X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fprocd.git;a=blobdiff_plain;f=jail%2Fjail.c;h=9d7483c9fa4b8f37b9fbb0b65ce27aaa36173efe;hp=03ff66cb525fb3a859d4695a8d6e472b767ec204;hb=cdc3dab3cd5d0295f638de3088bc4f5c9669e7c2;hpb=4edf66c192583af866e5b8d4e8e9fcfcd68f1879

diff --git a/jail/jail.c b/jail/jail.c
index 03ff66c..9d7483c 100644
--- a/jail/jail.c
+++ b/jail/jail.c
@@ -25,6 +25,7 @@
 #include <libgen.h>
 #include <sched.h>
 #include <linux/limits.h>
+#include <signal.h>
 
 #include "capabilities.h"
 #include "elf.h"
@@ -76,7 +77,7 @@ static int mkdir_p(char *dir, mode_t mask)
 		return 0;
 
 	if (ret)
-		ERROR("mkdir failed on %s: %s\n", dir, strerror(errno));
+		ERROR("mkdir(%s, %d) failed: %s\n", dir, mask, strerror(errno));
 
 	return ret;
 }
@@ -100,7 +101,7 @@ int mount_bind(const char *root, const char *path, int readonly, int error)
 		snprintf(new, sizeof(new), "%s%s", root, path);
 		fd = creat(new, 0644);
 		if (fd == -1) {
-			ERROR("failed to create %s: %s\n", new, strerror(errno));
+			ERROR("creat(%s) failed: %s\n", new, strerror(errno));
 			return -1;
 		}
 		close(fd);
@@ -116,7 +117,7 @@ int mount_bind(const char *root, const char *path, int readonly, int error)
 		return -1;
 	}
 
-	DEBUG("mount -B %s %s\n", path, new);
+	DEBUG("mount -B %s %s (%s)\n", path, new, readonly?"ro":"rw");
 
 	return 0;
 }
@@ -125,7 +126,13 @@ static int build_jail_fs(void)
 {
 	char jail_root[] = "/tmp/ujail-XXXXXX";
 	if (mkdtemp(jail_root) == NULL) {
-		ERROR("mkdtemp(jail_root) failed: %s\n", strerror(errno));
+		ERROR("mkdtemp(%s) failed: %s\n", jail_root, strerror(errno));
+		return -1;
+	}
+
+	/* oldroot can't be MS_SHARED else pivot_root() fails */
+	if (mount("none", "/", NULL, MS_REC|MS_PRIVATE, NULL)) {
+		ERROR("private mount failed %s\n", strerror(errno));
 		return -1;
 	}
 
@@ -135,7 +142,7 @@ static int build_jail_fs(void)
 	}
 
 	if (chdir(jail_root)) {
-		ERROR("failed to chdir() in the jail root\n");
+		ERROR("chdir(%s) (jail_root) failed: %s\n", jail_root, strerror(errno));
 		return -1;
 	}
 
@@ -149,11 +156,11 @@ static int build_jail_fs(void)
 	mkdir(dirbuf, 0755);
 
 	if (pivot_root(jail_root, dirbuf) == -1) {
-		ERROR("pivot_root failed: %s\n", strerror(errno));
+		ERROR("pivot_root(%s, %s) failed: %s\n", jail_root, dirbuf, strerror(errno));
 		return -1;
 	}
 	if (chdir("/")) {
-		ERROR("chdir(/) failed: %s\n", strerror(errno));
+		ERROR("chdir(/) (after pivot_root) failed: %s\n", strerror(errno));
 		return -1;
 	}
 
@@ -238,7 +245,7 @@ static int exec_jail(void *_notused)
 		exit(EXIT_FAILURE);
 	}
 
-	if (opts.namespace && opts.hostname
+	if (opts.namespace && opts.hostname && strlen(opts.hostname) > 0
 			&& sethostname(opts.hostname, strlen(opts.hostname))) {
 		ERROR("sethostname(%s) failed: %s\n", opts.hostname, strerror(errno));
 		exit(EXIT_FAILURE);
@@ -263,8 +270,14 @@ static int exec_jail(void *_notused)
 static int jail_running = 1;
 static int jail_return_code = 0;
 
+static void jail_process_timeout_cb(struct uloop_timeout *t);
+static struct uloop_timeout jail_process_timeout = {
+	.cb = jail_process_timeout_cb,
+};
+
 static void jail_process_handler(struct uloop_process *c, int ret)
 {
+	uloop_timeout_cancel(&jail_process_timeout);
 	if (WIFEXITED(ret)) {
 		jail_return_code = WEXITSTATUS(ret);
 		INFO("jail (%d) exited with exit: %d\n", c->pid, jail_return_code);
@@ -280,12 +293,25 @@ static struct uloop_process jail_process = {
 	.cb = jail_process_handler,
 };
 
+static void jail_process_timeout_cb(struct uloop_timeout *t)
+{
+	DEBUG("jail process failed to stop, sending SIGKILL\n");
+	kill(jail_process.pid, SIGKILL);
+}
+
+static void jail_handle_signal(int signo)
+{
+	DEBUG("forwarding signal %d to the jailed process\n", signo);
+	kill(jail_process.pid, signo);
+}
+
 int main(int argc, char **argv)
 {
+	sigset_t sigmask;
 	uid_t uid = getuid();
 	char log[] = "/dev/log";
 	char ubus[] = "/var/run/ubus.sock";
-	int ch;
+	int ch, i;
 
 	if (uid) {
 		ERROR("not root, aborting: %s\n", strerror(errno));
@@ -379,10 +405,30 @@ int main(int argc, char **argv)
 		prctl(PR_SET_NAME, opts.name, NULL, NULL, NULL);
 
 	uloop_init();
+
+	sigfillset(&sigmask);
+	for (i = 0; i < _NSIG; i++) {
+		struct sigaction s = { 0 };
+
+		if (!sigismember(&sigmask, i))
+			continue;
+		if ((i == SIGCHLD) || (i == SIGPIPE))
+			continue;
+
+		s.sa_handler = jail_handle_signal;
+		sigaction(i, &s, NULL);
+	}
+
 	if (opts.namespace) {
-		jail_process.pid = clone(exec_jail,
-			child_stack + STACK_SIZE,
-			CLONE_NEWUTS | CLONE_NEWPID | CLONE_NEWNS | CLONE_NEWIPC | SIGCHLD, NULL);
+		add_mount("/dev/full", 0, -1);
+		add_mount("/dev/null", 0, -1);
+		add_mount("/dev/urandom", 0, -1);
+		add_mount("/dev/zero", 0, -1);
+
+		int flags = CLONE_NEWPID | CLONE_NEWNS | CLONE_NEWIPC | SIGCHLD;
+		if (opts.hostname)
+			flags |= CLONE_NEWUTS;
+		jail_process.pid = clone(exec_jail, child_stack + STACK_SIZE, flags, NULL);
 	} else {
 		jail_process.pid = fork();
 	}
@@ -391,12 +437,13 @@ int main(int argc, char **argv)
 		/* parent process */
 		uloop_process_add(&jail_process);
 		uloop_run();
-		uloop_done();
 		if (jail_running) {
 			DEBUG("uloop interrupted, killing jail process\n");
 			kill(jail_process.pid, SIGTERM);
-			waitpid(jail_process.pid, NULL, 0);
+			uloop_timeout_set(&jail_process_timeout, 1000);
+			uloop_run();
 		}
+		uloop_done();
 		return jail_return_code;
 	} else if (jail_process.pid == 0) {
 		/* fork child process */