Replace the use of the global variable 'modpath' in diagnostic

messages within verify_it with the use of a 'module_name'
parameter passed in.

Add a comment in insert_module explaining why it's ok to
overwrite the 'path' parameter with the canonicalized path.

3 files changed, 14 insertions, 10 deletions

diff --git a/runtime/staprun/modverify.c b/runtime/staprun/modverify.c
index 059856ee..514f09f0 100644
--- a/runtime/staprun/modverify.c
+++ b/runtime/staprun/modverify.c
@@ -202,7 +202,7 @@ check_cert_db_permissions (const char *cert_db_path) {
 
 static int
 verify_it (const char *signatureName, const SECItem *signature,
-	   const void *module_data, off_t module_size,
+	   const char *module_name, const void *module_data, off_t module_size,
 	   const SECKEYPublicKey *pubKey)
 {
   VFYContext *vfy;
@@ -224,7 +224,7 @@ verify_it (const char *signatureName, const SECItem *signature,
   if (secStatus != SECSuccess)
     {
       fprintf (stderr, "Unable to initialize verification context while verifying %s using the signature in %s.\n",
-	       modpath, signatureName);
+	       module_name, signatureName);
       nssError ();
       return MODULE_CHECK_ERROR;
     }
@@ -234,7 +234,7 @@ verify_it (const char *signatureName, const SECItem *signature,
   if (secStatus != SECSuccess)
     {
       fprintf (stderr, "Error while verifying %s using the signature in %s.\n",
-	       modpath, signatureName);
+	       module_name, signatureName);
       nssError ();
       return MODULE_CHECK_ERROR;
     }
@@ -243,7 +243,7 @@ verify_it (const char *signatureName, const SECItem *signature,
   secStatus = VFY_End (vfy);
   if (secStatus != SECSuccess) {
     fprintf (stderr, "Unable to verify the signed module %s. It may have been altered since it was created.\n",
-	     modpath);
+	     module_name);
     nssError ();
     return MODULE_ALTERED;
   }
@@ -251,8 +251,8 @@ verify_it (const char *signatureName, const SECItem *signature,
   return MODULE_OK;
 }
 
-int verify_module (const char *signatureName, const void *module_data,
-		   off_t module_size)
+int verify_module (const char *signatureName, const char* module_name,
+		   const void *module_data, off_t module_size)
 {
   const char *dbdir  = SYSCONFDIR "/systemtap/staprun";
   SECKEYPublicKey *pubKey;
@@ -356,7 +356,8 @@ int verify_module (const char *signatureName, const void *module_data,
 	}
 
       /* Verify the file. */
-      rc = verify_it (signatureName, & signature, module_data, module_size, pubKey);
+      rc = verify_it (signatureName, & signature,
+		      module_name, module_data, module_size, pubKey);
       if (rc == MODULE_OK || rc == MODULE_ALTERED || rc == MODULE_CHECK_ERROR)
 	break; /* resolved or error */
     }
diff --git a/runtime/staprun/modverify.h b/runtime/staprun/modverify.h
index 730a5e86..c35adc29 100644
--- a/runtime/staprun/modverify.h
+++ b/runtime/staprun/modverify.h
@@ -1,4 +1,5 @@
-int verify_module (const char *signature_name, const void *module_data, off_t module_size);
+int verify_module (const char *signature_name, const char *module_name,
+		   const void *module_data, off_t module_size);
 
 /* return codes for verify_module.  */
 #define MODULE_OK           1
diff --git a/runtime/staprun/staprun_funcs.c b/runtime/staprun/staprun_funcs.c
index 47ad6a19..89f78ade 100644
--- a/runtime/staprun/staprun_funcs.c
+++ b/runtime/staprun/staprun_funcs.c
@@ -84,7 +84,9 @@ int insert_module(
 
         /* Overwrite the path with the canonicalized one, to defeat
            a possible race between path and signature checking below and,
-	   somewhat later, module loading. */
+	   somewhat later, module loading. This path gets propogated to the
+	   helper functions called by this function and is not used for any
+	   other purpose, so it is ok to overwrite the 'path' parameter.  */
         path = strdup (module_realpath);
         if (path == NULL) {
 		_perr("allocating memory failed");
@@ -256,7 +258,7 @@ check_signature(const char *path, const void *module_data, off_t module_size)
   }
   sprintf (signature_realpath, "%s.sgn", path);
 
-  rc = verify_module (signature_realpath, module_data, module_size);
+  rc = verify_module (signature_realpath, path, module_data, module_size);
 
   dbug(2, "verify_module returns %d\n", rc);