==================================================================
BUG: KCSAN: data-race in __rb_insert_augmented / vm_area_dup

read to 0xffff8881267bced8 of 200 bytes by task 30888 on cpu 0:
 vm_area_dup+0x70/0xf0 kernel/fork.c:359
 __split_vma+0x88/0x350 mm/mmap.c:2678
 split_vma+0x73/0xa0 mm/mmap.c:2736
 mprotect_fixup+0x43f/0x510 mm/mprotect.c:413
 do_mprotect_pkey+0x3eb/0x660 mm/mprotect.c:553
 __do_sys_mprotect mm/mprotect.c:578 [inline]
 __se_sys_mprotect mm/mprotect.c:575 [inline]
 __x64_sys_mprotect+0x51/0x70 mm/mprotect.c:575
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8881267bcf30 of 8 bytes by task 30889 on cpu 1:
 rb_set_parent_color include/linux/rbtree_augmented.h:165 [inline]
 __rb_insert lib/rbtree.c:204 [inline]
 __rb_insert_augmented+0x338/0x370 lib/rbtree.c:459
 rb_insert_augmented include/linux/rbtree_augmented.h:50 [inline]
 rb_insert_augmented_cached include/linux/rbtree_augmented.h:60 [inline]
 vma_interval_tree_insert+0x196/0x230 mm/interval_tree.c:23
 __vma_link_file+0xd9/0x110 mm/mmap.c:634
 vma_link+0xae/0x130 mm/mmap.c:660
 mmap_region+0x8bb/0xd50 mm/mmap.c:1829
 do_mmap+0x6d4/0xba0 mm/mmap.c:1577
 do_mmap_pgoff include/linux/mm.h:2348 [inline]
 vm_mmap_pgoff+0x12d/0x190 mm/util.c:496
 vm_mmap+0x9d/0xd0 mm/util.c:515
 elf_map+0xd4/0x200 fs/binfmt_elf.c:377
 load_elf_binary+0x964/0x2ec0 fs/binfmt_elf.c:983
 search_binary_handler fs/exec.c:1659 [inline]
 search_binary_handler+0x127/0x420 fs/exec.c:1636
 exec_binprm fs/exec.c:1702 [inline]
 __do_execve_file.isra.0+0xb76/0x11d0 fs/exec.c:1822
 do_execveat_common fs/exec.c:1868 [inline]
 do_execve fs/exec.c:1885 [inline]
 __do_sys_execve fs/exec.c:1961 [inline]
 __se_sys_execve fs/exec.c:1956 [inline]
 __x64_sys_execve+0x62/0x80 fs/exec.c:1956
 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: 30889 Comm: blkid Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================