autofs-5.1.7 - eliminate some more alloca usage

From: Ian Kent <raven@themaw.net>

Quite a bit of the alloca(3) usage has been eliminated over time.

Use malloc(3) for some more cases that might need to allocate a largish

amount of storage.

Signed-off-by: Ian Kent <raven@themaw.net>

---

autofs-5.1.7 - eliminate some more alloca usage

From: Ian Kent <raven@themaw.net>

Quite a bit of the alloca(3) usage has been eliminated over time.

Use malloc(3) for some more cases that might need to allocate a largish

amount of storage.

Signed-off-by: Ian Kent <raven@themaw.net>

---

 CHANGELOG                |    1 +

 modules/lookup_program.c |   11 ++++++++++-

 modules/lookup_yp.c      |   22 +++++++++++++++++++---

 modules/parse_sun.c      |   18 ++++++++++++++----

 modules/replicated.c     |   19 ++++++-------------

 5 files changed, 50 insertions(+), 21 deletions(-)

--- autofs-5.1.7.orig/CHANGELOG

+++ autofs-5.1.7/CHANGELOG

@@ -78,6 +78,7 @@

 - add missing description of null map option.

 - fix nonstrict offset mount fail handling.

 - fix concat_options() error handling.

+- eliminate some more alloca usage.

 25/01/2021 autofs-5.1.7

 - make bind mounts propagation slave by default.

--- autofs-5.1.7.orig/modules/lookup_program.c

+++ autofs-5.1.7/modules/lookup_program.c

@@ -636,7 +636,14 @@ int lookup_mount(struct autofs_point *ap

 			char *ent = NULL;

 			if (me->mapent) {

-				ent = alloca(strlen(me->mapent) + 1);

+				ent = malloc(strlen(me->mapent) + 1);

+				if (!ent) {

+					char buf[MAX_ERR_BUF];

+					char *estr = strerror_r(errno, buf, MAX_ERR_BUF);

+					error(ap->logopt, MODPREFIX "malloc: %s", estr);

+					cache_unlock(mc);

+					goto out_free;

+				}

 				strcpy(ent, me->mapent);

 			}

 			cache_unlock(mc);

@@ -644,6 +651,8 @@ int lookup_mount(struct autofs_point *ap

 			ap->entry->current = source;

 			ret = ctxt->parse->parse_mount(ap, name,

 				 name_len, ent, ctxt->parse->context);

+			if (ent)

+				free(ent);

 			goto out_free;

 		} else {

 			if (IS_MM(me) && !IS_MM_ROOT(me)) {

--- autofs-5.1.7.orig/modules/lookup_yp.c

+++ autofs-5.1.7/modules/lookup_yp.c

@@ -254,7 +254,7 @@ int yp_all_master_callback(int status, c

 	len = ypkeylen + 1 + vallen + 2;

-	buffer = alloca(len);

+	buffer = malloc(len);

 	if (!buffer) {

 		error(logopt, MODPREFIX "could not malloc parse buffer");

 		return 0;

@@ -267,6 +267,8 @@ int yp_all_master_callback(int status, c

 	master_parse_entry(buffer, timeout, logging, age);

+	free(buffer);

+

 	return 0;

 }

@@ -368,7 +370,12 @@ int yp_all_callback(int status, char *yp

 		return 0;

 	}

-	mapent = alloca(vallen + 1);

+	mapent = malloc(vallen + 1);

+	if (!mapent) {

+		error(logopt, MODPREFIX "could not malloc mapent buffer");

+		free(key);

+		return 0;

+	}

 	strncpy(mapent, val, vallen);

 	*(mapent + vallen) = '\0';

@@ -377,6 +384,7 @@ int yp_all_callback(int status, char *yp

 	cache_unlock(mc);

 	free(key);

+	free(mapent);

 	if (ret == CHE_FAIL)

 		return -1;

@@ -904,7 +912,14 @@ int lookup_mount(struct autofs_point *ap

 		}

 		if (me && (me->source == source || *me->key == '/')) {

 			mapent_len = strlen(me->mapent);

-			mapent = alloca(mapent_len + 1);

+			mapent = malloc(mapent_len + 1);

+			if (!mapent) {

+				char *estr = strerror_r(errno, buf, MAX_ERR_BUF);

+				error(ap->logopt, MODPREFIX "malloc: %s", estr);

+				cache_unlock(mc);

+				free(lkp_key);

+				return NSS_STATUS_TRYAGAIN;

+			}

 			strcpy(mapent, me->mapent);

 		}

 	}

@@ -929,6 +944,7 @@ int lookup_mount(struct autofs_point *ap

 	ret = ctxt->parse->parse_mount(ap, key, key_len,

 				       mapent, ctxt->parse->context);

+	free(mapent);

 	if (ret) {

 		/* Don't update negative cache when re-connecting */

 		if (ap->flags & MOUNT_FLAG_REMOUNT)

--- autofs-5.1.7.orig/modules/parse_sun.c

+++ autofs-5.1.7/modules/parse_sun.c

@@ -668,9 +668,16 @@ static int sun_mount(struct autofs_point

 		}

 	}

+	what = malloc(loclen + 1);

+	if (!what) {

+		char buf[MAX_ERR_BUF];

+		char *estr = strerror_r(errno, buf, MAX_ERR_BUF);

+		error(ap->logopt, MODPREFIX "malloc: %s", estr);

+		return 1;

+	}

+

 	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cur_state);

 	if (!strcmp(fstype, "nfs") || !strcmp(fstype, "nfs4")) {

-		what = alloca(loclen + 1);

 		memcpy(what, loc, loclen);

 		what[loclen] = '\0';

@@ -706,10 +713,10 @@ static int sun_mount(struct autofs_point

 		rv = mount_nfs->mount_mount(ap, root, name, namelen,

 					    what, fstype, options, mount_nfs->context);

 	} else {

-		if (!loclen)

+		if (!loclen) {

+			free(what);

 			what = NULL;

-		else {

-			what = alloca(loclen + 1);

+		} else {

 			if (*loc == ':') {

 				loclen--;

 				memcpy(what, loc + 1, loclen);

@@ -728,6 +735,9 @@ static int sun_mount(struct autofs_point

 		/* Generic mount routine */

 		rv = do_mount(ap, root, name, namelen, what, fstype, options);

 	}

+	if (what)

+		free(what);

+

 	pthread_setcancelstate(cur_state, NULL);

 	if (nonstrict && rv)

--- autofs-5.1.7.orig/modules/replicated.c

+++ autofs-5.1.7/modules/replicated.c

@@ -1041,25 +1041,18 @@ done:

 	return ret;

 }

-static int add_path(struct host *hosts, const char *path, int len)

+static int add_path(struct host *hosts, const char *path)

 {

 	struct host *this;

-	char *tmp, *tmp2;

-

-	tmp = alloca(len + 1);

-	if (!tmp)

-		return 0;

-

-	strncpy(tmp, path, len);

-	tmp[len] = '\0';

+	char *tmp;

 	this = hosts;

 	while (this) {

 		if (!this->path) {

-			tmp2 = strdup(tmp);

-			if (!tmp2)

+			tmp = strdup(path);

+			if (!tmp)

 				return 0;

-			this->path = tmp2;

+			this->path = tmp;

 		}

 		this = this->next;

 	}

@@ -1188,7 +1181,7 @@ int parse_location(unsigned logopt, stru

 						}

 					}

-					if (!add_path(*hosts, path, strlen(path))) {

+					if (!add_path(*hosts, path)) {

 						free_host_list(hosts);

 						free(str);

 						return 0;