Merge pull request #3028 from emersion/disambiguate-drop-root-error

Make it clear that being able to restore root is a failure

1 files changed, 18 insertions, 11 deletions

diff --git a/sway/main.c b/sway/main.c
index cc5f7187..920cea11 100644
--- a/sway/main.c
+++ b/sway/main.c
@@ -29,7 +29,7 @@
 
 static bool terminate_request = false;
 static int exit_value = 0;
-struct sway_server server;
+struct sway_server server = {0};
 
 void sway_terminate(int exit_code) {
         terminate_request = true;
@@ -194,21 +194,23 @@ static void log_kernel(void) {
 }
 
 
-static void drop_permissions(void) {
+static bool drop_permissions(void) {
         if (getuid() != geteuid() || getgid() != getegid()) {
                 if (setgid(getgid()) != 0) {
-                        wlr_log(WLR_ERROR, "Unable to drop root");
-                        exit(EXIT_FAILURE);
+                        wlr_log(WLR_ERROR, "Unable to drop root, refusing to start");
+                        return false;
                 }
                 if (setuid(getuid()) != 0) {
-                        wlr_log(WLR_ERROR, "Unable to drop root");
-                        exit(EXIT_FAILURE);
+                        wlr_log(WLR_ERROR, "Unable to drop root, refusing to start");
+                        return false;
                 }
         }
         if (setuid(0) != -1) {
-                wlr_log(WLR_ERROR, "Root privileges can be restored.");
-                exit(EXIT_FAILURE);
+                wlr_log(WLR_ERROR, "Unable to drop root (we shouldn't be able to "
+                        "restore it after setuid), refusing to start");
+                return false;
         }
+        return true;
 }
 
 void enable_debug_flag(const char *flag) {
@@ -317,11 +319,13 @@ int main(int argc, char **argv) {
         }
 
         if (optind < argc) { // Behave as IPC client
-                if(optind != 1) {
+                if (optind != 1) {
                         wlr_log(WLR_ERROR, "Don't use options with the IPC client");
                         exit(EXIT_FAILURE);
                 }
-                drop_permissions();
+                if (!drop_permissions()) {
+                        exit(EXIT_FAILURE);
+                }
                 char *socket_path = getenv("SWAYSOCK");
                 if (!socket_path) {
                         wlr_log(WLR_ERROR, "Unable to retrieve socket path");
@@ -341,7 +345,10 @@ int main(int argc, char **argv) {
         detect_proprietary(allow_unsupported_gpu);
         detect_raspi();
 
-        drop_permissions();
+        if (!drop_permissions()) {
+                server_fini(&server);
+                exit(EXIT_FAILURE);
+        }
 
         // handle SIGTERM signals
         signal(SIGTERM, sig_handler);