[syzbot] [mm?] KCSAN: data-race in mas_wr_store_entry / mtree_range_walk

[syzbot <syzbot+e01fa33e67abb0b3b3bb@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    88264981f208 Merge tag 'sched_ext-for-6.12' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1237ec27980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e6702f5f2b8ed242
dashboard link: https://syzkaller.appspot.com/bug?extid=e01fa33e67abb0b3b3bb
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/95bba355b2ed/disk-88264981.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/75966f4e5286/vmlinux-88264981.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7f1578876250/bzImage-88264981.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e01fa33e67abb0b3b3bb@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in mas_wr_store_entry / mtree_range_walk

write to 0xffff888114555710 of 8 bytes by task 9573 on cpu 1:
 mas_wr_slot_store lib/maple_tree.c:3889 [inline]
 mas_wr_store_entry+0x146b/0x2d00 lib/maple_tree.c:4075
 mas_store_prealloc+0x6bf/0x960 lib/maple_tree.c:5520
 vma_iter_store mm/vma.h:470 [inline]
 commit_merge+0x441/0x740 mm/vma.c:609
 vma_expand+0x211/0x360 mm/vma.c:1024
 vma_merge_new_range+0x2cf/0x3e0 mm/vma.c:963
 mmap_region+0x887/0x16e0 mm/mmap.c:1416
 do_mmap+0x718/0xb60 mm/mmap.c:496
 vm_mmap_pgoff+0x133/0x290 mm/util.c:588
 ksys_mmap_pgoff+0xd0/0x330 mm/mmap.c:542
 x64_sys_call+0x1884/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:10
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888114555710 of 8 bytes by task 9574 on cpu 0:
 mtree_range_walk+0x1b4/0x460 lib/maple_tree.c:2779
 mas_state_walk lib/maple_tree.c:3601 [inline]
 mas_walk+0x16e/0x320 lib/maple_tree.c:4948
 lock_vma_under_rcu+0x95/0x260 mm/memory.c:6224
 do_user_addr_fault arch/x86/mm/fault.c:1329 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x150/0x650 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

value changed: 0x00007f8311576fff -> 0xffffffff8529a680

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 9574 Comm: syz.0.2084 Tainted: G        W          6.11.0-syzkaller-08481-g88264981f208 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup