slub.c:4677
 alloc_from_pcs mm/slub.c:4775 [inline]
 slab_alloc_node mm/slub.c:4907 [inline]
 __kmalloc_cache_noprof+0x3ab/0x660 mm/slub.c:5480
 _kmalloc_noprof include/linux/slab.h:988 [inline]
 slab_free_hook mm/slub.c:2630 [inline]
 slab_free mm/slub.c:6372 [inline]
 kmem_cache_free+0x156/0x650 mm/slub.c:6499
 tear_down_vmas+0x31f/0x530 mm/mmap.c:1277
 exit_mmap+0x4ca/0x9f0 mm/mmap.c:1335
 __mmput+0x118/0x420 kernel/fork.c:1193
 exec_mm_put_old fs/exec.c:916 [inline]
 setup_new_exec+0x30d/0x360 fs/exec.c:1377
 load_elf_binary+0xbc0/0x28d0 fs/binfmt_elf.c:1024
 search_binary_handler fs/exec.c:1756 [inline]
 exec_binprm fs/exec.c:1788 [inline]
 bprm_execve+0x930/0x1590 fs/exec.c:1844
 do_execveat_common+0x4f4/0x670 fs/exec.c:1942
 __do_sys_execve fs/exec.c:2015 [inline]
 __se_sys_execve fs/exec.c:2009 [inline]
 __x64_sys_execve+0x97/0xc0 fs/exec.c:2009
page last free pid 5100 tgid 5100 ts 58290836379 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_batch_list_free mm/mmu_gather.c:161 [inline]
 tlb_finish_mmu+0x13e/0x220 mm/mmu_gather.c:552
 exit_mmap+0x4b2/0x9f0 mm/mmap.c:1328
 __mmput+0x118/0x420 kernel/fork.c:1193
 exec_mm_put_old fs/exec.c:916 [inline]
 setup_new_exec+0x30d/0x360 fs/exec.c:1377
 load_elf_binary+0xbc0/0x28d0 fs/binfmt_elf.c:1024
 search_binary_handler fs/exec.c:1756 [inline]
 exec_binprm fs/exec.c:1788 [inline]
 bprm_execve+0x930/0x1590 fs/exec.c:1844
 do_execveat_common+0x4f4/0x670 fs/exec.c:1942
 __do_sys_execve fs/exec.c:2015 [inline]
 __se_sys_execve fs/exec.c:2009 [inline]
 __x64_sys_execve+0x97/0xc0 fs/exec.c:2009
 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:
 ffff8880124b9000: 00 00 00 fc fc fc fc fc 00 00 00 00 fc fc fc fc
 ffff8880124b9080: fa fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
>ffff8880124b9100: 00 00 00 05 fc fc fc fc 00 00 00 fc fc fc fc fc
                      ^
 ffff8880124b9180: 00 00 00 00 fc fc fc fc 00 00 00 00 fc fc fc fc
 ffff8880124b9200: fa fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
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