================================================================== BUG: KCSAN: data-race in ext4_setattr / generic_file_buffered_read write to 0xffff8880bb0c4778 of 8 bytes by task 19044 on cpu 0: i_size_write include/linux/fs.h:896 [inline] ext4_setattr+0xd61/0xec0 fs/ext4/inode.c:5386 notify_change+0x7d4/0xa20 fs/attr.c:336 do_truncate+0xe0/0x120 fs/open.c:64 handle_truncate fs/namei.c:2901 [inline] do_open fs/namei.c:3247 [inline] path_openat+0x1a4c/0x20e0 fs/namei.c:3360 do_filp_open+0xbd/0x1d0 fs/namei.c:3387 do_sys_openat2+0x33c/0x4a0 fs/open.c:1179 do_sys_open fs/open.c:1195 [inline] ksys_open include/linux/syscalls.h:1388 [inline] __do_sys_open fs/open.c:1201 [inline] __se_sys_open fs/open.c:1199 [inline] __x64_sys_open+0xe2/0x110 fs/open.c:1199 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff8880bb0c4778 of 8 bytes by task 18997 on cpu 1: i_size_read include/linux/fs.h:874 [inline] generic_file_buffered_read+0xf71/0x1800 mm/filemap.c:2088 generic_file_read_iter+0x7d/0x3e0 mm/filemap.c:2307 ext4_file_read_iter+0x2d6/0x420 fs/ext4/file.c:74 call_read_iter include/linux/fs.h:1901 [inline] generic_file_splice_read+0x22a/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+0x562/0xb10 fs/read_write.c:1521 __do_sys_sendfile64 fs/read_write.c:1576 [inline] __se_sys_sendfile64 fs/read_write.c:1568 [inline] __x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1568 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 18997 Comm: syz-executor.1 Not tainted 5.8.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================