netlink: 196 bytes leftover after parsing attributes in process `syz.5.1793'. ================================================================== BUG: KCSAN: data-race in shmem_fallocate / shmem_fault write to 0xffff888126025a18 of 8 bytes by task 11380 on cpu 1: shmem_fallocate+0x320/0x860 mm/shmem.c:3701 vfs_fallocate+0x368/0x3b0 fs/open.c:338 madvise_remove mm/madvise.c:1034 [inline] madvise_vma_behavior mm/madvise.c:1269 [inline] madvise_walk_vmas mm/madvise.c:1511 [inline] do_madvise+0x14da/0x2ad0 mm/madvise.c:1698 __do_sys_madvise mm/madvise.c:1714 [inline] __se_sys_madvise mm/madvise.c:1712 [inline] __x64_sys_madvise+0x61/0x70 mm/madvise.c:1712 x64_sys_call+0x23ab/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:29 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 0xffff888126025a18 of 8 bytes by task 11384 on cpu 0: shmem_fault+0x97/0x250 mm/shmem.c:2739 __do_fault+0xb6/0x200 mm/memory.c:4990 do_read_fault mm/memory.c:5410 [inline] do_fault mm/memory.c:5544 [inline] do_pte_missing mm/memory.c:4060 [inline] handle_pte_fault mm/memory.c:5907 [inline] __handle_mm_fault mm/memory.c:6050 [inline] handle_mm_fault+0xe98/0x2ac0 mm/memory.c:6219 faultin_page mm/gup.c:1196 [inline] __get_user_pages+0xf6a/0x2350 mm/gup.c:1491 populate_vma_page_range mm/gup.c:1929 [inline] __mm_populate+0x25b/0x3b0 mm/gup.c:2032 mm_populate include/linux/mm.h:3386 [inline] vm_mmap_pgoff+0x224/0x2d0 mm/util.c:580 ksys_mmap_pgoff+0xd0/0x330 mm/mmap.c:607 x64_sys_call+0x1940/0x2dc0 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 value changed: 0xffffc900019abca8 -> 0x0000000000000000 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 11384 Comm: syz.5.1793 Not tainted 6.14.0-rc6-syzkaller-00003-g4d872d51bc9d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 ==================================================================