asprintf related fixed in yy parser

1. According to man asprintf:
   If memory allocation wasn't possible, or some other error occurs,
   these functions will return -1, and the contents of strp is undefined.
2. Sometimes, errp was not filled at all. In high-level code, free(errp)
   will called, so segmantation fault may appear in case of error in parser
3. The most cases of using asprintf is to report about allocation fail.
   So, probability of allocation of asprintf buffer is very high. And that
   will lead to trash in errp.
4. For simple casses I decide to replace asprintf with strdup

1 files changed, 14 insertions, 10 deletions

diff --git a/lib/route/cls/ematch_syntax.y b/lib/route/cls/ematch_syntax.y
index 61c91d1..39123be 100644
--- a/lib/route/cls/ematch_syntax.y
+++ b/lib/route/cls/ematch_syntax.y
@@ -53,7 +53,9 @@ extern int ematch_lex(YYSTYPE *, void *);
 static void yyerror(void *scanner, char **errp, struct nl_list_head *root, const char *msg)
 {
 	if (msg)
-		asprintf(errp, "%s", msg);
+            *errp = strdup(msg);
+        else
+	    *errp = NULL;
 }
 %}
 
@@ -186,7 +188,7 @@ ematch:
 			struct rtnl_ematch *e;
 
 			if (!(e = rtnl_ematch_alloc())) {
-				asprintf(errp, "Unable to allocate ematch object");
+				*errp = strdup("Unable to allocate ematch object");
 				YYABORT;
 			}
 
@@ -201,7 +203,7 @@ ematch:
 			struct rtnl_ematch *e;
 
 			if (!(e = rtnl_ematch_alloc())) {
-				asprintf(errp, "Unable to allocate ematch object");
+				*errp = strdup("Unable to allocate ematch object");
 				YYABORT;
 			}
 
@@ -219,7 +221,7 @@ ematch:
 			struct rtnl_ematch *e;
 
 			if (!(e = rtnl_ematch_alloc())) {
-				asprintf(errp, "Unable to allocate ematch object");
+				*errp = strdup("Unable to allocate ematch object");
 				YYABORT;
 			}
 
@@ -246,7 +248,7 @@ ematch:
 			struct rtnl_ematch *e;
 
 			if (!(e = rtnl_ematch_alloc())) {
-				asprintf(errp, "Unable to allocate ematch object");
+				*errp = strdup("Unable to allocate ematch object");
 				YYABORT;
 			}
 
@@ -265,7 +267,7 @@ ematch:
 			struct rtnl_ematch *e;
 
 			if (!(e = rtnl_ematch_alloc())) {
-				asprintf(errp, "Unable to allocate ematch object");
+				*errp = strdup("Unable to allocate ematch object");
 				YYABORT;
 			}
 
@@ -417,7 +419,8 @@ pattern:
 				memcpy($$.data, nl_addr_get_binary_addr(addr), $$.len);
 				nl_addr_put(addr);
 			} else {
-				asprintf(errp, "invalid pattern \"%s\"", $1);
+				if (asprintf(errp, "invalid pattern \"%s\"", $1) == -1)
+					*errp = NULL;
 				YYABORT;
 			}
 		}
@@ -433,7 +436,8 @@ pktloc:
 			struct rtnl_pktloc *loc;
 
 			if (rtnl_pktloc_lookup($1, &loc) < 0) {
-				asprintf(errp, "Packet location \"%s\" not found", $1);
+				if (asprintf(errp, "Packet location \"%s\" not found", $1) == -1)
+					*errp = NULL;
 				YYABORT;
 			}
 
@@ -445,12 +449,12 @@ pktloc:
 			struct rtnl_pktloc *loc;
 
 			if ($5 && (!$1 || $1 > TCF_EM_ALIGN_U32)) {
-				asprintf(errp, "mask only allowed for alignments u8|u16|u32");
+				*errp = strdup("mask only allowed for alignments u8|u16|u32");
 				YYABORT;
 			}
 
 			if (!(loc = rtnl_pktloc_alloc())) {
-				asprintf(errp, "Unable to allocate packet location object");
+				*errp = strdup("Unable to allocate packet location object");
 				YYABORT;
 			}