================================================================== BUG: KCSAN: data-race in filemap_fault / generic_write_end write to 0xffff888120905178 of 8 bytes by task 12214 on cpu 0: i_size_write include/linux/fs.h:878 [inline] generic_write_end+0x98/0x230 fs/buffer.c:2183 ext4_da_write_end+0x446/0x510 fs/ext4/inode.c:3068 generic_perform_write+0x26a/0x3f0 mm/filemap.c:3798 ext4_buffered_write_iter+0x199/0x280 fs/ext4/file.c:270 ext4_file_write_iter+0x211/0xdf0 do_iter_readv_writev+0x27b/0x300 do_iter_write+0x16f/0x5c0 fs/read_write.c:852 vfs_iter_write+0x4c/0x70 fs/read_write.c:893 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0x80/0xa0 fs/splice.c:936 splice_direct_to_actor+0x345/0x660 fs/splice.c:891 do_splice_direct+0xfb/0x180 fs/splice.c:979 do_sendfile+0x3ad/0x900 fs/read_write.c:1246 __do_sys_sendfile64 fs/read_write.c:1311 [inline] __se_sys_sendfile64 fs/read_write.c:1297 [inline] __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1297 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff888120905178 of 8 bytes by task 12215 on cpu 1: i_size_read include/linux/fs.h:856 [inline] filemap_fault+0x8a/0x740 mm/filemap.c:3114 __do_fault mm/memory.c:3915 [inline] do_shared_fault mm/memory.c:4295 [inline] do_fault+0x5df/0xb20 mm/memory.c:4373 handle_pte_fault mm/memory.c:4627 [inline] __handle_mm_fault mm/memory.c:4763 [inline] handle_mm_fault+0x825/0xa40 mm/memory.c:4861 do_user_addr_fault+0x4cd/0x940 arch/x86/mm/fault.c:1397 handle_page_fault arch/x86/mm/fault.c:1484 [inline] exc_page_fault+0x60/0x160 arch/x86/mm/fault.c:1540 asm_exc_page_fault+0x1e/0x30 copy_user_enhanced_fast_string+0xe/0x40 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline] copyout lib/iov_iter.c:155 [inline] copy_page_to_iter_iovec lib/iov_iter.c:226 [inline] __copy_page_to_iter lib/iov_iter.c:852 [inline] copy_page_to_iter+0x423/0x7b0 lib/iov_iter.c:880 copy_folio_to_iter include/linux/uio.h:153 [inline] filemap_read+0x10b2/0x1400 mm/filemap.c:2730 generic_file_read_iter+0x72/0x320 mm/filemap.c:2825 call_read_iter include/linux/fs.h:2044 [inline] new_sync_read fs/read_write.c:401 [inline] vfs_read+0x5a5/0x6a0 fs/read_write.c:482 ksys_read+0xe8/0x1a0 fs/read_write.c:620 __do_sys_read fs/read_write.c:630 [inline] __se_sys_read fs/read_write.c:628 [inline] __x64_sys_read+0x3e/0x50 fs/read_write.c:628 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x000000000004ca13 -> 0x000000000004ccb6 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 12215 Comm: syz-executor.0 Not tainted 5.18.0-rc3-syzkaller-00007-g559089e0a93d-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================