bug #96536: rmlabelinfo() of tape/initlabel.c corrupts memory if called more than once

In order to improve logging for tape-operations and to facilitate the current
testing surrounding this bug, the serrno code of ENOMEM has been replaced by
the more specific error ETNOLBLINFOMEM meaning "No memory available for label
information" within the setlabelinfo function.

common/serror.c

@@ -341,6 +341,7 @@ char *sys_terrlist[ETMAXERR-ETBASEOFF+2] =
    "castor::tape::net::acceptConnection interrupted",
    "Label information not found in memory",
    "Multi-drive reservations are not supported",
+   "No memory available for label information",
    "BAD ERROR NUMBER"
   };
 

h/serrno.h

@@ -345,7 +345,8 @@
 #define ETNETACCEPTINTR ETBASEOFF+34    /* castor::tape::net::acceptConnection interrupted */
 #define ETNOLBLINFO	ETBASEOFF+35    /* Label information not found in memory */
 #define ETMLTDRVRSV	ETBASEOFF+36    /* Multi-drive reservations are not supported */
-#define ETMAXERR        ETBASEOFF+36
+#define ETNOLBLINFOMEM	ETBASEOFF+37    /* No memory available for label information */
+#define ETMAXERR        ETBASEOFF+37
 
 /*
  *------------------------------------------------------------------------

tape/Ctape_mount.man

@@ -249,6 +249,9 @@ Wrong vsn.
 .TP
 .B ETNOLBLINFO
 Label information not found in memory.
+.TP
+.B ETNOLBLINFOMEM
+No memory available for label information.
 .SH SEE ALSO
 .BR vdqm_SendVolReq(3)
 .SH AUTHOR

tape/initlabel.c

@@ -91,7 +91,7 @@ int setdevinfo (const char *const path,
 	/* has a value for another path */
 	if (s_devlblinfoHasValue &&
 		strncmp(s_devlblinfo.path, path, sizeof(s_devlblinfo.path))) {
-		serrno = ENOMEM;
+		serrno = ETNOLBLINFOMEM;
 		return (-1);
 	}
 

test/unittest/tape/InitlabelTest.hpp

@@ -163,7 +163,7 @@ public:
 
   /**
    * Calling setdevinfo() a second time with a differnet path and without
-   * calling rmlabelinfo() should return -1 and set serrno to ENOMEM.
+   * calling rmlabelinfo() should return -1 and set serrno to ETNOLBLINFOMEM.
    */
   void testSetdevinfoTwiceWithDifferentPaths() {
     CPPUNIT_ASSERT_EQUAL_MESSAGE(
@@ -178,7 +178,7 @@ public:
 
     CPPUNIT_ASSERT_EQUAL_MESSAGE(
       "Checking setlabelinfo sets serrno occordingly",
-      ENOMEM,
+      ETNOLBLINFOMEM,
       serrno);
   }