================================================================== BUG: KASAN: use-after-free in constant_test_bit arch/x86/include/asm/bitops.h:328 [inline] BUG: KASAN: use-after-free in work_is_static_object+0x39/0x40 kernel/workqueue.c:442 Read of size 8 at addr ffff8801c996e3a0 by task kworker/1:2/2137 CPU: 1 PID: 2137 Comm: kworker/1:2 Not tainted 4.18.0-rc4-next-20180710+ #3 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events p9_poll_workfn Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x30d mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 constant_test_bit arch/x86/include/asm/bitops.h:328 [inline] work_is_static_object+0x39/0x40 kernel/workqueue.c:442 debug_object_activate+0x2fc/0x690 lib/debugobjects.c:508 debug_work_activate kernel/workqueue.c:491 [inline] __queue_work+0x1ca/0x1410 kernel/workqueue.c:1380 queue_work_on+0x19a/0x1e0 kernel/workqueue.c:1486 queue_work include/linux/workqueue.h:512 [inline] schedule_work include/linux/workqueue.h:570 [inline] p9_poll_mux net/9p/trans_fd.c:628 [inline] p9_poll_workfn+0x55e/0x6d0 net/9p/trans_fd.c:1107 process_one_work+0xc73/0x1ba0 kernel/workqueue.c:2153 worker_thread+0x189/0x13c0 kernel/workqueue.c:2296 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 Allocated by task 28617: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620 kmalloc include/linux/slab.h:513 [inline] kzalloc include/linux/slab.h:707 [inline] p9_fd_open net/9p/trans_fd.c:796 [inline] p9_fd_create+0x1a7/0x3f0 net/9p/trans_fd.c:1036 p9_client_create+0x915/0x16c9 net/9p/client.c:1062 v9fs_session_init+0x21a/0x1a80 fs/9p/v9fs.c:400 v9fs_mount+0x7c/0x900 fs/9p/vfs_super.c:135 legacy_get_tree+0x118/0x440 fs/fs_context.c:659 vfs_get_tree+0x1cb/0x5c0 fs/super.c:1743 do_new_mount fs/namespace.c:2567 [inline] do_mount+0x6c1/0x1fb0 fs/namespace.c:2889 ksys_mount+0x12d/0x140 fs/namespace.c:3105 __do_sys_mount fs/namespace.c:3119 [inline] __se_sys_mount fs/namespace.c:3116 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3116 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 28617: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 p9_fd_close+0x416/0x5b0 net/9p/trans_fd.c:893 p9_client_create+0xac2/0x16c9 net/9p/client.c:1076 v9fs_session_init+0x21a/0x1a80 fs/9p/v9fs.c:400 v9fs_mount+0x7c/0x900 fs/9p/vfs_super.c:135 legacy_get_tree+0x118/0x440 fs/fs_context.c:659 vfs_get_tree+0x1cb/0x5c0 fs/super.c:1743 do_new_mount fs/namespace.c:2567 [inline] do_mount+0x6c1/0x1fb0 fs/namespace.c:2889 ksys_mount+0x12d/0x140 fs/namespace.c:3105 __do_sys_mount fs/namespace.c:3119 [inline] __se_sys_mount fs/namespace.c:3116 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3116 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801c996e280 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 288 bytes inside of 512-byte region [ffff8801c996e280, ffff8801c996e480) The buggy address belongs to the page: page:ffffea0007265b80 count:1 mapcount:0 mapping:ffff8801da800940 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea000721dc08 ffffea0007232808 ffff8801da800940 raw: 0000000000000000 ffff8801c996e000 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c996e280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c996e300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801c996e380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801c996e400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c996e480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================