Do not check for existence of remote binaries

systemd-run would fail when run with -M or -H and an absolute path,
if this path did not exists locally. Allow it to continue, since we
don't have a nice way of checking if the binary exists remotely.

The case where -M or -H is used and a local path is unchanged, and we
still iterate over $PATH to find the binary. We need to convert to an
absolute path, and we don't have a nice mechanism to check remotely,
so we assume that the binary will be located in the same place locally
and remotely.

http://lists.freedesktop.org/archives/systemd-devel/2014-November/025418.html

4 files changed, 18 insertions, 13 deletions

diff --git a/src/run/run.c b/src/run/run.c
index e3b62939c7..dcefb5c376 100644
--- a/src/run/run.c
+++ b/src/run/run.c
@@ -573,9 +573,12 @@ int main(int argc, char* argv[]) {
         if (r <= 0)
                 goto finish;
 
-        r = find_binary(argv[optind], &command);
+        r = find_binary(argv[optind], arg_transport == BUS_TRANSPORT_LOCAL, &command);
         if (r < 0) {
-                log_error("Failed to find executable %s: %s", argv[optind], strerror(-r));
+                log_error("Failed to find executable %s%s: %s",
+                          argv[optind],
+                          arg_transport == BUS_TRANSPORT_LOCAL ? "" : " on local system",
+                          strerror(-r));
                 goto finish;
         }
         argv[optind] = command;
diff --git a/src/shared/path-util.c b/src/shared/path-util.c
index 67566bc76b..be03695cf8 100644
--- a/src/shared/path-util.c
+++ b/src/shared/path-util.c
@@ -563,11 +563,11 @@ int path_is_os_tree(const char *path) {
         return r >= 0;
 }
 
-int find_binary(const char *name, char **filename) {
+int find_binary(const char *name, bool local, char **filename) {
         assert(name);
 
         if (is_path(name)) {
-                if (access(name, X_OK) < 0)
+                if (local && access(name, X_OK) < 0)
                         return -errno;
 
                 if (filename) {
@@ -657,7 +657,7 @@ int fsck_exists(const char *fstype) {
 
         checker = strappenda("fsck.", fstype);
 
-        r = find_binary(checker, &p);
+        r = find_binary(checker, true, &p);
         if (r < 0)
                 return r;
 
diff --git a/src/shared/path-util.h b/src/shared/path-util.h
index 8d171a57ec..bd0d32473f 100644
--- a/src/shared/path-util.h
+++ b/src/shared/path-util.h
@@ -55,7 +55,7 @@ int path_is_mount_point(const char *path, bool allow_symlink);
 int path_is_read_only_fs(const char *path);
 int path_is_os_tree(const char *path);
 
-int find_binary(const char *name, char **filename);
+int find_binary(const char *name, bool local, char **filename);
 
 bool paths_check_timestamp(const char* const* paths, usec_t *paths_ts_usec, bool update);
 
diff --git a/src/test/test-path-util.c b/src/test/test-path-util.c
index 82090ce99f..4ebbfa9a76 100644
--- a/src/test/test-path-util.c
+++ b/src/test/test-path-util.c
@@ -85,29 +85,30 @@ static void test_path(void) {
         }
 }
 
-static void test_find_binary(const char *self) {
+static void test_find_binary(const char *self, bool local) {
         char *p;
 
-        assert_se(find_binary("/bin/sh", &p) == 0);
+        assert_se(find_binary("/bin/sh", local, &p) == 0);
         puts(p);
         assert_se(streq(p, "/bin/sh"));
         free(p);
 
-        assert_se(find_binary(self, &p) == 0);
+        assert_se(find_binary(self, local, &p) == 0);
         puts(p);
         assert_se(endswith(p, "/test-path-util"));
         assert_se(path_is_absolute(p));
         free(p);
 
-        assert_se(find_binary("sh", &p) == 0);
+        assert_se(find_binary("sh", local, &p) == 0);
         puts(p);
         assert_se(endswith(p, "/sh"));
         assert_se(path_is_absolute(p));
         free(p);
 
-        assert_se(find_binary("xxxx-xxxx", &p) == -ENOENT);
+        assert_se(find_binary("xxxx-xxxx", local, &p) == -ENOENT);
 
-        assert_se(find_binary("/some/dir/xxxx-xxxx", &p) == -ENOENT);
+        assert_se(find_binary("/some/dir/xxxx-xxxx", local, &p) ==
+                  (local ? -ENOENT : 0));
 }
 
 static void test_prefixes(void) {
@@ -263,7 +264,8 @@ static void test_path_startswith(void) {
 
 int main(int argc, char **argv) {
         test_path();
-        test_find_binary(argv[0]);
+        test_find_binary(argv[0], true);
+        test_find_binary(argv[0], false);
         test_prefixes();
         test_path_join();
         test_fsck_exists();