termux-packages/root-packages/runc/libcontainer-nsenter-cloned_binary.c.patch

diff -uNr runc-1.0.0-rc8/libcontainer/nsenter/cloned_binary.c runc-1.0.0-rc8.mod/libcontainer/nsenter/cloned_binary.c
--- runc-1.0.0-rc8/libcontainer/nsenter/cloned_binary.c	2019-04-25 00:48:25.000000000 +0300
+++ runc-1.0.0-rc8.mod/libcontainer/nsenter/cloned_binary.c	2019-07-13 22:18:07.323813978 +0300
@@ -489,6 +489,30 @@
 /* Get cheap access to the environment. */
 extern char **environ;
 
+// __procfdname implementation from musl libc.
+static void musl_procfdname(char *buf, unsigned fd)
+{
+	unsigned i, j;
+	for (i=0; (buf[i] = "/proc/self/fd/"[i]); i++);
+	if (!fd) {
+		buf[i] = '0';
+		buf[i+1] = 0;
+		return;
+	}
+	for (j=fd; j; j/=10, i++);
+	buf[i] = 0;
+	for (; fd; fd/=10) buf[--i] = '0' + fd%10;
+}
+
+// fexecve implementation based on one from musl libc.
+static int musl_fexecve(int fd, char *const argv[], char *const envp[]) {
+	char buf[15 + 3*sizeof(int)];
+	musl_procfdname(buf, fd);
+	execve(buf, argv, envp);
+	if (errno == ENOENT) errno = EBADF;
+	return -1;
+}
+
 int ensure_cloned_binary(void)
 {
 	int execfd;
@@ -509,7 +533,7 @@
 	if (putenv(CLONED_BINARY_ENV "=1"))
 		goto error;
 
-	fexecve(execfd, argv, environ);
+	musl_fexecve(execfd, argv, environ);
 error:
 	close(execfd);
 	return -ENOEXEC;