Merge pull request #908 from richardmaw-codethink/nspawn-path-escapes-v3

Allow arbitrary file paths to be passed to nspawn (v3)

1 files changed, 65 insertions, 25 deletions

diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index 0e74f20f1a..347260013a 100644
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -655,17 +655,22 @@ static int parse_argv(int argc, char *argv[]) {
 
                 case ARG_BIND:
                 case ARG_BIND_RO: {
+                        const char *current = optarg;
                         _cleanup_free_ char *source = NULL, *destination = NULL;
                         CustomMount *m;
-                        char *e;
+                        _cleanup_strv_free_ char **strv = NULL;
 
-                        e = strchr(optarg, ':');
-                        if (e) {
-                                source = strndup(optarg, e - optarg);
-                                destination = strdup(e + 1);
-                        } else {
-                                source = strdup(optarg);
-                                destination = strdup(optarg);
+                        r = extract_many_words(&current, ":", EXTRACT_DONT_COALESCE_SEPARATORS, &source, &destination, NULL);
+                        switch (r) {
+                        case 1:
+                                destination = strdup(source);
+                        case 2:
+                                break;
+                        case -ENOMEM:
+                                return log_oom();
+                        default:
+                                log_error("Invalid bind mount specification: %s", optarg);
+                                return -EINVAL;
                         }
 
                         if (!source || !destination)
@@ -690,18 +695,21 @@ static int parse_argv(int argc, char *argv[]) {
                 }
 
                 case ARG_TMPFS: {
+                        const char *current = optarg;
                         _cleanup_free_ char *path = NULL, *opts = NULL;
                         CustomMount *m;
-                        char *e;
 
-                        e = strchr(optarg, ':');
-                        if (e) {
-                                path = strndup(optarg, e - optarg);
-                                opts = strdup(e + 1);
-                        } else {
-                                path = strdup(optarg);
-                                opts = strdup("mode=0755");
+                        r = extract_first_word(&current, &path, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+                        if (r == -ENOMEM)
+                                return log_oom();
+                        else if (r < 0) {
+                                log_error("Invalid tmpfs specification: %s", optarg);
+                                return r;
                         }
+                        if (r)
+                                opts = strdup(current);
+                        else
+                                opts = strdup("mode=0755");
 
                         if (!path || !opts)
                                 return log_oom();
@@ -731,9 +739,13 @@ static int parse_argv(int argc, char *argv[]) {
                         unsigned n = 0;
                         char **i;
 
-                        lower = strv_split(optarg, ":");
-                        if (!lower)
+                        r = strv_split_extract(&lower, optarg, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+                        if (r == -ENOMEM)
                                 return log_oom();
+                        else if (r < 0) {
+                                log_error("Invalid overlay specification: %s", optarg);
+                                return r;
+                        }
 
                         STRV_FOREACH(i, lower) {
                                 if (!path_is_absolute(*i)) {
@@ -1227,6 +1239,21 @@ static int mount_tmpfs(const char *dest, CustomMount *m) {
         return 0;
 }
 
+static char *joined_and_escaped_lower_dirs(char * const *lower) {
+        _cleanup_strv_free_ char **sv = NULL;
+
+        sv = strv_copy(lower);
+        if (!sv)
+                return NULL;
+
+        strv_reverse(sv);
+
+        if (!strv_shell_escape(sv, ",:"))
+                return NULL;
+
+        return strv_join(sv, ":");
+}
+
 static int mount_overlay(const char *dest, CustomMount *m) {
         _cleanup_free_ char *lower = NULL;
         const char *where, *options;
@@ -1243,19 +1270,32 @@ static int mount_overlay(const char *dest, CustomMount *m) {
 
         (void) mkdir_p_label(m->source, 0755);
 
-        strv_reverse(m->lower);
-        lower = strv_join(m->lower, ":");
-        strv_reverse(m->lower);
+        lower = joined_and_escaped_lower_dirs(m->lower);
         if (!lower)
                 return log_oom();
 
-        if (m->read_only)
-                options = strjoina("lowerdir=", m->source, ":", lower);
-        else {
+        if (m->read_only) {
+                _cleanup_free_ char *escaped_source = NULL;
+
+                escaped_source = shell_escape(m->source, ",:");
+                if (!escaped_source)
+                        return log_oom();
+
+                options = strjoina("lowerdir=", escaped_source, ":", lower);
+        } else {
+                _cleanup_free_ char *escaped_source = NULL, *escaped_work_dir = NULL;
+
                 assert(m->work_dir);
                 (void) mkdir_label(m->work_dir, 0700);
 
-                options = strjoina("lowerdir=", lower, ",upperdir=", m->source, ",workdir=", m->work_dir);
+                escaped_source = shell_escape(m->source, ",:");
+                if (!escaped_source)
+                        return log_oom();
+                escaped_work_dir = shell_escape(m->work_dir, ",:");
+                if (!escaped_work_dir)
+                        return log_oom();
+
+                options = strjoina("lowerdir=", lower, ",upperdir=", escaped_source, ",workdir=", escaped_work_dir);
         }
 
         if (mount("overlay", where, "overlay", m->read_only ? MS_RDONLY : 0, options) < 0)