avoid calling non-async-signal-safe functions between fork()

and exec() (bb #889)
unit_tests: add unit-test for virusaction


git-svn: trunk@4034

ChangeLog

@@ -1,3 +1,9 @@
+Wed Jul 30 20:09:03 EEST 2008 (edwin)
+-------------------------------------
+  * clamd/others.c: avoid calling non-async-signal-safe functions between fork()
+  and exec() (bb #889)
+  * unit_tests: add unit-test for virusaction
+
 Wed Jul 30 17:02:40 CEST 2008 (tk)
 ----------------------------------
   * clamscan, clamav-milter: catch and ignore SIGXFSZ; display warning if

clamd/others.c

@@ -90,61 +90,67 @@ void virusaction(const char *filename, const char *virname, const struct cfgstru
 }
 
 #else
-
 void virusaction(const char *filename, const char *virname, const struct cfgstruct *copt)
 {
 	pid_t pid;
 	const struct cfgstruct *cpt;
+	char *buffer, *pt, *cmd, *buffer_file, *buffer_vir;
+	size_t j;
+	char *env[4];
 
-    if(!(cpt = cfgopt(copt, "VirusEvent"))->enabled)
-	return;
+	if(!(cpt = cfgopt(copt, "VirusEvent"))->enabled)
+		return;
 
-    /* NB: we need to fork here since this function modifies the environment. 
-       (Modifications to the env. are not reentrant, but we need to be.) */
-    pid = fork();
+	env[0] = getenv("PATH");
+	j = env[0] ? 1 : 0;
+	/* Allocate env vars.. to be portable env vars should not be freed */
+	buffer_file = (char *) malloc(strlen(ENV_FILE) + strlen(filename) + 2);
+	if(buffer_file) {
+		sprintf(buffer_file, "%s=%s", ENV_FILE, filename);
+		env[j++] = buffer_file;
+	}
 
-    if ( pid == 0 ) {
-	/* child... */
-	char *buffer, *pt, *cmd;
+	buffer_vir = (char *) malloc(strlen(ENV_VIRUS) + strlen(virname) + 2);
+	if(buffer_vir) {
+		sprintf(buffer_vir, "%s=%s", ENV_VIRUS, virname);
+		env[j++] = buffer_vir;
+	}
+	env[j++] = NULL;
 
 	cmd = strdup(cpt->strarg);
 
 	if(cmd && (pt = strstr(cmd, "%v"))) {
-	    buffer = (char *) malloc(strlen(cmd) + strlen(virname) + 10);
-	    if(buffer) {
-		*pt = 0; pt += 2;
-		strcpy(buffer, cmd);
-		strcat(buffer, virname);
-		strcat(buffer, pt);
-		free(cmd);
-		cmd = strdup(buffer);
-		free(buffer);
-	    }
-	}
-
-	/* Allocate env vars.. to be portable env vars should not be freed */
-	buffer = (char *) malloc(strlen(ENV_FILE) + strlen(filename) + 2);
-	if(buffer) {
-	    sprintf(buffer, "%s=%s", ENV_FILE, filename);
-	    putenv(buffer);
+		buffer = (char *) malloc(strlen(cmd) + strlen(virname) + 10);
+		if(buffer) {
+			*pt = 0; pt += 2;
+			strcpy(buffer, cmd);
+			strcat(buffer, virname);
+			strcat(buffer, pt);
+			free(cmd);
+			cmd = strdup(buffer);
+			free(buffer);
+		}
 	}
 
-	buffer = (char *) malloc(strlen(ENV_VIRUS) + strlen(virname) + 2);
-	if(buffer) {
-	    sprintf(buffer, "%s=%s", ENV_VIRUS, virname);
-	    putenv(buffer);
+	if(!cmd)
+		return;
+	/* We can only call async-signal-safe functions after fork(). */
+	pid = fork();
+
+	if ( pid == 0 ) {
+		/* child... */
+		/* WARNING: this is uninterruptable ! */
+		exit(execle("/bin/sh", "sh", "-c", cmd, NULL, env));
+	} else if (pid > 0) {
+		/* parent */
+		waitpid(pid, NULL, 0);
+	} else {
+		/* error.. */
+		logg("!VirusAction: fork failed.\n");
 	}
-	/* WARNING: this is uninterruptable ! */
-	if(cmd)
-	    exit(system(cmd));
-
-    } else if (pid > 0) {
-	/* parent */      
-	waitpid(pid, NULL, 0);
-    } else {
-	/* error.. */
-	logg("!VirusAction: fork failed.\n");
-    }
+	free(cmd);
+	free(buffer_file);
+	free(buffer_vir);
 }
 #endif /* C_WINDOWS */
 

unit_tests/check_clamd.sh

@@ -1,7 +1,7 @@
 #!/bin/sh
 die() {
 	test /tmp/clamd-test.pid && kill `cat /tmp/clamd-test.pid` 
-	rm -r test-db
+	rm -rf test-db test-clamd-viraction.conf test-clamd.log
 	exit $1
 }
 
@@ -26,4 +26,15 @@ if test "$NFILES" -ne "$NINFECTED"; then
 	grep OK clamdscan.log >&2;
 	die 4;
 fi
+cp $srcdir/test-clamd.conf test-clamd-viraction.conf
+echo "VirusEvent `pwd`/$srcdir/virusaction-test.sh `pwd` \"Virus found: %v\"" >>test-clamd-viraction.conf
+rm -f test-clamd.log
+test /tmp/clamd-test.pid && kill `cat /tmp/clamd-test.pid` 
+../clamd/.libs/lt-clamd -c test-clamd-viraction.conf || { echo "Failed to start clamd!" >&2; die 1;}
+../clamdscan/clamdscan --quiet --config-file test-clamd-viraction.conf ../test/clam.exe 
+if ! grep "Virus found: ClamAV-Test-File.UNOFFICIAL" test-clamd.log >/dev/null 2>/dev/null; then
+	echo "Virusaction test failed!" >&2;
+	cat test-clamd.log
+	die 2;
+fi
 die 0;

unit_tests/virusaction-test.sh

@@ -0,0 +1,10 @@
+#!/bin/sh
+if test ! "x$CLAM_VIRUSEVENT_FILENAME" = "x$1/../test/clam.exe"; then
+	echo "VirusEvent incorrect: $CLAM_VIRUSEVENT_FILENAME" >$1/test-clamd.log
+	exit 1
+fi
+if test ! "x$CLAM_VIRUSEVENT_VIRUSNAME" = "xClamAV-Test-File.UNOFFICIAL"; then
+	echo "VirusName incorrect: $CLAM_VIRUSEVENT_VIRUSNAME" >$1/test-clamd.log
+	exit 2
+fi
+echo $2 >$1/test-clamd.log