diff --git a/src/unistd/dup3.c b/src/unistd/dup3.c
index 1e7dc3e7..40798bde 100644
--- a/src/unistd/dup3.c
+++ b/src/unistd/dup3.c
@@ -15,7 +15,8 @@ int __dup3(int old, int new, int flags)
 		if (flags & ~O_CLOEXEC) return __syscall_ret(-EINVAL);
 	}
 	while ((r=__syscall(SYS_dup2, old, new))==-EBUSY);
-	if (flags & O_CLOEXEC) __syscall(SYS_fcntl, new, F_SETFD, FD_CLOEXEC);
+	if (r >= 0 && (flags & O_CLOEXEC))
+		__syscall(SYS_fcntl, new, F_SETFD, FD_CLOEXEC);
 #else
 	while ((r=__syscall(SYS_dup3, old, new, flags))==-EBUSY);
 #endif