syzbot

==================================================================
BUG: KCSAN: data-race in mas_state_walk / mas_wmb_replace

write to 0xffff8881039a6400 of 8 bytes by task 5520 on cpu 0:
 mte_set_node_dead lib/maple_tree.c:337 [inline]
 mas_put_in_tree lib/maple_tree.c:1736 [inline]
 mas_topiary_replace lib/maple_tree.c:2553 [inline]
 mas_wmb_replace+0x20d/0x14a0 lib/maple_tree.c:2645
 mas_split lib/maple_tree.c:3384 [inline]
 mas_commit_b_node lib/maple_tree.c:3404 [inline]
 mas_wr_bnode lib/maple_tree.c:4073 [inline]
 mas_wr_store_entry+0x1773/0x2b50 lib/maple_tree.c:4105
 mas_store_prealloc+0x74d/0x9e0 lib/maple_tree.c:5506
 vma_iter_store_overwrite mm/vma.h:502 [inline]
 vma_iter_store_new+0x1c5/0x200 mm/vma.h:509
 vma_complete+0x125/0x580 mm/vma.c:351
 __split_vma+0x5d9/0x650 mm/vma.c:565
 split_vma mm/vma.c:595 [inline]
 vma_modify+0x3f2/0xc80 mm/vma.c:1626
 vma_modify_flags+0x101/0x130 mm/vma.c:1644
 mprotect_fixup+0x2cc/0x570 mm/mprotect.c:658
 do_mprotect_pkey+0x6d6/0x980 mm/mprotect.c:832
 __do_sys_mprotect mm/mprotect.c:853 [inline]
 __se_sys_mprotect mm/mprotect.c:850 [inline]
 __x64_sys_mprotect+0x48/0x60 mm/mprotect.c:850
 x64_sys_call+0x2794/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:11
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881039a6400 of 8 bytes by task 5522 on cpu 1:
 ma_dead_node lib/maple_tree.c:575 [inline]
 mte_dead_node lib/maple_tree.c:590 [inline]
 mas_start lib/maple_tree.c:1378 [inline]
 mas_state_walk+0x119/0x650 lib/maple_tree.c:3623
 mas_walk+0x30/0x120 lib/maple_tree.c:4936
 lock_vma_under_rcu+0xa2/0x2f0 mm/mmap_lock.c:143
 do_user_addr_fault+0x233/0x1090 arch/x86/mm/fault.c:1327
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

value changed: 0xffff88811947f901 -> 0xffff8881039a6400

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5522 Comm: syz.0.626 Not tainted 6.16.0-rc4-syzkaller-00049-gb4911fb0b060 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================