contrib/docker: add LD_PRELOAD wrapper to fopen/open/opendir syscalls

[collectd.git] / src / exec.c

diff --git a/src/exec.c b/src/exec.c
index e90f83c..fc40d4a 100644 (file)
--- a/src/exec.c
+++ b/src/exec.c
@@ -39,6 +39,10 @@
 #include <grp.h>
 #include <signal.h>
 
+#ifdef HAVE_SYS_CAPABILITY_H
+# include <sys/capability.h>
+#endif
+
 #define PL_NORMAL        0x01
 #define PL_NOTIF_ACTION  0x02
 
@@ -270,7 +274,7 @@ static void set_environment (void) /* {{{ */
       CDTIME_T_TO_DOUBLE (plugin_get_interval ()));
   setenv ("COLLECTD_INTERVAL", buffer, /* overwrite = */ 1);
 
-  ssnprintf (buffer, sizeof (buffer), "%s", hostname_g);
+  sstrncpy (buffer, hostname_g, sizeof (buffer));
   setenv ("COLLECTD_HOSTNAME", buffer, /* overwrite = */ 1);
 #else
   ssnprintf (buffer, sizeof (buffer), "COLLECTD_INTERVAL=%.3f",
@@ -543,7 +547,7 @@ failed:
 static int parse_line (char *buffer) /* {{{ */
 {
   if (strncasecmp ("PUTVAL", buffer, strlen ("PUTVAL")) == 0)
-    return (handle_putval (stdout, buffer));
+    return (cmd_handle_putval (stdout, buffer));
   else if (strncasecmp ("PUTNOTIF", buffer, strlen ("PUTNOTIF")) == 0)
     return (handle_putnotif (stdout, buffer));
   else
@@ -806,6 +810,22 @@ static int exec_init (void) /* {{{ */
 
   sigaction (SIGCHLD, &sa, NULL);
 
+#if defined(HAVE_SYS_CAPABILITY_H) && defined(CAP_SETUID) && defined(CAP_SETGID)
+  if ((check_capability (CAP_SETUID) != 0) ||
+      (check_capability (CAP_SETGID) != 0))
+  {
+    if (getuid () == 0)
+      WARNING ("exec plugin: Running collectd as root, but the CAP_SETUID "
+          "or CAP_SETGID capabilities are missing. The plugin's read function "
+          "will probably fail. Is your init system dropping capabilities?");
+    else
+      WARNING ("exec plugin: collectd doesn't have the CAP_SETUID or "
+          "CAP_SETGID capabilities. If you don't want to run collectd as root, "
+          "try running \"setcap 'cap_setuid=ep cap_setgid=ep'\" on the "
+          "collectd binary.");
+  }
+#endif
+
   return (0);
 } /* int exec_init }}} */