X-Git-Url: https://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftal%2Ftal.c;h=88bcb5ab6135257529eda0e999df024507c0386d;hp=474c0ff045c72f3f03c426851dc3e47ed365e4ba;hb=84b29c907c7608a024f65c4ef6803a1f5bb80ccd;hpb=f243444490e8dcdaa399942b70e72d03005370f7

diff --git a/ccan/tal/tal.c b/ccan/tal/tal.c
index 474c0ff0..88bcb5ab 100644
--- a/ccan/tal/tal.c
+++ b/ccan/tal/tal.c
@@ -9,6 +9,7 @@
 #include <stddef.h>
 #include <string.h>
 #include <limits.h>
+#include <errno.h>
 
 //#define TAL_DEBUG 1
 
@@ -482,6 +483,7 @@ static struct tal_hdr *remove_node(struct tal_hdr *t)
 void tal_free(const tal_t *ctx)
 {
         struct tal_hdr *t;
+	int saved_errno = errno;
 
         if (!ctx)
                 return;
@@ -489,6 +491,7 @@ void tal_free(const tal_t *ctx)
         t = debug_tal(to_tal_hdr(ctx));
         remove_node(t);
         del_tree(t);
+	errno = saved_errno;
 }
 
 void *tal_steal_(const tal_t *new_parent, const tal_t *ctx)
@@ -654,22 +657,29 @@ tal_t *tal_parent(const tal_t *ctx)
         return from_tal_hdr(group->parent_child->parent);
 }
 
-void *tal_realloc_(tal_t *ctx, size_t size)
+bool tal_resize_(tal_t **ctxp, size_t size)
 {
         struct tal_hdr *old_t, *t, **prev;
         struct group *group;
         struct children *child;
 
-        old_t = debug_tal(to_tal_hdr(ctx));
+        old_t = debug_tal(to_tal_hdr(*ctxp));
+
+	/* Don't hand silly sizes to realloc. */
+	if (size >> (CHAR_BIT*sizeof(size) - 1)) {
+		call_error("Reallocation size overflow");
+		return false;
+	}
 
         t = resizefn(old_t, size + sizeof(struct tal_hdr));
 	if (!t) {
 		call_error("Reallocation failure");
-		tal_free(old_t);
-		return NULL;
+		return false;
 	}
+
+	/* If it didn't move, we're done! */
         if (t == old_t)
-                return ctx;
+                return true;
 	update_bounds(t);
 
 	/* Fix up linked list pointer. */
@@ -689,13 +699,13 @@ void *tal_realloc_(tal_t *ctx, size_t size)
 		assert(child->parent == old_t);
 		child->parent = t;
 	}
-
-        return from_tal_hdr(debug_tal(t));
+	*ctxp = from_tal_hdr(debug_tal(t));
+	return true;
 }
 
 char *tal_strdup(const tal_t *ctx, const char *p)
 {
-	return tal_memdup(ctx, p, strlen(p)+1);
+	return tal_dup(ctx, char, p, strlen(p)+1, 0);
 }
 
 char *tal_strndup(const tal_t *ctx, const char *p, size_t n)
@@ -704,20 +714,35 @@ char *tal_strndup(const tal_t *ctx, const char *p, size_t n)
 
 	if (strlen(p) < n)
 		n = strlen(p);
-	ret = tal_memdup(ctx, p, n+1);
+	ret = tal_dup(ctx, char, p, n, 1);
 	if (ret)
 		ret[n] = '\0';
 	return ret;
 }
 
-void *tal_memdup(const tal_t *ctx, const void *p, size_t n)
+void *tal_dup_(const tal_t *ctx, const void *p, size_t n, size_t extra,
+	       const char *label)
 {
 	void *ret;
 
-	if (ctx == TAL_TAKE)
-		return (void *)p;
+	/* Beware overflow! */
+	if (n + extra < n || n + extra + sizeof(struct tal_hdr) < n) {
+		call_error("dup size overflow");
+		if (ctx == TAL_TAKE)
+			tal_free(p);
+		return NULL;
+	}
 
-	ret = tal_arr(ctx, char, n);
+	if (ctx == TAL_TAKE) {
+		if (unlikely(!p))
+			return NULL;
+		if (!tal_resize_((void **)&p, n + extra)) {
+			tal_free(p);
+			return NULL;
+		}
+		return (void *)p;
+	}
+	ret = tal_alloc_(ctx, n + extra, false, label);
 	if (ret)
 		memcpy(ret, p, n);
 	return ret;
@@ -755,7 +780,10 @@ char *tal_vasprintf(const tal_t *ctx, const char *fmt, va_list ap)
 
 		if (ret < max)
 			break;
-		buf = tal_resize(buf, max *= 2);
+		if (!tal_resize(&buf, max *= 2)) {
+			tal_free(buf);
+			buf = NULL;
+		}
 	}
 	if (ctx == TAL_TAKE)
 		tal_free(fmt);