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BUG: KASAN: invalid-free in f_uac2_opts_p_srate_store+0x1d4/0x260 drivers/usb/gadget/function/f_uac2.c:2087
Free of addr ffff8880293a2bad by task syz.4.2638/21890

CPU: 3 UID: 0 PID: 21890 Comm: syz.4.2638 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
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 lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report_invalid_free+0xb8/0x190 mm/kasan/report.c:557
 check_slab_allocation+0xe1/0xf0 mm/kasan/common.c:230
 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+0x1b6/0x6c0 mm/slub.c:6692
 f_uac2_opts_p_srate_store+0x1d4/0x260 drivers/usb/gadget/function/f_uac2.c:2087
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6ac/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xe7/0x970 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f18fec
Code: Unable to access opcode bytes at 0xf7f18fc2.
RSP: 002b:00000000f53d650c EFLAGS: 00000292 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000080000440
RDX: 000000000000002e RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Allocated by task 21890:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/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+0x331/0x830 mm/slub.c:5471
 __kmemdup_nul mm/util.c:64 [inline]
 kstrdup+0x51/0xe0 mm/util.c:84
 f_uac2_opts_p_srate_store+0x113/0x260 drivers/usb/gadget/function/f_uac2.c:2087
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6ac/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xe7/0x970 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

The buggy address belongs to the object at ffff8880293a2b80
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 45 bytes inside of
 47-byte region [ffff8880293a2b80, ffff8880293a2baf)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880293a2200 pfn:0x293a2
flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000200 ffff88801bc428c0 ffffea000000e710 ffffea00004d3b50
raw: ffff8880293a2200 000000080020001d 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 20520, tgid 20519 (syz.6.2468), ts 713504003499, free_ts 709467523659
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
 __alloc_pages_slowpath mm/page_alloc.c:4821 [inline]
 __alloc_frozen_pages_noprof+0x6ab/0x2dc0 mm/page_alloc.c:5317
 alloc_slab_page mm/slub.c:3266 [inline]
 allocate_slab mm/slub.c:3380 [inline]
 new_slab+0xa2/0x640 mm/slub.c:3426
 ___slab_alloc+0x5d1/0x800 mm/slub.c:4463
 slab_alloc_node mm/slub.c:4908 [inline]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kvmalloc_node_noprof+0x4fe/0x970 mm/slub.c:6905
 alloc_shrinker_info+0xf0/0x470 mm/shrinker.c:94
 mem_cgroup_css_online+0xa4/0xbf0 mm/memcontrol.c:4222
 online_css+0xb2/0x350 kernel/cgroup/cgroup.c:5772
 css_create kernel/cgroup/cgroup.c:5850 [inline]
 cgroup_apply_control_enable+0xa8d/0xdd0 kernel/cgroup/cgroup.c:3385
 cgroup_mkdir+0x57f/0x1330 kernel/cgroup/cgroup.c:6051
 kernfs_iop_mkdir+0x111/0x190 fs/kernfs/dir.c:1305
 vfs_mkdir+0x361/0x850 fs/namei.c:5276
 filename_mkdirat+0x48b/0x5e0 fs/namei.c:5309
 __do_sys_mkdirat fs/namei.c:5330 [inline]
 __se_sys_mkdirat fs/namei.c:5327 [inline]
 __ia32_sys_mkdirat+0x88/0xc0 fs/namei.c:5327
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xe7/0x970 arch/x86/entry/syscall_32.c:307
page last free pid 19921 tgid 19921 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 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]
 __do_kmalloc_node mm/slub.c:5333 [inline]
 __kmalloc_noprof+0x2bf/0x820 mm/slub.c:5359
 _kmalloc_noprof include/linux/slab.h:992 [inline]
 _kzalloc_noprof include/linux/slab.h:1309 [inline]
 fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x14c/0xad0 net/ipv6/route.c:3833
 ip6_route_add+0x4b/0x1d0 net/ipv6/route.c:3962
 addrconf_prefix_route+0x2fb/0x510 net/ipv6/addrconf.c:2504
 inet6_addr_add+0x575/0x9a0 net/ipv6/addrconf.c:3076
 inet6_rtm_newaddr+0x1475/0x1bb0 net/ipv6/addrconf.c:5094
 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x48b/0x4e0 net/socket.c:2252

Memory state around the buggy address:
 ffff8880293a2a80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
 ffff8880293a2b00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
>ffff8880293a2b80: 00 00 00 00 00 07 fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff8880293a2c00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
 ffff8880293a2c80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
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