From: Linus Torvalds <torvalds@ppc970.osdl.org>
Date: Fri, 20 May 2005 14:49:17 +0000 (-0700)
Subject: fsck-cache: fix segfault on nonexistent referenced object
X-Git-Tag: v0.99~530
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=7c4d07c7cc8543f1000639dc19cfaacbc76e5348;p=git.git

fsck-cache: fix segfault on nonexistent referenced object

Noted by Frank Sorenson and Petr Baudis, patch rewritten by me.
---

diff --git a/fsck-cache.c b/fsck-cache.c
index 32fa5d53e..6c65f2bb2 100644
--- a/fsck-cache.c
+++ b/fsck-cache.c
@@ -296,7 +296,7 @@ static int fsck_dir(int i, char *path)
 	return 0;
 }
 
-static void read_sha1_reference(const char *path)
+static int read_sha1_reference(const char *path)
 {
 	char hexname[60];
 	unsigned char sha1[20];
@@ -304,19 +304,23 @@ static void read_sha1_reference(const char *path)
 	struct object *obj;
 
 	if (fd < 0)
-		return;
+		return -1;
 
 	len = read(fd, hexname, sizeof(hexname));
 	close(fd);
 	if (len < 40)
-		return;
+		return -1;
 
 	if (get_sha1_hex(hexname, sha1) < 0)
-		return;
+		return -1;
 
 	obj = lookup_object(sha1);
+	if (!obj)
+		return error("%s: invalid sha1 pointer %.40s", path, hexname);
+
 	obj->used = 1;
 	mark_reachable(obj, REACHABLE);
+	return 0;
 }
 
 static void find_file_objects(const char *base, const char *name)