1 files changed, 15 insertions, 9 deletions

diff --git a/applets/applets.c b/applets/applets.c
index ebd1ff313..a974743da 100644
--- a/applets/applets.c
+++ b/applets/applets.c
@@ -320,7 +320,7 @@ static void parse_config_file(void)
 }
 
 #else
-#define parse_config_file()
+#define parse_config_file() ((void)0)
 #endif /* CONFIG_FEATURE_SUID_CONFIG */
 
 #ifdef CONFIG_FEATURE_SUID
@@ -340,20 +340,26 @@ static void check_suid(struct BB_applet *applet)
                 if (sct) {
                         mode_t m = sct->m_mode;
 
-                        if (sct->m_uid == ruid)       /* same uid */
+                        if (sct->m_uid == ruid)
+                                /* same uid */
                                 m >>= 6;
-                        else if ((sct->m_gid == rgid) || ingroup(ruid, sct->m_gid))  /* same group / in group */
+                        else if ((sct->m_gid == rgid) || ingroup(ruid, sct->m_gid))
+                                /* same group / in group */
                                 m >>= 3;
 
                         if (!(m & S_IXOTH))           /* is x bit not set ? */
                                 bb_error_msg_and_die("you have no permission to run this applet!");
 
-                        if ((sct->m_mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {     /* *both* have to be set for sgid */
-                                xsetgid(sct->m_gid);
-                        } else xsetgid(rgid);                /* no sgid -> drop */
-
-                        if (sct->m_mode & S_ISUID) xsetuid(sct->m_uid);
-                        else xsetuid(ruid);                  /* no suid -> drop */
+                        if (sct->m_gid != 0) {
+                                /* _both_ have to be set for sgid */
+                                if ((sct->m_mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
+                                        xsetgid(sct->m_gid);
+                                } else xsetgid(rgid); /* no sgid -> drop */
+                        }
+                        if (sct->m_uid != 0) {
+                                if (sct->m_mode & S_ISUID) xsetuid(sct->m_uid);
+                                else xsetuid(ruid); /* no suid -> drop */
+                        }
                 } else {
                         /* default: drop all privileges */
                         xsetgid(rgid);