syzbot

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BUG: KCSAN: data-race in mas_state_walk / mas_wmb_replace

write to 0xffff88811e41dd00 of 8 bytes by task 23115 on cpu 1:
 mte_set_node_dead lib/maple_tree.c:332 [inline]
 mas_put_in_tree lib/maple_tree.c:1563 [inline]
 mas_topiary_replace lib/maple_tree.c:2339 [inline]
 mas_wmb_replace+0x208/0xfa0 lib/maple_tree.c:2431
 mas_split lib/maple_tree.c:3050 [inline]
 mas_commit_b_node lib/maple_tree.c:3070 [inline]
 mas_wr_bnode lib/maple_tree.c:3737 [inline]
 mas_wr_store_entry+0x136b/0x26e0 lib/maple_tree.c:3769
 mas_store_prealloc+0x74d/0xa80 lib/maple_tree.c:5167
 vma_iter_store_overwrite mm/vma.h:481 [inline]
 vma_iter_store_new+0x1c5/0x200 mm/vma.h:488
 vma_complete+0x125/0x580 mm/vma.c:354
 __split_vma+0x5d9/0x650 mm/vma.c:568
 split_vma mm/vma.c:598 [inline]
 vma_modify+0x3f2/0xc80 mm/vma.c:1631
 vma_modify_flags+0x101/0x130 mm/vma.c:1649
 mprotect_fixup+0x2cc/0x570 mm/mprotect.c:816
 do_mprotect_pkey+0x6d6/0x980 mm/mprotect.c:990
 __do_sys_mprotect mm/mprotect.c:1011 [inline]
 __se_sys_mprotect mm/mprotect.c:1008 [inline]
 __x64_sys_mprotect+0x48/0x60 mm/mprotect.c:1008
 x64_sys_call+0x2752/0x3000 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 0xffff88811e41dd00 of 8 bytes by task 23118 on cpu 0:
 ma_dead_node lib/maple_tree.c:570 [inline]
 mte_dead_node lib/maple_tree.c:585 [inline]
 mas_start lib/maple_tree.c:1205 [inline]
 mas_state_walk+0x119/0x650 lib/maple_tree.c:3289
 mas_walk+0x60/0x150 lib/maple_tree.c:4597
 lock_vma_under_rcu+0x95/0x170 mm/mmap_lock.c:232
 do_user_addr_fault+0x233/0x1080 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:618

value changed: 0xffff88810b9bbf81 -> 0xffff88811e41dd00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 23118 Comm: syz.4.7128 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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