From: Jeff King <peff@peff.net>
Date: Wed, 27 Sep 2017 06:02:21 +0000 (-0400)
Subject: worktree: use xsize_t to access file size
X-Git-Tag: v2.15.0-rc0~19^2~1
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/228740b67b55f4ee23637bd1472a73ae50efe93a?hp=--cc

worktree: use xsize_t to access file size

To read the "gitdir" file into memory, we stat the file and
allocate a buffer. But we store the size in an "int", which
may be truncated. We should use a size_t and xsize_t(),
which will detect truncation.

An overflow is unlikely for a "gitdir" file, but it's a good
practice to model.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

228740b67b55f4ee23637bd1472a73ae50efe93a
diff --git a/builtin/worktree.c b/builtin/worktree.c
index de26849f55..2f4a4ef9cd 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -38,7 +38,8 @@ static int prune_worktree(const char *id, struct strbuf *reason)
 {
 	struct stat st;
 	char *path;
-	int fd, len;
+	int fd;
+	size_t len;
 
 	if (!is_directory(git_path("worktrees/%s", id))) {
 		strbuf_addf(reason, _("Removing worktrees/%s: not a valid directory"), id);
@@ -56,7 +57,7 @@ static int prune_worktree(const char *id, struct strbuf *reason)
 			    id, strerror(errno));
 		return 1;
 	}
-	len = st.st_size;
+	len = xsize_t(st.st_size);
 	path = xmallocz(len);
 	read_in_full(fd, path, len);
 	close(fd);