diff --git a/internal/syscallcompat/sys_linux.go b/internal/syscallcompat/sys_linux.go index 08483fd..6b75957 100644 --- a/internal/syscallcompat/sys_linux.go +++ b/internal/syscallcompat/sys_linux.go @@ -58,10 +58,18 @@ func Fallocate(fd int, mode uint32, off int64, len int64) (err error) { // Openat wraps the Openat syscall. func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) { - // Why would we ever want to call this without O_NOFOLLOW and O_EXCL? - if !(flags&syscall.O_CREAT != 0 && flags&syscall.O_EXCL != 0) && flags&syscall.O_NOFOLLOW == 0 { - tlog.Warn.Printf("Openat: adding missing O_NOFOLLOW flag") - flags |= syscall.O_NOFOLLOW + if flags&syscall.O_CREAT != 0 { + // O_CREAT should be used with O_EXCL. O_NOFOLLOW has no effect with O_EXCL. + if flags&syscall.O_EXCL == 0 { + tlog.Warn.Printf("Openat: O_CREAT without O_EXCL: flags = %#x", flags) + flags |= syscall.O_EXCL + } + } else { + // If O_CREAT is not used, we should use O_NOFOLLOW + if flags&syscall.O_NOFOLLOW == 0 { + tlog.Warn.Printf("Openat: O_NOFOLLOW missing: flags = %#x", flags) + flags |= syscall.O_NOFOLLOW + } } return syscall.Openat(dirfd, path, flags, mode) }