syzbot

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BUG: KCSAN: data-race in __filemap_remove_folio / shmem_get_folio_gfp

read-write to 0xffff88812ac66920 of 8 bytes by task 21427 on cpu 0:
 page_cache_delete mm/filemap.c:147 [inline]
 __filemap_remove_folio+0x224/0x320 mm/filemap.c:225
 __remove_mapping+0x35b/0x480 mm/vmscan.c:1467
 shrink_folio_list+0x137a/0x2550 mm/vmscan.c:2111
 reclaim_folio_list+0x7b/0x1d0 mm/vmscan.c:2790
 reclaim_pages+0x220/0x280 mm/vmscan.c:2826
 madvise_cold_or_pageout_pte_range+0x8c7/0x950 mm/madvise.c:516
 walk_pmd_range mm/pagewalk.c:128 [inline]
 walk_pud_range mm/pagewalk.c:205 [inline]
 walk_p4d_range mm/pagewalk.c:240 [inline]
 walk_pgd_range+0x7d7/0xc80 mm/pagewalk.c:277
 __walk_page_range+0xc2/0x310 mm/pagewalk.c:379
 walk_page_range+0x20b/0x330 mm/pagewalk.c:477
 madvise_pageout_page_range mm/madvise.c:574 [inline]
 madvise_pageout mm/madvise.c:601 [inline]
 madvise_vma_behavior mm/madvise.c:1019 [inline]
 madvise_walk_vmas mm/madvise.c:1248 [inline]
 do_madvise+0x1e05/0x2920 mm/madvise.c:1428
 __do_sys_madvise mm/madvise.c:1441 [inline]
 __se_sys_madvise mm/madvise.c:1439 [inline]
 __x64_sys_madvise+0x60/0x70 mm/madvise.c:1439
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88812ac66920 of 8 bytes by task 21421 on cpu 1:
 shmem_recalc_inode mm/shmem.c:360 [inline]
 shmem_get_folio_gfp+0xe1e/0x1200 mm/shmem.c:1988
 shmem_fault+0xdf/0x3c0 mm/shmem.c:2163
 __do_fault mm/memory.c:4176 [inline]
 do_read_fault mm/memory.c:4530 [inline]
 do_fault mm/memory.c:4659 [inline]
 do_pte_missing mm/memory.c:3647 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault mm/memory.c:5089 [inline]
 handle_mm_fault+0x12f4/0x2c60 mm/memory.c:5243
 do_user_addr_fault arch/x86/mm/fault.c:1440 [inline]
 handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 exc_page_fault+0x67e/0x780 arch/x86/mm/fault.c:1590
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
 rep_movs_alternative+0x30/0xb0 arch/x86/lib/copy_user_64.S:50
 copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:127 [inline]
 _copy_from_user+0x80/0xd0 lib/usercopy.c:23
 copy_from_user include/linux/uaccess.h:183 [inline]
 copy_msghdr_from_user+0x54/0x2a0 net/socket.c:2434
 recvmsg_copy_msghdr net/socket.c:2688 [inline]
 ___sys_recvmsg net/socket.c:2760 [inline]
 do_recvmmsg+0x28a/0x710 net/socket.c:2858
 __sys_recvmmsg net/socket.c:2937 [inline]
 __do_sys_recvmmsg net/socket.c:2960 [inline]
 __se_sys_recvmmsg net/socket.c:2953 [inline]
 __x64_sys_recvmmsg+0xe2/0x160 net/socket.c:2953
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000298 -> 0x0000000000000297

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 21421 Comm: syz-executor.5 Not tainted 6.4.0-rc4-syzkaller-00047-gafead42fdfca #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
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