From: Felix Fietkau <nbd@openwrt.org>
Date: Fri, 21 Oct 2011 13:13:32 +0000 (+0200)
Subject: add a few missing null pointer checks, and fix check vs dereference order in some... 
X-Git-Url: http://git.archive.openwrt.org/?p=project%2Fuci.git;a=commitdiff_plain;h=1d6095d5ac6482672dbb434b8df7c5de69b9d64e

add a few missing null pointer checks, and fix check vs dereference order in some cases (patch by Stanislav Fomichev)
---

diff --git a/cli.c b/cli.c
index cfbf261..54f9484 100644
--- a/cli.c
+++ b/cli.c
@@ -450,7 +450,7 @@ static int uci_do_section_cmd(int cmd, int argc, char **argv)
 		ret = uci_add_list(ctx, &ptr);
 		break;
 	case CMD_REORDER:
-		if (!ptr.s) {
+		if (!ptr.s || !ptr.value) {
 			ctx->err = UCI_ERR_NOTFOUND;
 			cli_perror();
 			return 1;
diff --git a/file.c b/file.c
index 0530eb2..4eb35b1 100644
--- a/file.c
+++ b/file.c
@@ -619,7 +619,7 @@ int uci_import(struct uci_context *ctx, FILE *stream, const char *name, struct u
 	uci_alloc_parse_context(ctx);
 	pctx = ctx->pctx;
 	pctx->file = stream;
-	if (*package && single) {
+	if (package && *package && single) {
 		pctx->package = *package;
 		pctx->merge = true;
 	}
diff --git a/libuci.c b/libuci.c
index 995d39d..4c2bf96 100644
--- a/libuci.c
+++ b/libuci.c
@@ -177,7 +177,7 @@ uci_get_errorstr(struct uci_context *ctx, char **dest, const char *prefix)
 	if (dest) {
 		err = asprintf(dest, format,
 			(prefix ? prefix : ""), (prefix ? ": " : ""),
-			(ctx->func ? ctx->func : ""), (ctx->func ? ": " : ""),
+			(ctx && ctx->func ? ctx->func : ""), (ctx && ctx->func ? ": " : ""),
 			uci_errstr[err],
 			error_info);
 		if (err < 0)
@@ -186,7 +186,7 @@ uci_get_errorstr(struct uci_context *ctx, char **dest, const char *prefix)
 		strcat(error_info, "\n");
 		fprintf(stderr, format,
 			(prefix ? prefix : ""), (prefix ? ": " : ""),
-			(ctx->func ? ctx->func : ""), (ctx->func ? ": " : ""),
+			(ctx && ctx->func ? ctx->func : ""), (ctx && ctx->func ? ": " : ""),
 			uci_errstr[err],
 			error_info);
 	}
diff --git a/list.c b/list.c
index fabad4d..cf6d970 100644
--- a/list.c
+++ b/list.c
@@ -485,7 +485,7 @@ static void uci_add_element_list(struct uci_context *ctx, struct uci_ptr *ptr, b
 int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr)
 {
 	/* NB: UCI_INTERNAL use means without delta tracking */
-	bool internal = ctx->internal;
+	bool internal = ctx && ctx->internal;
 	struct uci_element *e;
 	struct uci_package *p;
 	char *n;
@@ -530,7 +530,7 @@ int uci_reorder_section(struct uci_context *ctx, struct uci_section *s, int pos)
 
 int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res)
 {
-	bool internal = ctx->internal;
+	bool internal = ctx && ctx->internal;
 	struct uci_section *s;
 
 	UCI_HANDLE_ERR(ctx);
@@ -547,7 +547,7 @@ int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *
 int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr)
 {
 	/* NB: pass on internal flag to uci_del_element */
-	bool internal = ctx->internal;
+	bool internal = ctx && ctx->internal;
 	struct uci_package *p;
 	struct uci_element *e;
 
@@ -574,7 +574,7 @@ int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr)
 int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr)
 {
 	/* NB: UCI_INTERNAL use means without delta tracking */
-	bool internal = ctx->internal;
+	bool internal = ctx && ctx->internal;
 	struct uci_option *prev = NULL;
 	const char *value2 = NULL;
 
@@ -615,7 +615,7 @@ int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr)
 int uci_set(struct uci_context *ctx, struct uci_ptr *ptr)
 {
 	/* NB: UCI_INTERNAL use means without delta tracking */
-	bool internal = ctx->internal;
+	bool internal = ctx && ctx->internal;
 
 	UCI_HANDLE_ERR(ctx);
 	uci_expand_ptr(ctx, ptr, false);
diff --git a/uci_internal.h b/uci_internal.h
index e0c4204..02f81f5 100644
--- a/uci_internal.h
+++ b/uci_internal.h
@@ -186,9 +186,9 @@ struct uci_backend _var = {		\
 #define UCI_HANDLE_ERR(ctx) do {	\
 	DPRINTF("ENTER: %s\n", __func__); \
 	int __val = 0;			\
-	ctx->err = 0;			\
 	if (!ctx)			\
 		return UCI_ERR_INVAL;	\
+	ctx->err = 0;			\
 	if (!ctx->internal && !ctx->nested) \
 		__val = setjmp(ctx->trap); \
 	ctx->internal = false;		\
diff --git a/ucimap-example.c b/ucimap-example.c
index e04c66d..18c3c1f 100644
--- a/ucimap-example.c
+++ b/ucimap-example.c
@@ -132,6 +132,8 @@ static struct ucimap_section_data *
 network_allocate(struct uci_map *map, struct uci_sectionmap *sm, struct uci_section *s)
 {
 	struct uci_network *p = malloc(sizeof(struct uci_network));
+	if (!p)
+		return NULL;
 	memset(p, 0, sizeof(struct uci_network));
 	return &p->map;
 }
@@ -244,6 +246,8 @@ int main(int argc, char **argv)
 
 	INIT_LIST_HEAD(&ifs);
 	ctx = uci_alloc_context();
+	if (!ctx)
+		return -1;
 	ucimap_init(&network_map);
 
 	if ((argc >= 2) && !strcmp(argv[1], "-s")) {
diff --git a/ucimap.c b/ucimap.c
index 6a5c117..0bc31c5 100644
--- a/ucimap.c
+++ b/ucimap.c
@@ -295,6 +295,9 @@ realloc:
 		offset = (items - (*list)->size) * sizeof(union ucimap_data);
 
 	a->ptr = realloc(a->ptr, size);
+	if (!a->ptr)
+		return -ENOMEM;
+
 	if (offset)
 		memset((char *) a->ptr + offset, 0, size - offset);
 	new = a->ptr;