==================================================================
BUG: KCSAN: data-race in __anon_vma_prepare / do_anonymous_page

write to 0xffff8881081b6e08 of 8 bytes by task 22832 on cpu 0:
 __anon_vma_prepare+0x12c/0x2a0 mm/rmap.c:210
 anon_vma_prepare include/linux/rmap.h:150 [inline]
 do_anonymous_page+0x7c1/0xa10 mm/memory.c:3824
 handle_pte_fault mm/memory.c:4625 [inline]
 __handle_mm_fault mm/memory.c:4763 [inline]
 handle_mm_fault+0x83c/0xa40 mm/memory.c:4861
 do_user_addr_fault+0x4cd/0x940 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1484 [inline]
 exc_page_fault+0x60/0x160 arch/x86/mm/fault.c:1540
 asm_exc_page_fault+0x1e/0x30

read to 0xffff8881081b6e08 of 8 bytes by task 22833 on cpu 1:
 anon_vma_prepare include/linux/rmap.h:147 [inline]
 do_anonymous_page+0x127/0xa10 mm/memory.c:3824
 handle_pte_fault mm/memory.c:4625 [inline]
 __handle_mm_fault mm/memory.c:4763 [inline]
 handle_mm_fault+0x83c/0xa40 mm/memory.c:4861
 do_user_addr_fault+0x4cd/0x940 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1484 [inline]
 exc_page_fault+0x60/0x160 arch/x86/mm/fault.c:1540
 asm_exc_page_fault+0x1e/0x30
 __put_user_nocheck_4+0x3/0x11
 rawv6_ioctl+0xc3/0xd0 net/ipv6/raw.c:1168
 inet6_ioctl+0x9f/0x170 net/ipv6/af_inet6.c:583
 sock_do_ioctl+0x7d/0x250 net/socket.c:1122
 sock_ioctl+0x343/0x570 net/socket.c:1239
 vfs_ioctl fs/ioctl.c:51 [inline]
 do_vfs_ioctl+0x781/0x1390 fs/ioctl.c:830
 __do_sys_ioctl fs/ioctl.c:868 [inline]
 __se_sys_ioctl+0x83/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000000 -> 0xffff88811d9979b0

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 22833 Comm: syz-executor.3 Not tainted 5.18.0-rc3-syzkaller-00218-g13bc32bad705-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================