KASAN: invalid-free in p9_client

RBP: 00007fa358076ca0 R08: 0000000020000080 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000001f R13: 00007fff7dcf224f R14: 00007fa3580779c0 R15: 000000000118bf2c 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:3157 [inline] BUG: KASAN: double-free or invalid-free in kmem_cache_free+0x82/0x350 mm/slub.c:3173 CPU: 0 PID: 15981 Comm: syz-executor.5 Not tainted 5.10.0-rc3-next-20201113-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230 kasan_report_invalid_free+0x51/0x80 mm/kasan/report.c:355 ____kasan_slab_free+0x100/0x110 mm/kasan/common.c:352 kasan_slab_free include/linux/kasan.h:194 [inline] slab_free_hook mm/slub.c:1548 [inline] slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1586 slab_free mm/slub.c:3157 [inline] kmem_cache_free+0x82/0x350 mm/slub.c:3173 create_cache mm/slab_common.c:274 [inline] kmem_cache_create_usercopy+0x2ab/0x300 mm/slab_common.c:357 p9_client_create+0xc4d/0x10c0 net/9p/client.c:1063 v9fs_session_init+0x1dd/0x1770 fs/9p/v9fs.c:406 v9fs_mount+0x79/0x9b0 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1549 do_new_mount fs/namespace.c:2896 [inline] path_mount+0x12ae/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45deb9 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:00007fa358076c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000021800 RCX: 000000000045deb9 RDX: 0000000020000100 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 00007fa358076ca0 R08: 0000000020000080 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000001f R13: 00007fff7dcf224f R14: 00007fa3580779c0 R15: 000000000118bf2c Allocated by task 15981: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:39 kasan_set_track mm/kasan/common.c:47 [inline] set_alloc_info mm/kasan/common.c:403 [inline] ____kasan_kmalloc.constprop.0+0x82/0xa0 mm/kasan/common.c:434 kasan_slab_alloc include/linux/kasan.h:211 [inline] slab_post_alloc_hook mm/slab.h:512 [inline] slab_alloc_node mm/slub.c:2903 [inline] slab_alloc mm/slub.c:2911 [inline] kmem_cache_alloc+0x12a/0x470 mm/slub.c:2916 kmem_cache_zalloc include/linux/slab.h:672 [inline] create_cache mm/slab_common.c:251 [inline] kmem_cache_create_usercopy+0x1a6/0x300 mm/slab_common.c:357 p9_client_create+0xc4d/0x10c0 net/9p/client.c:1063 v9fs_session_init+0x1dd/0x1770 fs/9p/v9fs.c:406 v9fs_mount+0x79/0x9b0 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1549 do_new_mount fs/namespace.c:2896 [inline] path_mount+0x12ae/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 15981: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:39 kasan_set_track+0x1c/0x30 mm/kasan/common.c:47 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:359 ____kasan_slab_free+0xe1/0x110 mm/kasan/common.c:373 kasan_slab_free include/linux/kasan.h:194 [inline] slab_free_hook mm/slub.c:1548 [inline] slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1586 slab_free mm/slub.c:3157 [inline] kmem_cache_free+0x82/0x350 mm/slub.c:3173 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c8/0x540 lib/kobject.c:753 sysfs_slab_add+0x164/0x1d0 mm/slub.c:5656 __kmem_cache_create+0x471/0x5a0 mm/slub.c:4476 create_cache mm/slab_common.c:262 [inline] kmem_cache_create_usercopy+0x1ed/0x300 mm/slab_common.c:357 p9_client_create+0xc4d/0x10c0 net/9p/client.c:1063 v9fs_session_init+0x1dd/0x1770 fs/9p/v9fs.c:406 v9fs_mount+0x79/0x9b0 fs/9p/vfs_super.c:126 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1549 do_new_mount fs/namespace.c:2896 [inline] path_mount+0x12ae/0x1e70 fs/namespace.c:3227 do_mount fs/namespace.c:3240 [inline] __do_sys_mount fs/namespace.c:3448 [inline] __se_sys_mount fs/namespace.c:3425 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888013a45b40 which belongs to the cache kmem_cache of size 224 The buggy address is located 0 bytes inside of 224-byte region [ffff888013a45b40, ffff888013a45c20) The buggy address belongs to the page: page:00000000cfbbc7ff refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888013a45c80 pfn:0x13a45 flags: 0xfff00000000200(slab) raw: 00fff00000000200 dead000000000100 dead000000000122 ffff888010041000 raw: ffff888013a45c80 00000000800c0004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888013a45a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888013a45a80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff888013a45b00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ^ ffff888013a45b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888013a45c00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================