syzbot

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BUG: KCSAN: data-race in __anon_vma_prepare / handle_mm_fault

write to 0xffff8881200b0880 of 8 bytes by task 14418 on cpu 1:
 __anon_vma_prepare+0x172/0x2f0 mm/rmap.c:213
 __vmf_anon_prepare mm/memory.c:3523 [inline]
 vmf_anon_prepare mm/internal.h:410 [inline]
 do_cow_fault mm/memory.c:5610 [inline]
 do_fault mm/memory.c:5726 [inline]
 do_pte_missing mm/memory.c:4251 [inline]
 handle_pte_fault mm/memory.c:6069 [inline]
 __handle_mm_fault mm/memory.c:6212 [inline]
 handle_mm_fault+0x1e47/0x2be0 mm/memory.c:6381
 faultin_page mm/gup.c:1186 [inline]
 __get_user_pages+0x1036/0x1fb0 mm/gup.c:1488
 populate_vma_page_range mm/gup.c:1926 [inline]
 __mm_populate+0x243/0x3a0 mm/gup.c:2029
 mm_populate include/linux/mm.h:3353 [inline]
 vm_mmap_pgoff+0x232/0x2e0 mm/util.c:584
 ksys_mmap_pgoff+0x268/0x310 mm/mmap.c:607
 x64_sys_call+0x1602/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:10
 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 0xffff8881200b0880 of 8 bytes by task 14410 on cpu 0:
 __vmf_anon_prepare mm/memory.c:3517 [inline]
 vmf_anon_prepare mm/internal.h:410 [inline]
 do_cow_fault mm/memory.c:5610 [inline]
 do_fault mm/memory.c:5726 [inline]
 do_pte_missing mm/memory.c:4251 [inline]
 handle_pte_fault mm/memory.c:6069 [inline]
 __handle_mm_fault mm/memory.c:6212 [inline]
 handle_mm_fault+0xbd0/0x2be0 mm/memory.c:6381
 faultin_page mm/gup.c:1186 [inline]
 __get_user_pages+0x1036/0x1fb0 mm/gup.c:1488
 __get_user_pages_locked mm/gup.c:1818 [inline]
 faultin_page_range+0x282/0x5b0 mm/gup.c:1978
 madvise_populate mm/madvise.c:974 [inline]
 madvise_do_behavior+0x120/0x1f20 mm/madvise.c:1731
 do_madvise+0x103/0x190 mm/madvise.c:1826
 __do_sys_madvise mm/madvise.c:1835 [inline]
 __se_sys_madvise mm/madvise.c:1833 [inline]
 __x64_sys_madvise+0x64/0x80 mm/madvise.c:1833
 x64_sys_call+0x2455/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:29
 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

value changed: 0x0000000000000000 -> 0xffff8881022761a0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 14410 Comm: syz.4.4895 Not tainted 6.16.0-rc5-syzkaller-00276-g5d5d62298b8b #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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