diff --git a/bin/xbps-bin/check.c b/bin/xbps-bin/check.c
index f63d457a..95d12070 100644
--- a/bin/xbps-bin/check.c
+++ b/bin/xbps-bin/check.c
@@ -64,8 +64,16 @@ xbps_check_pkg_integrity_all(void)
 		return ENOENT;
 
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);
-		prop_dictionary_get_cstring_nocopy(obj, "version", &version);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgname", &pkgname)) {
+			prop_object_iterator_release(iter);
+			return errno;
+		}
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "version", &version)) {
+			prop_object_iterator_release(iter);
+			return errno;
+		}
 		printf("Checking %s-%s ...\n", pkgname, version);
 		if ((rv = xbps_check_pkg_integrity(pkgname)) != 0)
 			nbrokenpkgs++;
@@ -177,7 +185,12 @@ xbps_check_pkg_integrity(const char *pkgname)
 			goto out2;
 		}
 		while ((obj = prop_object_iterator_next(iter))) {
-			prop_dictionary_get_cstring_nocopy(obj, "file", &file);
+			if (!prop_dictionary_get_cstring_nocopy(obj,
+			    "file", &file)) {
+				prop_object_iterator_release(iter);
+				rv = errno;
+				goto out2;
+			}
 			path = xbps_xasprintf("%s/%s",
 			    xbps_get_rootdir(), file);
 			if (path == NULL) {
@@ -185,8 +198,13 @@ xbps_check_pkg_integrity(const char *pkgname)
 				rv = errno;
 				goto out2;
 			}
-                        prop_dictionary_get_cstring_nocopy(obj,
-                            "sha256", &sha256);
+                        if (!prop_dictionary_get_cstring_nocopy(obj,
+                            "sha256", &sha256)) {
+				free(path);
+				prop_object_iterator_release(iter);
+				rv = errno;
+				goto out2;
+			}
 			rv = xbps_check_file_hash(path, sha256);
 			switch (rv) {
 			case 0:
@@ -227,7 +245,12 @@ xbps_check_pkg_integrity(const char *pkgname)
 			goto out2;
 		}
 		while ((obj = prop_object_iterator_next(iter))) {
-			prop_dictionary_get_cstring_nocopy(obj, "file", &file);
+			if (!prop_dictionary_get_cstring_nocopy(obj,
+			    "file", &file)) {
+				prop_object_iterator_release(iter);
+				rv = errno;
+				goto out2;
+			}
 			path = xbps_xasprintf("%s/%s",
 			    xbps_get_rootdir(), file);
 			if (path == NULL) {
@@ -264,6 +287,11 @@ xbps_check_pkg_integrity(const char *pkgname)
 		}
 		while ((obj = prop_object_iterator_next(iter))) {
 			reqpkg = prop_string_cstring_nocopy(obj);
+			if (reqpkg == NULL) {
+				prop_object_iterator_release(iter);
+				rv = EINVAL;
+				goto out2;
+			}
 			if (xbps_check_is_installed_pkg(reqpkg) <= 0) {
 				rv = ENOENT;
 				printf("%s: dependency not satisfied: %s\n",
diff --git a/bin/xbps-bin/install.c b/bin/xbps-bin/install.c
index 76b48058..508f4685 100644
--- a/bin/xbps-bin/install.c
+++ b/bin/xbps-bin/install.c
@@ -82,7 +82,10 @@ check_pkg_hashes(prop_object_iterator_t iter)
 
 	printf("Checking binary package file(s) integrity...\n");
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgname", &pkgname))
+			return errno;
+
 		state = 0;
 		if (xbps_get_pkg_state_dictionary(obj, &state) != 0)
 			return EINVAL;
@@ -90,8 +93,12 @@ check_pkg_hashes(prop_object_iterator_t iter)
 		if (state == XBPS_PKG_STATE_UNPACKED)
 			continue;
 
-		prop_dictionary_get_cstring_nocopy(obj, "repository", &repoloc);
-		prop_dictionary_get_cstring_nocopy(obj, "filename", &filename);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "repository", &repoloc))
+			return errno;
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "filename", &filename))
+			return errno;
 		rv = xbps_check_pkg_file_hash(obj, repoloc);
 		if (rv != 0 && rv != ERANGE) {
 			printf("Unexpected error while checking hash for "
@@ -118,16 +125,24 @@ download_package_list(prop_object_iterator_t iter)
 
 	printf("Downloading binary package file(s)...\n");
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "repository", &repoloc);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "repository", &repoloc))
+			return errno;
 		/*
 		 * Skip packages in local repositories.
 		 */
 		if (!xbps_check_is_repo_string_remote(repoloc))
 			continue;
 
-		prop_dictionary_get_cstring_nocopy(obj, "pkgver", &pkgver);
-		prop_dictionary_get_cstring_nocopy(obj, "filename", &filename);
-		prop_dictionary_get_cstring_nocopy(obj, "architecture", &arch);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgver", &pkgver))
+			return errno;
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "filename", &filename))
+			return errno;
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "architecture", &arch))
+			return errno;
 
 		repoloc_trans = xbps_get_remote_repo_string(repoloc);
 		if (repoloc_trans == NULL)
@@ -139,14 +154,12 @@ download_package_list(prop_object_iterator_t iter)
 			free(repoloc_trans);
 			return errno;
 		}
-
 		lbinfile = xbps_xasprintf("%s/%s", savedir, filename);
 		if (lbinfile == NULL) {
 			free(repoloc_trans);
 			free(savedir);
 			return errno;
 		}
-
 		if (access(lbinfile, R_OK) == 0) {
 			free(savedir);
 			free(lbinfile);
@@ -182,7 +195,10 @@ change_repodir:
 		if (savedir == NULL)
 		       return errno;
 
-		prop_dictionary_set_cstring(obj, "repository", savedir);
+		if (!prop_dictionary_set_cstring(obj, "repository", savedir)) {
+			free(savedir);
+			return errno;
+		}
 		free(savedir);
 	}
 	prop_object_iterator_reset(iter);
@@ -199,8 +215,12 @@ show_package_list(prop_object_iterator_t iter, const char *match)
 	bool first = false;
 
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgver", &pkgver);
-		prop_dictionary_get_cstring_nocopy(obj, "trans-action", &tract);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgver", &pkgver))
+			return;
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "trans-action", &tract))
+			return;
 		if (strcmp(match, tract))
 			continue;
 
@@ -233,17 +253,24 @@ show_transaction_sizes(prop_object_iterator_t iter)
 	 * installed and check the file hash.
 	 */
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_uint64(obj, "filename-size", &tsize);
+		if (!prop_dictionary_get_uint64(obj, "filename-size", &tsize))
+			return errno;
+
 		dlsize += tsize;
 		tsize = 0;
-		prop_dictionary_get_uint64(obj, "installed_size", &tsize);
+		if (!prop_dictionary_get_uint64(obj, "installed_size", &tsize))
+			return errno;
+
 		instsize += tsize;
 		tsize = 0;
 	}
 	prop_object_iterator_reset(iter);
 
 	while ((obj = prop_object_iterator_next(iter))) {
-		prop_dictionary_get_cstring_nocopy(obj, "trans-action", &tract);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "trans-action", &tract))
+			return errno;
+
 		if (strcmp(tract, "install") == 0)
 			trans_inst = true;
 		else if (strcmp(tract, "update") == 0)
@@ -384,8 +411,11 @@ xbps_exec_transaction(const char *pkgname, bool force, bool update)
 		goto out2;
 	}
 
-	prop_dictionary_get_cstring_nocopy(trans->dict,
-	     "origin", &trans->originpkgname);
+	if (!prop_dictionary_get_cstring_nocopy(trans->dict,
+	     "origin", &trans->originpkgname)) {
+		rv = errno;
+		goto out2;
+	}
 
 	if (update) {
 		/*
@@ -434,6 +464,9 @@ replace_packages(prop_object_iterator_t iter, const char *pkgver)
 	 */
 	while ((obj = prop_object_iterator_next(iter))) {
 		reppkgn = prop_string_cstring_nocopy(obj);
+		if (reppkgn == NULL)
+			return errno;
+
 		instd = xbps_find_pkg_installed_from_plist(reppkgn);
 		if (instd == NULL)
 			continue;
@@ -505,12 +538,22 @@ exec_transaction(struct transaction *trans)
 	 * Iterate over the transaction dictionary.
 	 */
 	while ((obj = prop_object_iterator_next(trans->iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);
-		prop_dictionary_get_cstring_nocopy(obj, "version", &version);
-		prop_dictionary_get_cstring_nocopy(obj, "pkgver", &pkgver);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgname", &pkgname))
+			return errno;
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "version", &version))
+			return errno;
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgver", &pkgver))
+			return errno;
 		prop_dictionary_get_bool(obj, "essential", &essential);
-		prop_dictionary_get_cstring_nocopy(obj, "filename", &filename);
-		prop_dictionary_get_cstring_nocopy(obj, "trans-action", &tract);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "filename", &filename))
+			return errno;
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "trans-action", &tract))
+			return errno;
 		replaces_iter = xbps_get_array_iter_from_dict(obj, "replaces");
 
 		/*
@@ -556,11 +599,17 @@ exec_transaction(struct transaction *trans)
 				return EINVAL;
 			}
 
-			prop_dictionary_get_cstring_nocopy(instpkgd,
-			    "version", &instver);
+			if (!prop_dictionary_get_cstring_nocopy(instpkgd,
+			    "version", &instver)) {
+				prop_object_release(instpkgd);
+				return errno;
+			}
 			autoinst = false;
-			prop_dictionary_get_bool(instpkgd, "automatic-install",
-			    &autoinst);
+			if (!prop_dictionary_get_bool(instpkgd,
+			    "automatic-install", &autoinst)) {
+				prop_object_release(instpkgd);
+				return errno;
+			}
 			prop_object_release(instpkgd);
 
 			/*
@@ -618,8 +667,12 @@ exec_transaction(struct transaction *trans)
 	 * Configure all unpacked packages.
 	 */
 	while ((obj = prop_object_iterator_next(trans->iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);
-		prop_dictionary_get_cstring_nocopy(obj, "version", &version);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgname", &pkgname))
+			return errno;
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "version", &version))
+			return errno;
 		if ((rv = xbps_configure_pkg(pkgname, version, false)) != 0) {
 			printf("Error configuring package %s (%s)\n",
 			    pkgname, strerror(rv));
diff --git a/bin/xbps-bin/remove.c b/bin/xbps-bin/remove.c
index ad6388da..3930a488 100644
--- a/bin/xbps-bin/remove.c
+++ b/bin/xbps-bin/remove.c
@@ -68,7 +68,11 @@ xbps_autoremove_pkgs(void)
 	printf("The following packages were installed automatically\n"
 	    "(as dependencies) and aren't needed anymore:\n\n");
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgver", &pkgver);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgver", &pkgver)) {
+			rv = errno;
+			goto out2;
+		}
 		cols += strlen(pkgver) + 4;
 		if (cols <= 80) {
 			if (first == false) {
@@ -90,8 +94,16 @@ xbps_autoremove_pkgs(void)
 	}
 
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);
-		prop_dictionary_get_cstring_nocopy(obj, "version", &version);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgname", &pkgname)) {
+			rv = errno;
+			goto out2;
+		}
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "version", &version)) {
+			rv = errno;
+			goto out;
+		}
 		printf("Removing package %s-%s ...\n", pkgname, version);
 		if ((rv = xbps_remove_pkg(pkgname, version, false)) != 0)
 			goto out2;
@@ -120,7 +132,8 @@ xbps_remove_installed_pkg(const char *pkgname, bool force)
 		printf("Package %s is not installed.\n", pkgname);
 		return 0;
 	}
-	prop_dictionary_get_cstring_nocopy(dict, "version", &version);
+	if (!prop_dictionary_get_cstring_nocopy(dict, "version", &version))
+		return errno;
 
 	reqby = prop_dictionary_get(dict, "requiredby");
 	if (reqby != NULL && prop_array_count(reqby) > 0) {
diff --git a/bin/xbps-repo/index.c b/bin/xbps-repo/index.c
index 23598832..03355884 100644
--- a/bin/xbps-repo/index.c
+++ b/bin/xbps-repo/index.c
@@ -61,10 +61,17 @@ repoidx_getdict(const char *pkgdir)
 			goto out;
 		}
 
-		prop_dictionary_set(dict, "packages", array);
+		if (!prop_dictionary_set(dict, "packages", array)) {
+			prop_object_release(dict);
+			prop_object_release(array);
+			goto out;
+		}
 		prop_object_release(array);
-		prop_dictionary_set_cstring_nocopy(dict,
-		    "pkgindex-version", XBPS_PKGINDEX_VERSION);
+		if (!prop_dictionary_set_cstring_nocopy(dict,
+		    "pkgindex-version", XBPS_PKGINDEX_VERSION)) {
+			prop_object_release(dict);
+			goto out;
+		}
 	}
 out:
 	free(plist);
@@ -128,10 +135,18 @@ xbps_repo_addpkg_index(prop_dictionary_t idxdict, const char *file)
 			break;
 		}
 
-		prop_dictionary_get_cstring_nocopy(newpkgd, "pkgname",
-		    &pkgname);
-		prop_dictionary_get_cstring_nocopy(newpkgd, "version",
-		    &version);
+		if (!prop_dictionary_get_cstring_nocopy(newpkgd, "pkgname",
+		    &pkgname)) {
+			prop_object_release(newpkgd);
+			rv = errno;
+			break;
+		}
+		if (!prop_dictionary_get_cstring_nocopy(newpkgd, "version",
+		    &version)) {
+			prop_object_release(newpkgd);
+			rv = errno;
+			break;
+		}
 		/*
 		 * Check if this package exists already in the index, but first
 		 * checking the version. If current package version is greater
@@ -140,8 +155,12 @@ xbps_repo_addpkg_index(prop_dictionary_t idxdict, const char *file)
 		 */
 		curpkgd = xbps_find_pkg_in_dict(idxdict, "packages", pkgname);
 		if (curpkgd) {
-			prop_dictionary_get_cstring_nocopy(curpkgd,
-			    "version", &regver);
+			if (!prop_dictionary_get_cstring_nocopy(curpkgd,
+			    "version", &regver)) {
+				prop_object_release(newpkgd);
+				rv = errno;
+				break;
+			}
 			if (xbps_cmpver(version, regver) <= 0) {
 				printf("W: skipping %s. %s-%s already "
 				    "registered.\n", filen, pkgname, regver);
@@ -167,14 +186,24 @@ xbps_repo_addpkg_index(prop_dictionary_t idxdict, const char *file)
 		 * We have the dictionary now, add the required
 		 * objects for the index.
 		 */
-		prop_dictionary_set_cstring(newpkgd, "filename", filen);
+		if (!prop_dictionary_set_cstring(newpkgd, "filename", filen)) {
+			prop_object_release(newpkgd);
+			rv = errno;
+			break;
+		}
 		sha256 = xbps_get_file_hash(file);
 		if (sha256 == NULL) {
 			prop_object_release(newpkgd);
 			rv = errno;
 			break;
 		}
-		prop_dictionary_set_cstring(newpkgd, "filename-sha256", sha256);
+		if (!prop_dictionary_set_cstring(newpkgd,
+		    "filename-sha256", sha256)) {
+			prop_object_release(newpkgd);
+			free(sha256);
+			rv = errno;
+			break;
+		}
 		free(sha256);
 
 		if (stat(file, &st) == -1) {
@@ -182,8 +211,12 @@ xbps_repo_addpkg_index(prop_dictionary_t idxdict, const char *file)
 			rv = errno;
 			break;
 		}
-		prop_dictionary_set_uint64(newpkgd, "filename-size",
-		    (uint64_t)st.st_size);
+		if (!prop_dictionary_set_uint64(newpkgd, "filename-size",
+		    (uint64_t)st.st_size)) {
+			prop_object_release(newpkgd);
+			rv = errno;
+			break;
+		}
 		/*
 		 * Add dictionary into the index and update package count.
 		 */
@@ -199,8 +232,13 @@ xbps_repo_addpkg_index(prop_dictionary_t idxdict, const char *file)
 			rv = EINVAL;
 			break;
 		}
-		prop_dictionary_set_uint64(idxdict, "total-pkgs",
-		    prop_array_count(pkgar));
+		if (!prop_dictionary_set_uint64(idxdict, "total-pkgs",
+		    prop_array_count(pkgar))) {
+			prop_object_release(newpkgd);
+			rv = errno;
+			break;
+		}
+		prop_object_release(newpkgd);
 		printf("Registered %s-%s in package index.\n",
 		    pkgname, version);
 		printf("\033[1A\033[K");
diff --git a/bin/xbps-repo/util.c b/bin/xbps-repo/util.c
index dc57139f..81433e1c 100644
--- a/bin/xbps-repo/util.c
+++ b/bin/xbps-repo/util.c
@@ -207,7 +207,12 @@ show_pkg_files_from_metadir(const char *pkgname)
 			goto out;
 		}
 		while ((obj = prop_object_iterator_next(iter))) {
-			prop_dictionary_get_cstring_nocopy(obj, "file", &file);
+			if (!prop_dictionary_get_cstring_nocopy(obj,
+			    "file", &file)) {
+				prop_object_iterator_release(iter);
+				rv = errno;
+				goto out;
+			}
 			printf("%s\n", file);
 		}
 		prop_object_iterator_release(iter);
@@ -230,7 +235,12 @@ show_pkg_files_from_metadir(const char *pkgname)
 			goto out;
 		}
 		while ((obj = prop_object_iterator_next(iter))) {
-			prop_dictionary_get_cstring_nocopy(obj, "file", &file);
+			if (!prop_dictionary_get_cstring_nocopy(obj,
+			    "file", &file)) {
+				prop_object_iterator_release(iter);
+				rv = errno;
+				goto out;
+			}
 			printf("%s\n", file);
 		}
 		prop_object_iterator_release(iter);
diff --git a/lib/configure.c b/lib/configure.c
index 624bb73c..c99a95e6 100644
--- a/lib/configure.c
+++ b/lib/configure.c
@@ -52,8 +52,16 @@ xbps_configure_all_pkgs(void)
 		return ENOENT;
 
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);
-		prop_dictionary_get_cstring_nocopy(obj, "version", &version);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgname", &pkgname)) {
+			rv = errno;
+			break;
+		}
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "version", &version)) {
+			rv = errno;
+			break;
+		}
 		if ((rv = xbps_get_pkg_state_dictionary(obj, &state)) != 0)
 			break;
 		if (state != XBPS_PKG_STATE_UNPACKED)
@@ -102,7 +110,11 @@ xbps_configure_pkg(const char *pkgname, const char *version, bool check_state)
 		if (pkgd == NULL)
 			return ENOENT;
 
-		prop_dictionary_get_cstring_nocopy(pkgd, "version", &lver);
+		if (!prop_dictionary_get_cstring_nocopy(pkgd,
+		    "version", &lver)) {
+			prop_object_release(pkgd);
+			return errno;
+		}
 		prop_object_release(pkgd);
 	} else {
 		lver = version;
diff --git a/lib/depends.c b/lib/depends.c
index d88fe40c..0b381abb 100644
--- a/lib/depends.c
+++ b/lib/depends.c
@@ -50,7 +50,8 @@ store_dependency(prop_dictionary_t master, prop_dictionary_t depd,
 	/*
 	 * Get some info about dependencies and current repository.
 	 */
-	prop_dictionary_get_cstring_nocopy(depd, "pkgname", &pkgname);
+	if (!prop_dictionary_get_cstring_nocopy(depd, "pkgname", &pkgname))
+		return errno;
 
 	dict = prop_dictionary_copy(depd);
 	if (dict == NULL)
@@ -84,7 +85,10 @@ store_dependency(prop_dictionary_t master, prop_dictionary_t depd,
 	/*
 	 * Add required objects into package dep's dictionary.
 	 */
-	prop_dictionary_set_cstring(dict, "repository", repoloc);
+	if (!prop_dictionary_set_cstring(dict, "repository", repoloc)) {
+		prop_object_release(dict);
+		return errno;
+	}
 	/*
 	 * Remove some unneeded objects.
 	 */
@@ -121,9 +125,14 @@ add_missing_reqdep(prop_dictionary_t master, const char *pkgname,
 		return errno;
 
 	missing_rdeps = prop_dictionary_get(master, "missing_deps");
-	prop_dictionary_set_cstring(mdepd, "pkgname", pkgname);
-	prop_dictionary_set_cstring(mdepd, "version", version);
-
+	if (!prop_dictionary_set_cstring(mdepd, "pkgname", pkgname)) {
+		prop_object_release(mdepd);
+		return errno;
+	}
+	if (!prop_dictionary_set_cstring(mdepd, "version", version)) {
+		prop_object_release(mdepd);
+		return errno;
+	}
 	if (!xbps_add_obj_to_array(missing_rdeps, mdepd)) {
 		prop_object_release(mdepd);
 		return EINVAL;
@@ -147,7 +156,9 @@ xbps_find_deps_in_pkg(prop_dictionary_t master, prop_dictionary_t pkg)
 	if (pkg_rdeps == NULL)
 		return 0;
 
-	prop_dictionary_get_cstring_nocopy(pkg, "pkgname", &pkgname);
+	if (!prop_dictionary_get_cstring_nocopy(pkg, "pkgname", &pkgname))
+		return errno;
+
 	DPRINTF(("Checking rundeps for %s.\n", pkgname));
 	/*
 	 * Iterate over the repository pool and find out if we have
@@ -213,6 +224,10 @@ find_repo_deps(prop_dictionary_t master, prop_dictionary_t repo,
 	 */
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
 		reqpkg = prop_string_cstring_nocopy(obj);
+		if (reqpkg == NULL) {
+			rv = EINVAL;
+			break;
+		}
 		/*
 		 * Check if required dep is satisfied and installed.
 		 */
diff --git a/lib/findpkg.c b/lib/findpkg.c
index f5db7576..8a6251af 100644
--- a/lib/findpkg.c
+++ b/lib/findpkg.c
@@ -156,6 +156,11 @@ xbps_prepare_repolist_data(void)
 		}
 
 		rdata->rd_uri = prop_string_cstring(obj);
+		if (rdata->rd_uri == NULL) {
+			free(plist);
+			rv = EINVAL;
+			goto out2;
+		}
 		rdata->rd_repod = prop_dictionary_internalize_from_file(plist);
 		if (rdata->rd_repod == NULL) {
 			free(plist);
@@ -225,7 +230,11 @@ xbps_find_new_packages(void)
 	 * installed packages.
 	 */
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgname", &pkgname)) {
+			rv = errno;
+			break;
+		}
 		rv = xbps_find_new_pkg(pkgname, obj);
 		if (rv == ENOENT)
 			continue;
@@ -276,10 +285,16 @@ xbps_find_new_pkg(const char *pkgname, prop_dictionary_t instpkg)
 			 * Check if version in repository is greater than
 			 * the version currently installed.
 			 */
-			prop_dictionary_get_cstring_nocopy(instpkg,
-			    "version", &instver);
-			prop_dictionary_get_cstring_nocopy(pkgrd,
-			    "version", &repover);
+			if (!prop_dictionary_get_cstring_nocopy(instpkg,
+			    "version", &instver)) {
+				rv = errno;
+				break;
+			}
+			if (!prop_dictionary_get_cstring_nocopy(pkgrd,
+			    "version", &repover)) {
+				rv = errno;
+				break;
+			}
 			if (xbps_cmpver(repover, instver) > 0) {
 				DPRINTF(("Found %s-%s in repo %s.\n",
 				    pkgname, repover, rdata->rd_uri));
@@ -307,7 +322,10 @@ xbps_find_new_pkg(const char *pkgname, prop_dictionary_t instpkg)
 	/*
 	 * Set repository in pkg dictionary.
 	 */
-	prop_dictionary_set_cstring(pkgrd, "repository", rdata->rd_uri);
+	if (!prop_dictionary_set_cstring(pkgrd, "repository", rdata->rd_uri)) {
+		rv = errno;
+		goto out;
+	}
 
 	/*
 	 * Construct the dependency chain for this package.
@@ -332,7 +350,11 @@ xbps_find_new_pkg(const char *pkgname, prop_dictionary_t instpkg)
 	if ((rv = set_pkg_state(pkgrd, pkgname)) != 0)
 		goto out;
 
-	prop_dictionary_set_cstring_nocopy(pkgrd, "trans-action", "update");
+	if (!prop_dictionary_set_cstring_nocopy(pkgrd,
+	    "trans-action", "update")) {
+		rv = errno;
+		goto out;
+	}
 
 	if (!prop_array_add(unsorted, pkgrd))
 		rv = errno;
@@ -405,8 +427,14 @@ xbps_prepare_pkg(const char *pkgname)
 	/*
 	 * Set repository in pkg dictionary.
 	 */
-	prop_dictionary_set_cstring(pkgrd, "repository", rdata->rd_uri);
-	prop_dictionary_set_cstring(pkg_props, "origin", pkgname);
+	if (!prop_dictionary_set_cstring(pkgrd, "repository", rdata->rd_uri)) {
+		rv = errno;
+		goto out;
+	}
+	if (!prop_dictionary_set_cstring(pkg_props, "origin", pkgname)) {
+		rv = errno;
+		goto out;
+	}
 
 	/*
 	 * Check if this package needs dependencies.
@@ -458,7 +486,11 @@ xbps_prepare_pkg(const char *pkgname)
 	if ((rv = set_pkg_state(pkgrd, pkgname)) != 0)
 		goto out;
 
-	prop_dictionary_set_cstring_nocopy(pkgrd, "trans-action", "install");
+	if (!prop_dictionary_set_cstring_nocopy(pkgrd,
+	    "trans-action", "install")) {
+		rv = errno;
+		goto out;
+	}
 
 	if (!prop_array_add(pkgs_array, pkgrd))
 		rv = errno;
diff --git a/lib/orphans.c b/lib/orphans.c
index bdc50619..48614ee7 100644
--- a/lib/orphans.c
+++ b/lib/orphans.c
@@ -83,6 +83,9 @@ find_orphan_pkg(prop_object_t obj, void *arg, bool *loop_done)
 
 	while ((obj2 = prop_object_iterator_next(iter)) != NULL) {
 		pkgname = xbps_get_pkg_name(prop_string_cstring_nocopy(obj2));
+		if (pkgname == NULL)
+			return EINVAL;
+
 		SIMPLEQ_FOREACH(orphan, &orphan_list, chain) {
 			if (strcmp(orphan->pkgname, pkgname) == 0) {
 				ndep++;
@@ -101,7 +104,11 @@ add_orphan:
 	if (orphan == NULL)
 		return errno;
 
-	prop_dictionary_get_cstring_nocopy(obj, "pkgname", &orphan->pkgname);
+	if (!prop_dictionary_get_cstring_nocopy(obj, "pkgname",
+	    &orphan->pkgname)) {
+		free(orphan);
+		return errno;
+	}
 	orphan->dict = prop_dictionary_copy(obj);
 	SIMPLEQ_INSERT_TAIL(&orphan_list, orphan, chain);
 
@@ -151,7 +158,10 @@ xbps_find_orphan_packages(void)
 		return NULL;
 	}
 	while ((orphan = SIMPLEQ_FIRST(&orphan_list)) != NULL) {
-		prop_array_add(array, orphan->dict);
+		if (!prop_array_add(array, orphan->dict)) {
+			cleanup();
+			return NULL;
+		}
 		SIMPLEQ_REMOVE(&orphan_list, orphan, orphan_pkg, chain);
 		prop_object_release(orphan->dict);
 		free(orphan);
diff --git a/lib/plist.c b/lib/plist.c
index 3dd355bb..aa121137 100644
--- a/lib/plist.c
+++ b/lib/plist.c
@@ -372,8 +372,11 @@ xbps_remove_pkg_from_dict(prop_dictionary_t dict, const char *key,
 
 	/* Iterate over the array of dictionaries to find its index. */
 	while ((obj = prop_object_iterator_next(iter))) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname",
-		    &curpkgname);
+		if (!prop_dictionary_get_cstring_nocopy(obj, "pkgname",
+		    &curpkgname)) {
+			prop_object_iterator_release(iter);
+			return errno;
+		}
 		if ((curpkgname && (strcmp(curpkgname, pkgname) == 0))) {
 			found = true;
 			break;
diff --git a/lib/purge.c b/lib/purge.c
index f69bcec7..53bad4c0 100644
--- a/lib/purge.c
+++ b/lib/purge.c
@@ -53,7 +53,11 @@ xbps_purge_all_pkgs(void)
 		return ENOENT;
 
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgname", &pkgname)) {
+			rv = errno;
+			break;
+		}
 		if ((rv = xbps_get_pkg_state_dictionary(obj, &state)) != 0)
 			break;
 		if (state != XBPS_PKG_STATE_CONFIG_FILES)
@@ -139,7 +143,12 @@ xbps_purge_pkg(const char *pkgname, bool check_state)
 			prop_object_release(dict);
 			return EINVAL;
 		}
-		prop_dictionary_get_cstring_nocopy(obj, "sha256", &sha256);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "sha256", &sha256)) {
+			prop_object_iterator_release(iter);
+			prop_object_release(dict);
+			return errno;
+		}
 		rv = xbps_check_file_hash(path, sha256);
 		if (rv == ENOENT) {
 			printf("Configuration file %s doesn't exist!\n", file);
diff --git a/lib/register.c b/lib/register.c
index 7401d33a..b44b7a2f 100644
--- a/lib/register.c
+++ b/lib/register.c
@@ -68,10 +68,30 @@ xbps_register_pkg(prop_dictionary_t pkgrd, bool automatic)
 			rv = ENOENT;
 			goto out;
 		}
-		prop_dictionary_set_cstring_nocopy(pkgd, "version", version);
-		prop_dictionary_set_cstring_nocopy(pkgd, "pkgver", pkgver);
-		prop_dictionary_set_cstring_nocopy(pkgd, "short_desc", desc);
-		prop_dictionary_set_bool(pkgd, "automatic-install", automatic);
+		if (!prop_dictionary_set_cstring_nocopy(pkgd,
+		    "version", version)) {
+			prop_object_release(pkgd);
+			rv = errno;
+			goto out;
+		}
+		if (!prop_dictionary_set_cstring_nocopy(pkgd,
+		    "pkgver", pkgver)) {
+			prop_object_release(pkgd);
+			rv = errno;
+			goto out;
+		}
+		if (!prop_dictionary_set_cstring_nocopy(pkgd,
+		    "short_desc", desc)) {
+			prop_object_release(pkgd);
+			rv = errno;
+			goto out;
+		}
+		if (!prop_dictionary_set_bool(pkgd,
+		    "automatic-install", automatic)) {
+			prop_object_release(pkgd);
+			rv = errno;
+			goto out;
+		}
 
 		/*
 		 * Add the requiredby objects for dependent packages.
diff --git a/lib/remove.c b/lib/remove.c
index ecaa1c09..ef9f5bbf 100644
--- a/lib/remove.c
+++ b/lib/remove.c
@@ -101,7 +101,12 @@ files:
 			prop_object_iterator_release(iter);
 			return EINVAL;
 		}
-		prop_dictionary_get_cstring_nocopy(obj, "sha256", &sha256);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "sha256", &sha256)) {
+			prop_object_iterator_release(iter);
+			free(path);
+			return errno;
+		}
 		rv = xbps_check_file_hash(path, sha256);
 		if (rv == ENOENT) {
 			printf("WARNING: '%s' doesn't exist!\n", file);
diff --git a/lib/requiredby.c b/lib/requiredby.c
index 09a1ac9a..a7eb7ae9 100644
--- a/lib/requiredby.c
+++ b/lib/requiredby.c
@@ -101,6 +101,11 @@ remove_pkg_from_reqby(prop_object_t obj, void *arg, bool *loop_done)
 	while ((obj2 = prop_object_iterator_next(iter)) != NULL) {
 		curpkgname =
 		    xbps_get_pkg_name(prop_string_cstring_nocopy(obj2));
+		if (curpkgname == NULL) {
+			prop_object_iterator_release(iter);
+			return EINVAL;
+		}
+			
 		if (strcmp(curpkgname, pkgname) == 0) {
 			free(curpkgname);
 			found = true;
@@ -157,7 +162,8 @@ xbps_requiredby_pkg_add(prop_array_t regar, prop_dictionary_t pkg)
 	char *rdepname;
 	int rv = 0;
 
-	prop_dictionary_get_cstring_nocopy(pkg, "pkgver", &pkgver);
+	if (!prop_dictionary_get_cstring_nocopy(pkg, "pkgver", &pkgver))
+		return errno;
 
 	rdeps = prop_dictionary_get(pkg, "run_depends");
 	if (rdeps == NULL || prop_array_count(rdeps) == 0)
@@ -169,7 +175,15 @@ xbps_requiredby_pkg_add(prop_array_t regar, prop_dictionary_t pkg)
 
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
 		str = prop_string_cstring_nocopy(obj);
+		if (str == NULL) {
+			rv = errno;
+			goto out;
+		}
 		rdepname = xbps_get_pkgdep_name(str);
+		if (rdepname == NULL) {
+			rv = EINVAL;
+			goto out;
+		}
 		iter2 = prop_array_iterator(regar);
 		if (iter2 == NULL) {
 			free(rdepname);
@@ -182,8 +196,13 @@ xbps_requiredby_pkg_add(prop_array_t regar, prop_dictionary_t pkg)
 		 * current run dependency.
 		 */
 		while ((obj2 = prop_object_iterator_next(iter2)) != NULL) {
-			prop_dictionary_get_cstring_nocopy(obj2, "pkgname",
-			    &reqname);
+			if (!prop_dictionary_get_cstring_nocopy(obj2,
+			    "pkgname", &reqname)) {
+				free(rdepname);
+				prop_object_iterator_release(iter2);
+				rv = errno;
+				goto out;
+			}
 			if (strcmp(rdepname, reqname) == 0) {
 				rv = add_pkg_into_reqby(obj2, pkgver);
 				if (rv == EEXIST)
diff --git a/lib/sortdeps.c b/lib/sortdeps.c
index 15457473..d7a3a770 100644
--- a/lib/sortdeps.c
+++ b/lib/sortdeps.c
@@ -80,9 +80,7 @@ xbps_sort_pkg_deps(prop_dictionary_t chaindeps)
 		prop_dictionary_set(chaindeps, "packages", sorted);
 		return 0;
 	}
-
 	ndeps = prop_array_count(unsorted);
-	unsorted = prop_dictionary_get(chaindeps, "unsorted_deps");
 
 	iter = prop_array_iterator(unsorted);
 	if (iter == NULL) {
@@ -94,7 +92,11 @@ again:
 	 * Order all deps by looking at its run_depends array.
 	 */
 	while ((obj = prop_object_iterator_next(iter)) != NULL) {
-		prop_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "pkgname", &pkgname)) {
+			rv = errno;
+			goto out;
+		}
 		if (find_sorteddep_by_name(pkgname) != NULL)
 			continue;
 
@@ -126,7 +128,17 @@ again:
 		 */
 		while ((obj2 = prop_object_iterator_next(iter2)) != NULL) {
 			str = prop_string_cstring_nocopy(obj2);
+			if (str == NULL) {
+				free(sdep);
+				rv = EINVAL;
+				goto out;
+			}
 			curpkgnamedep = xbps_get_pkgdep_name(str);
+			if (curpkgnamedep == NULL) {
+				free(sdep);
+				rv = EINVAL;
+				goto out;
+			}
 			/*
 			 * If dependency is already installed or queued,
 			 * pass to the next one.
@@ -163,7 +175,11 @@ again:
 	 * Add all sorted dependencies into the sorted deps array.
 	 */
 	while ((sdep = SIMPLEQ_FIRST(&sdep_list)) != NULL) {
-		prop_array_add(sorted, sdep->dict);
+		if (!prop_array_add(sorted, sdep->dict)) {
+			free(sdep);
+			rv = errno;
+			goto out;
+		}
 		SIMPLEQ_REMOVE(&sdep_list, sdep, sorted_dependency, chain);
 		prop_object_release(sdep->dict);
 		free(sdep);
diff --git a/lib/state.c b/lib/state.c
index 66e8a5cf..fa436ce3 100644
--- a/lib/state.c
+++ b/lib/state.c
@@ -72,8 +72,7 @@ get_state(prop_dictionary_t dict)
 
 	assert(dict != NULL);
 
-	prop_dictionary_get_cstring_nocopy(dict, "state", &state_str);
-	if (state_str == NULL)
+	if (!prop_dictionary_get_cstring_nocopy(dict, "state", &state_str))
 		return 0;
 
 	if (strcmp(state_str, "unpacked") == 0)
@@ -177,7 +176,12 @@ xbps_set_pkg_state_installed(const char *pkgname, pkg_state_t state)
 			rv = errno;
 			goto out;
 		}
-		prop_dictionary_set_cstring_nocopy(pkgd, "pkgname", pkgname);
+		if (!prop_dictionary_set_cstring_nocopy(pkgd, "pkgname",
+		    pkgname)) {
+			prop_object_release(array);
+			rv = errno;
+			goto out;
+		}
 		if ((rv = set_new_state(pkgd, state)) != 0) {
 			prop_object_release(array);
 			goto out;
@@ -198,8 +202,12 @@ xbps_set_pkg_state_installed(const char *pkgname, pkg_state_t state)
 		if (pkgd == NULL) {
 			newpkg = true;
 			pkgd = prop_dictionary_create();
-			prop_dictionary_set_cstring_nocopy(pkgd, "pkgname",
-			    pkgname);
+			if (!prop_dictionary_set_cstring_nocopy(pkgd,
+			    "pkgname", pkgname)) {
+				prop_object_release(pkgd);
+				rv = errno;
+				goto out;
+			}
 		}
 		array = prop_dictionary_get(dict, "packages");
 		if (array == NULL) {
diff --git a/lib/unpack.c b/lib/unpack.c
index 9c3656e3..e156499a 100644
--- a/lib/unpack.c
+++ b/lib/unpack.c
@@ -50,7 +50,9 @@ xbps_unpack_binary_pkg(prop_dictionary_t pkg, bool essential)
 	/*
 	 * Append filename to the full path for binary pkg.
 	 */
-	prop_dictionary_get_cstring_nocopy(pkg, "pkgname", &pkgname);
+	if (!prop_dictionary_get_cstring_nocopy(pkg, "pkgname", &pkgname))
+		return errno;
+
 	filename = prop_dictionary_get(pkg, "filename");
 	arch = prop_dictionary_get(pkg, "architecture");
 	repoloc = prop_dictionary_get(pkg, "repository");
@@ -172,8 +174,12 @@ install_config_file(prop_dictionary_t d, struct archive_entry *entry,
 	iter2 = xbps_get_array_iter_from_dict(forigd, "conf_files");
 	if (iter2 != NULL) {
 		while ((obj2 = prop_object_iterator_next(iter2))) {
-			prop_dictionary_get_cstring_nocopy(obj2,
-			    "file", &cffile);
+			if (!prop_dictionary_get_cstring_nocopy(obj2,
+			    "file", &cffile)) {
+				prop_object_iterator_release(iter2);
+				rv = errno;
+				goto out;
+			}
 			buf = xbps_xasprintf(".%s", cffile);
 			if (buf == NULL) {
 				prop_object_iterator_release(iter2);
@@ -204,7 +210,11 @@ install_config_file(prop_dictionary_t d, struct archive_entry *entry,
 	 * Compare original, installed and new hash for current file.
 	 */
 	while ((obj = prop_object_iterator_next(iter))) {
-		prop_dictionary_get_cstring_nocopy(obj, "file", &cffile);
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "file", &cffile)) {
+			prop_object_iterator_release(iter);
+			return errno;
+		}
 		buf = xbps_xasprintf(".%s", cffile);
 		if (buf == NULL) {
 			prop_object_iterator_release(iter);
@@ -217,8 +227,8 @@ install_config_file(prop_dictionary_t d, struct archive_entry *entry,
 		}
 		sha256_cur = xbps_get_file_hash(buf);
 		free(buf);
-		prop_dictionary_get_cstring_nocopy(obj, "sha256", &sha256_new);
-		if (sha256_new == NULL) {
+		if (!prop_dictionary_get_cstring_nocopy(obj,
+		    "sha256", &sha256_new)) {
 			rv = EINVAL;
 			break;
 		}
@@ -341,8 +351,10 @@ unpack_archive_fini(struct archive *ar, prop_dictionary_t pkg,
 	if (chdir(rootdir) == -1)
 		return errno;
 
-	prop_dictionary_get_cstring_nocopy(pkg, "pkgname", &pkgname);
-	prop_dictionary_get_cstring_nocopy(pkg, "version", &version);
+	if (!prop_dictionary_get_cstring_nocopy(pkg, "pkgname", &pkgname))
+		return errno;
+	if (!prop_dictionary_get_cstring_nocopy(pkg, "version", &version))
+		return errno;
 
 	while (archive_read_next_header(ar, &entry) == ARCHIVE_OK) {
 		entry_str = archive_entry_pathname(entry);
@@ -536,8 +548,16 @@ again:
 	while ((obj = prop_object_iterator_next(iter))) {
 		found = false;
 		oldstr = prop_dictionary_get(obj, "file");
+		if (oldstr == NULL) {
+			rv = errno;
+			goto out;
+		}
 		while ((obj2 = prop_object_iterator_next(iter2))) {
 			newstr = prop_dictionary_get(obj2, "file");
+			if (newstr == NULL) {
+				rv = errno;
+				goto out;
+			}
 			if (prop_string_equals(oldstr, newstr)) {
 				found = true;
 				break;