From: Baptiste Daroussin <bapt@FreeBSD.org>
Date: Mon, 26 Dec 2022 13:56:23 +0000 (+0100)
Subject: is_subbed: do not manipulate memory, prefer file descriptor
X-Git-Tag: RELEASE_1_4_0_a2~85
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=847b20aec120d5a24bc18c4ac4fa60ef47fe891a;p=thirdparty%2Fmlmmj.git

is_subbed: do not manipulate memory, prefer file descriptor
---

diff --git a/include/subscriberfuncs.h b/include/subscriberfuncs.h
index 57f99cca..36a1331c 100644
--- a/include/subscriberfuncs.h
+++ b/include/subscriberfuncs.h
@@ -24,8 +24,10 @@
 #ifndef SUBSCRIBERFUNC_H
 #define SUBSCRIBERFUNC_H
 
+#include <stdbool.h>
+
 off_t find_subscriber(int fd, const char *address);
-int is_subbed_in(const char *subddirname, const char *address);
-enum subtype is_subbed(const char *listdir, const char *address, int both);
+int is_subbed_in(int fd, const char *subddirname, const char *address);
+enum subtype is_subbed(const char *listdir, const char *address, bool both);
 
 #endif /* SUBSCRIBERFUNC_H */
diff --git a/src/mlmmj-unsub.c b/src/mlmmj-unsub.c
index 9571d649..e0ed4234 100644
--- a/src/mlmmj-unsub.c
+++ b/src/mlmmj-unsub.c
@@ -24,6 +24,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <sys/fcntl.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/mman.h>
@@ -292,7 +293,7 @@ int main(int argc, char **argv)
 	int nogennotsubscribed = 0;
 	int status;
 	char *listaddr, *listdelim, *listdir = NULL, *address = NULL;
-	char *mlmmjsend, *bindir, *subdir, *subddirname;
+	char *mlmmjsend, *bindir, *subdir;
 	enum subtype typesub = SUB_ALL;
 	enum subreason reasonsub = SUB_ADMIN;
 	uid_t uid;
@@ -406,23 +407,32 @@ int main(int argc, char **argv)
 	}
 
 	if (typesub == SUB_ALL) {
-		subbed = is_subbed(listdir, address, 0) != SUB_NONE;
+		subbed = is_subbed(listdir, address, false) != SUB_NONE;
 	} else {
 		switch(typesub) {
 			default:
 			case SUB_NORMAL:
-				subdir = "/subscribers.d/";
+				subdir = "subscribers.d";
 				break;
 			case SUB_DIGEST:
-				subdir = "/digesters.d/";
+				subdir = "digesters.d";
 				break;
 			case SUB_NOMAIL:
-				subdir = "/nomailsubs.d/";
+				subdir = "nomailsubs.d";
 				break;
 		}
-		subddirname = concatstr(2, listdir, subdir);
-		subbed = is_subbed_in(subddirname, address);
-		free(subddirname);
+		int listdirfd = open(listdir, O_DIRECTORY);
+		if (listdirfd == -1) {
+			log_error(LOG_ARGS, "Could not opendir(%s)", listdir);
+			exit(EXIT_FAILURE);
+		}
+		int subdirfd = openat(listdirfd, subdir, O_DIRECTORY);
+		if (subdirfd == -1) {
+			log_error(LOG_ARGS, "Could not opendir(%s/%s)", listdir, subdir);
+			exit(EXIT_FAILURE);
+		}
+		close(listdirfd);
+		subbed = is_subbed_in(subdirfd, subdir, address);
 	}
 
 	if(!subbed) {
diff --git a/src/subscriberfuncs.c b/src/subscriberfuncs.c
index c0c99890..8b2499ca 100644
--- a/src/subscriberfuncs.c
+++ b/src/subscriberfuncs.c
@@ -37,7 +37,6 @@
 #include "mygetline.h"
 #include "log_error.h"
 #include "wrappers.h"
-#include "strgen.h"
 
 char *subtype_strs[] = {
 	"normal",
@@ -109,16 +108,16 @@ off_t find_subscriber(int fd, const char *address)
 	return (off_t)-1;
 }
 
-int is_subbed_in(const char *subddirname, const char *address)
+int
+is_subbed_in(int dirfd, const char *subdirname, const char *address)
 {
 	int retval = 0, subread;
-	char *subreadname;
 	off_t suboff;
 	DIR *subddir;
 	struct dirent *dp;
 
-	if((subddir = opendir(subddirname)) == NULL) {
-		log_error(LOG_ARGS, "Could not opendir(%s)", subddirname);
+	if((subddir = fdopendir(dirfd)) == NULL) {
+		log_error(LOG_ARGS, "Could not opendir(%s)", subdirname);
 		exit(EXIT_FAILURE);
 	}
 
@@ -128,17 +127,15 @@ int is_subbed_in(const char *subddirname, const char *address)
 		if(!strcmp(dp->d_name, ".."))
 			continue;
 
-		subreadname = concatstr(2, subddirname, dp->d_name);
-		subread = open(subreadname, O_RDONLY);
+		subread = openat(dirfd, dp->d_name, O_RDONLY);
 		if(subread < 0) {
-	                log_error(LOG_ARGS, "Could not open %s", subreadname);
-			free(subreadname);
+			log_error(LOG_ARGS, "Could not open %s/%s",
+			  subdirname, dp->d_name);
 			continue;
 		}
 
 		suboff = find_subscriber(subread, address);
 		close(subread);
-		free(subreadname);
 
 		if(suboff == -1) {
 			continue;
@@ -152,32 +149,32 @@ int is_subbed_in(const char *subddirname, const char *address)
 	return retval;
 }
 
-enum subtype is_subbed(const char *listdir, const char *address, int both)
+enum subtype
+is_subbed(const char *listdir, const char *address, bool both)
 {
-	int retval;
-	char *subddirname;
 	enum subtype typesub = SUB_NONE;
-	
-	subddirname = concatstr(2, listdir, "/subscribers.d/");
-	retval = is_subbed_in(subddirname, address);
-	free(subddirname);
-	if (retval) {
+	int fd, dirfd;
+
+	dirfd = open(listdir, O_DIRECTORY);
+	if (dirfd == -1) {
+		log_error(LOG_ARGS, "Could not opendir()");
+		exit(EXIT_FAILURE);
+	}
+	fd = openat(dirfd, "subscribers.d", O_DIRECTORY);
+	if (fd != -1 && is_subbed_in(fd, "subscribers.d", address)) {
 		if (!both) return SUB_NORMAL;
 		typesub = SUB_NORMAL;
 	}
 
-	subddirname = concatstr(2, listdir, "/digesters.d/");
-	retval = is_subbed_in(subddirname, address);
-	free(subddirname);
-	if (retval) {
+	fd = openat(dirfd, "digesters.d", O_DIRECTORY);
+	if (fd != -1 && is_subbed_in(fd, "digesters.d", address)) {
 		if (typesub == SUB_NORMAL) return SUB_BOTH;
 		return SUB_DIGEST;
 	}
 
-	subddirname = concatstr(2, listdir, "/nomailsubs.d/");
-	retval = is_subbed_in(subddirname, address);
-	free(subddirname);
-	if (retval) return SUB_NOMAIL;
+	fd = openat(dirfd, "nomailsubs.d", O_DIRECTORY);
+	if (fd != -1 && is_subbed_in(fd, "nomailsubs.d", address))
+		return SUB_NOMAIL;
 
 	return typesub;
 }