R13: 00007ffd6ca0e80f R14: 00007f7e68b8c9c0 R15: 000000000119bf8c
kobject_add_internal failed for 9p-fcall-cache (error: -12 parent: slab)
==================================================================
BUG: KASAN: double-free or invalid-free in slab_free mm/slub.c:3051 [inline]
BUG: KASAN: double-free or invalid-free in kmem_cache_free+0xac/0x610 mm/slub.c:3067

CPU: 1 PID: 7396 Comm: syz-executor.1 Not tainted 5.4.87-syzkaller-00101-g47494776db44 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1dd/0x24e lib/dump_stack.c:118
 print_address_description+0x96/0x640 mm/kasan/report.c:374
 kasan_report_invalid_free+0x54/0xc0 mm/kasan/report.c:468
 __kasan_slab_free+0x102/0x230 mm/kasan/common.c:459
 slab_free_hook mm/slub.c:1453 [inline]
 slab_free_freelist_hook+0xd0/0x150 mm/slub.c:1486
 slab_free mm/slub.c:3051 [inline]
 kmem_cache_free+0xac/0x610 mm/slub.c:3067
 create_cache+0x1cc/0x1f0 mm/slab_common.c:429
 kmem_cache_create_usercopy+0x145/0x1d0 mm/slab_common.c:513
 p9_client_create+0x9ff/0xb90 net/9p/client.c:1061
 v9fs_session_init+0x208/0x1a00 fs/9p/v9fs.c:406
 v9fs_mount+0x7f/0x790 fs/9p/vfs_super.c:124
 legacy_get_tree+0xde/0x170 fs/fs_context.c:647
 vfs_get_tree+0x85/0x260 fs/super.c:1547
 do_new_mount fs/namespace.c:2825 [inline]
 do_mount+0x18ab/0x2660 fs/namespace.c:3145
 ksys_mount+0xc2/0xf0 fs/namespace.c:3354
 __do_sys_mount fs/namespace.c:3368 [inline]
 __se_sys_mount fs/namespace.c:3365 [inline]
 __x64_sys_mount+0xb1/0xc0 fs/namespace.c:3365
 do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e219
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f7e68b8bc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 000000000045e219
RDX: 0000000020000200 RSI: 0000000020000000 RDI: 0000000000000000
RBP: 00007f7e68b8bca0 R08: 0000000020000240 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000018
R13: 00007ffd6ca0e80f R14: 00007f7e68b8c9c0 R15: 000000000119bf8c

Allocated by task 7396:
 save_stack mm/kasan/common.c:69 [inline]
 set_track mm/kasan/common.c:77 [inline]
 __kasan_kmalloc+0x129/0x1c0 mm/kasan/common.c:510
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2803 [inline]
 slab_alloc mm/slub.c:2811 [inline]
 kmem_cache_alloc+0x1e0/0x270 mm/slub.c:2816
 kmem_cache_zalloc include/linux/slab.h:680 [inline]
 create_cache+0x3b/0x1f0 mm/slab_common.c:400
 kmem_cache_create_usercopy+0x145/0x1d0 mm/slab_common.c:513
 p9_client_create+0x9ff/0xb90 net/9p/client.c:1061
 v9fs_session_init+0x208/0x1a00 fs/9p/v9fs.c:406
 v9fs_mount+0x7f/0x790 fs/9p/vfs_super.c:124
 legacy_get_tree+0xde/0x170 fs/fs_context.c:647
 vfs_get_tree+0x85/0x260 fs/super.c:1547
 do_new_mount fs/namespace.c:2825 [inline]
 do_mount+0x18ab/0x2660 fs/namespace.c:3145
 ksys_mount+0xc2/0xf0 fs/namespace.c:3354
 __do_sys_mount fs/namespace.c:3368 [inline]
 __se_sys_mount fs/namespace.c:3365 [inline]
 __x64_sys_mount+0xb1/0xc0 fs/namespace.c:3365
 do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 7396:
 save_stack mm/kasan/common.c:69 [inline]
 set_track mm/kasan/common.c:77 [inline]
 kasan_set_free_info mm/kasan/common.c:332 [inline]
 __kasan_slab_free+0x17e/0x230 mm/kasan/common.c:471
 slab_free_hook mm/slub.c:1453 [inline]
 slab_free_freelist_hook+0xd0/0x150 mm/slub.c:1486
 slab_free mm/slub.c:3051 [inline]
 kmem_cache_free+0xac/0x610 mm/slub.c:3067
 kobject_cleanup+0x1e1/0x3c0 lib/kobject.c:708
 sysfs_slab_add+0x1a1/0x310 mm/slub.c:5825
 __kmem_cache_create+0x67c/0x6f0 mm/slub.c:4375
 create_cache+0x156/0x1f0 mm/slab_common.c:415
 kmem_cache_create_usercopy+0x145/0x1d0 mm/slab_common.c:513
 p9_client_create+0x9ff/0xb90 net/9p/client.c:1061
 v9fs_session_init+0x208/0x1a00 fs/9p/v9fs.c:406
 v9fs_mount+0x7f/0x790 fs/9p/vfs_super.c:124
 legacy_get_tree+0xde/0x170 fs/fs_context.c:647
 vfs_get_tree+0x85/0x260 fs/super.c:1547
 do_new_mount fs/namespace.c:2825 [inline]
 do_mount+0x18ab/0x2660 fs/namespace.c:3145
 ksys_mount+0xc2/0xf0 fs/namespace.c:3354
 __do_sys_mount fs/namespace.c:3368 [inline]
 __se_sys_mount fs/namespace.c:3365 [inline]
 __x64_sys_mount+0xb1/0xc0 fs/namespace.c:3365
 do_syscall_64+0xcb/0x150 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff8881f25c4500
 which belongs to the cache kmem_cache of size 472
The buggy address is located 0 bytes inside of
 472-byte region [ffff8881f25c4500, ffff8881f25c46d8)
The buggy address belongs to the page:
page:ffffea0007c97100 refcount:1 mapcount:0 mapping:ffff8881f6002000 index:0x0 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f6002000
raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881f25c4400: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
 ffff8881f25c4480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881f25c4500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8881f25c4580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881f25c4600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================