checkout: do not make a temporary copy of symlink target.

If the index records an insanely long symbolic link, copying
into the temporary would overflow the buffer (noticed by Mark
Wooding).

Because read_sha1_file() terminates the returned buffer with NUL
since late May 2005, there is no reason to copy it anymore.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/entry.c b/entry.c
index 410b758..6c47c3a 100644 (file)
--- a/entry.c
+++ b/entry.c
@@ -70,7 +70,6 @@ static int write_entry(struct cache_entry *ce, const char *path, struct checkout
        unsigned long size;
        long wrote;
        char type[20];
-       char target[1024];
 
        new = read_sha1_file(ce->sha1, type, &size);
        if (!new || strcmp(type, "blob")) {
@@ -94,12 +93,10 @@ static int write_entry(struct cache_entry *ce, const char *path, struct checkout
                        return error("git-checkout-index: unable to write file %s", path);
                break;
        case S_IFLNK:
-               memcpy(target, new, size);
-               target[size] = '\0';
-               if (symlink(target, path)) {
+               if (symlink(new, path)) {
                        free(new);
-                       return error("git-checkout-index: unable to create symlink %s (%s)",
-                               path, strerror(errno));
+                       return error("git-checkout-index: unable to create "
+                                    "symlink %s (%s)", path, strerror(errno));
                }
                free(new);
                break;