================================================================== BUG: KCSAN: data-race in generic_file_buffered_read / generic_write_end write to 0xffff8880bae9a640 of 8 bytes by task 26804 on cpu 0: i_size_write include/linux/fs.h:876 [inline] generic_write_end+0x99/0x250 fs/buffer.c:2186 ext4_da_write_end+0x57e/0x760 fs/ext4/inode.c:3091 generic_perform_write+0x23b/0x390 mm/filemap.c:3516 ext4_buffered_write_iter+0x2cc/0x3b0 fs/ext4/file.c:269 ext4_file_write_iter+0x768/0x1060 include/linux/fs.h:784 call_write_iter include/linux/fs.h:1882 [inline] new_sync_write fs/read_write.c:503 [inline] vfs_write+0x665/0x6f0 fs/read_write.c:586 ksys_write+0xce/0x180 fs/read_write.c:639 __do_sys_write fs/read_write.c:651 [inline] __se_sys_write fs/read_write.c:648 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:648 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff8880bae9a640 of 8 bytes by task 26807 on cpu 1: i_size_read include/linux/fs.h:854 [inline] generic_file_buffered_read+0x1302/0x1fa0 mm/filemap.c:2266 generic_file_read_iter+0x7d/0x3e0 mm/filemap.c:2507 ext4_file_read_iter+0x2d8/0x420 fs/ext4/file.c:74 call_read_iter include/linux/fs.h:1876 [inline] generic_file_splice_read+0x22b/0x310 fs/splice.c:312 do_splice_to fs/splice.c:870 [inline] splice_direct_to_actor+0x2a8/0x660 fs/splice.c:950 do_splice_direct+0xf2/0x170 fs/splice.c:1059 do_sendfile+0x56a/0xba0 fs/read_write.c:1548 __do_sys_sendfile64 fs/read_write.c:1609 [inline] __se_sys_sendfile64 fs/read_write.c:1595 [inline] __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1595 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 26807 Comm: syz-executor.4 Not tainted 5.9.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================