================================================================== BUG: KCSAN: data-race in ext4_handle_inode_extension / filemap_read write to 0xffff888009659c90 of 8 bytes by task 16435 on cpu 0: i_size_write include/linux/fs.h:872 [inline] ext4_update_inode_size fs/ext4/ext4.h:3292 [inline] ext4_handle_inode_extension+0x226/0x550 fs/ext4/file.c:331 ext4_dio_write_iter fs/ext4/file.c:557 [inline] ext4_file_write_iter+0xef4/0x10b0 fs/ext4/file.c:661 call_write_iter include/linux/fs.h:1977 [inline] do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740 do_iter_write+0x112/0x4c0 fs/read_write.c:866 vfs_iter_write+0x4c/0x70 fs/read_write.c:907 iter_file_splice_write+0x40a/0x750 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+0x345/0x650 fs/splice.c:891 do_splice_direct+0xf5/0x170 fs/splice.c:979 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260 __do_sys_sendfile64 fs/read_write.c:1325 [inline] __se_sys_sendfile64 fs/read_write.c:1311 [inline] __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff888009659c90 of 8 bytes by task 16449 on cpu 1: i_size_read include/linux/fs.h:850 [inline] filemap_read+0x1dc/0x7b0 mm/filemap.c:2470 generic_file_read_iter+0x82/0x410 mm/filemap.c:2609 ext4_file_read_iter+0x2e0/0x420 fs/ext4/file.c:74 call_read_iter include/linux/fs.h:1971 [inline] generic_file_splice_read+0x22a/0x310 fs/splice.c:311 do_splice_to fs/splice.c:796 [inline] splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870 do_splice_direct+0xf5/0x170 fs/splice.c:979 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260 __do_sys_sendfile64 fs/read_write.c:1319 [inline] __se_sys_sendfile64 fs/read_write.c:1311 [inline] __x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1311 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 16449 Comm: syz-executor.4 Not tainted 5.12.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================