Bug#651529: rsyslog: FTBFS on hurd-i386

[Svante Signell <svante.signell@telia.com>]

Source: rsyslog
Version: 5.8.6-1
Severity: important
Tags: patch
User: debian-hurd@lists.debian.org
Usertags: hurd

rsyslog FTBFS on GNU/Hurd due to the usage of PATH_MAX in one function
static rsRetVal Load(uchar *pModName) in file realtime/modules.c. The
attached patch use dynamic allocation of strings instead of fixed length
ones. The number of changes are maybe on the order to check with
upstream if they are OK. A test program for the construct has been
created and works. The built package has also been installed kvm box and
been running there for a while and does also work.

Thanks!

diff -ur rsyslog-5.8.6/runtime/modules.c rsyslog-5.8.6.buggy/runtime/modules.c
--- rsyslog-5.8.6/runtime/modules.c	2011-10-21 11:53:02.000000000 +0200
+++ rsyslog-5.8.6.modified/runtime/modules.c	2011-12-09 14:40:08.000000000 +0100
@@ -767,7 +767,7 @@
 	DEFiRet;
 	
 	size_t iPathLen, iModNameLen;
-	uchar szPath[PATH_MAX];
+	uchar *szPath = NULL;
 	uchar *pModNameCmp;
 	int bHasExtension;
         void *pModHdlr, *pModInit;
@@ -805,11 +805,8 @@
 	do {
 		/* now build our load module name */
 		if(*pModName == '/' || *pModName == '.') {
-			*szPath = '\0';	/* we do not need to append the path - its already in the module name */
 			iPathLen = 0;
 		} else {
-			*szPath = '\0';
-
 			iPathLen = strlen((char *)pModDirCurr);
 			pModDirNext = (uchar *)strchr((char *)pModDirCurr, ':');
 			if(pModDirNext)
@@ -821,45 +818,41 @@
 					continue;
 				}
 				break;
-			} else if(iPathLen > sizeof(szPath) - 1) {
-				errmsg.LogError(0, NO_ERRCODE, "could not load module '%s', module path too long\n", pModName);
+			}
+			if((szPath = malloc(iPathLen+1)) == NULL) {
+				errmsg.LogError(0, NO_ERRCODE, "could not allocate memory '%s'\n", pModName);
 				ABORT_FINALIZE(RS_RET_MODULE_LOAD_ERR_PATHLEN);
 			}
 
-			strncat((char *) szPath, (char *)pModDirCurr, iPathLen);
-			iPathLen = strlen((char*) szPath);
+			strcpy((char *) szPath, (char *)pModDirCurr);
 
 			if(pModDirNext)
 				pModDirCurr = pModDirNext + 1;
 
 			if((szPath[iPathLen - 1] != '/')) {
-				if((iPathLen <= sizeof(szPath) - 2)) {
-					szPath[iPathLen++] = '/';
-					szPath[iPathLen] = '\0';
-				} else {
-					errmsg.LogError(0, RS_RET_MODULE_LOAD_ERR_PATHLEN, "could not load module '%s', path too long\n", pModName);
-					ABORT_FINALIZE(RS_RET_MODULE_LOAD_ERR_PATHLEN);
-				}
+				szPath[iPathLen++] = '/';
+				szPath[iPathLen] = '\0';
 			}
 		}
 
 		/* ... add actual name ... */
-		strncat((char *) szPath, (char *) pModName, sizeof(szPath) - iPathLen - 1);
+		iPathLen = iPathLen + iModNameLen + 3;
+		if((szPath = realloc(szPath, iPathLen+1)) == NULL) {
+		    errmsg.LogError(0, NO_ERRCODE, "could not allocate memory '%s'\n", pModName);
+		    ABORT_FINALIZE(RS_RET_MODULE_LOAD_ERR_PATHLEN);
+		  }
 
 		/* now see if we have an extension and, if not, append ".so" */
-		if(!bHasExtension) {
+		if(bHasExtension) {
+		  strncat((char *) szPath, (char *) pModName, iModNameLen+3);
+		} else {
 			/* we do not have an extension and so need to add ".so"
 			 * TODO: I guess this is highly importable, so we should change the
 			 * algo over time... -- rgerhards, 2008-03-05
 			 */
 			/* ... so now add the extension */
-			strncat((char *) szPath, ".so", sizeof(szPath) - strlen((char*) szPath) - 1);
-			iPathLen += 3;
-		}
-
-		if(iPathLen + strlen((char*) pModName) >= sizeof(szPath)) {
-			errmsg.LogError(0, RS_RET_MODULE_LOAD_ERR_PATHLEN, "could not load module '%s', path too long\n", pModName);
-			ABORT_FINALIZE(RS_RET_MODULE_LOAD_ERR_PATHLEN);
+			strncat((char *) szPath, (char *) pModName, iModNameLen);
+			strncat((char *) szPath, ".so", 3);
 		}
 
 		/* complete load path constructed, so ... GO! */
@@ -903,6 +896,7 @@
 	}
 
 finalize_it:
+	free(szPath);
 	pthread_mutex_unlock(&mutLoadUnload);
 	RETiRet;
 }