KCSAN: data-race in userfaultfd_ioctl / userfaultfd

Kernel	Title	Rank 🛈	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in userfaultfd_ioctl / userfaultfd_ioctl mm fs	6	1	2378d	2378d	0/29	closed as invalid on 2019/11/19 13:44
upstream	KCSAN: data-race in userfaultfd_ioctl / userfaultfd_ioctl (3) mm fs	6	1	2249d	2249d	0/29	auto-closed as invalid on 2020/05/10 10:19
upstream	KCSAN: data-race in userfaultfd_ioctl / userfaultfd_ioctl (6) fs mm	6	1	1968d	1968d	0/29	auto-closed as invalid on 2021/01/11 23:50
upstream	KCSAN: data-race in userfaultfd_ioctl / userfaultfd_ioctl (4) mm fs	6	1	2058d	2058d	0/29	auto-closed as invalid on 2020/10/14 02:21
upstream	KCSAN: data-race in userfaultfd_ioctl / userfaultfd_ioctl (5) fs mm	6	2	2006d	2011d	0/29	auto-closed as invalid on 2020/12/04 12:11

================================================================== BUG: KCSAN: data-race in userfaultfd_ioctl / userfaultfd_ioctl write to 0xffff8881221de5f0 of 4 bytes by task 529 on cpu 0: userfaultfd_api fs/userfaultfd.c:1850 [inline] userfaultfd_ioctl+0x17c2/0x24d0 fs/userfaultfd.c:1869 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x991/0xc60 fs/ioctl.c:696 ksys_ioctl+0xbd/0xe0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:718 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff8881221de5f0 of 4 bytes by task 561 on cpu 1: userfaultfd_ioctl+0x70/0x24d0 fs/userfaultfd.c:1864 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x991/0xc60 fs/ioctl.c:696 ksys_ioctl+0xbd/0xe0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:718 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 561 Comm: syz-executor.5 Not tainted 5.4.0-rc7+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================