main: make sure the non-privileged user has proper access to the config dir

1 files changed, 21 insertions, 9 deletions

diff --git a/src/main.c b/src/main.c
index 1a04aff..15cb5a1 100644
--- a/src/main.c
+++ b/src/main.c
@@ -535,12 +535,26 @@ int main(int argc, char *argv[])
 
 #ifdef HAVE_LIBIMOBILEDEVICE
         const char* userprefdir = userpref_get_config_dir();
-
         struct stat fst;
-        int userprefdir_created = 0;
+        memset(&fst, '\0', sizeof(struct stat));
         if (stat(userprefdir, &fst) < 0) {
-                mkdir(userprefdir, 0775);
-                userprefdir_created = 1;
+                if (mkdir(userprefdir, 0775) < 0) {
+                        usbmuxd_log(LL_FATAL, "Failed to create required directory '%s': %s\n", userprefdir, strerror(errno));
+                        res = -1;
+                        goto terminate;
+                }
+                if (stat(userprefdir, &fst) < 0) {
+                        usbmuxd_log(LL_FATAL, "stat() failed after creating directory '%s': %s\n", userprefdir, strerror(errno));
+                        res = -1;
+                        goto terminate;
+                }
+        }
+
+        // make sure permission bits are set correctly
+        if (fst.st_mode != 02775) {
+                if (chmod(userprefdir, 02775) < 0) {
+                        usbmuxd_log(LL_WARNING, "chmod(%s, 02775) failed: %s", userprefdir, strerror(errno));
+                }
         }
 #endif
 
@@ -562,12 +576,10 @@ int main(int argc, char *argv[])
                         usbmuxd_log(LL_INFO, "Not dropping privileges to root");
                 } else {
 #ifdef HAVE_LIBIMOBILEDEVICE
-                        if (userprefdir_created) {
+                        /* make sure the non-privileged user has proper access to the config directory */
+                        if ((fst.st_uid != pw->pw_uid) || (fst.st_gid != pw->pw_gid)) {
                                 if (chown(userprefdir, pw->pw_uid, pw->pw_gid) < 0) {
-                                        usbmuxd_log(LL_WARNING, "chown(%s, %d, %d) failed", userprefdir, pw->pw_uid, pw->pw_gid);
-                                }
-                                if (chmod(userprefdir, 02775) < 0) {
-                                        usbmuxd_log(LL_WARNING, "chmod %s failed", userprefdir);
+                                        usbmuxd_log(LL_WARNING, "chown(%s, %d, %d) failed: %s", userprefdir, pw->pw_uid, pw->pw_gid, strerror(errno));
                                 }
                         }
 #endif