add_packed_git: convert strcpy into xsnprintf
We have the path "foo.idx", and we create a buffer big enough to hold "foo.pack" and "foo.keep", and then strcpy straight into it. This isn't a bug (we have enough space), but it's very hard to tell from the strcpy that this is so. Let's instead use strip_suffix to take off the ".idx", record the size of our allocation, and use xsnprintf to make sure we don't violate our assumptions. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Jeff King committed
Sep 24, 2015 at 17:06 UTC
48bcc1c3cc09db1a6da0ce47460fae6e5f7edd4b
2 files changed
+14
-9
cache.h
+1
-1
@@ -1309,7 +1309,7 @@ extern void close_pack_windows(struct packed_git *);
1309
extern void unuse_pack(struct pack_window **);
1310
extern void free_pack_by_name(const char *);
1311
extern void clear_delta_base_cache(void);
1312
-extern struct packed_git *add_packed_git(const char *, int, int);
1312
+extern struct packed_git *add_packed_git(const char *path, size_t path_len, int local);
1313
1314
/*
1315
* Return the SHA-1 of the nth object within the specified packfile.
sha1_file.c
+13
-8
@@ -1146,11 +1146,12 @@ static void try_to_free_pack_memory(size_t size)
1146
release_pack_memory(size);
1147
}
1148
1149
-struct packed_git *add_packed_git(const char *path, int path_len, int local)
1149
+struct packed_git *add_packed_git(const char *path, size_t path_len, int local)
1150
{
1151
static int have_set_try_to_free_routine;
1152
struct stat st;
1153
- struct packed_git *p = alloc_packed_git(path_len + 2);
1153
+ size_t alloc;
1154
+ struct packed_git *p;
1155
1156
if (!have_set_try_to_free_routine) {
1157
have_set_try_to_free_routine = 1;
@@ -1161,18 +1162,22 @@ struct packed_git *add_packed_git(const char *path, int path_len, int local)
1162
* Make sure a corresponding .pack file exists and that
1163
* the index looks sane.
1164
*/
1164
- path_len -= strlen(".idx");
1165
- if (path_len < 1) {
1166
- free(p);
1165
+ if (!strip_suffix_mem(path, &path_len, ".idx"))
1166
return NULL;
1168
- }
1167
+
1168
+ /*
1169
+ * ".pack" is long enough to hold any suffix we're adding (and
1170
+ * the use xsnprintf double-checks that)
1171
+ */
1172
+ alloc = path_len + strlen(".pack") + 1;
1173
+ p = alloc_packed_git(alloc);
1174
memcpy(p->pack_name, path, path_len);
1175
1171
- strcpy(p->pack_name + path_len, ".keep");
1176
+ xsnprintf(p->pack_name + path_len, alloc - path_len, ".keep");
1177
if (!access(p->pack_name, F_OK))
1178
p->pack_keep = 1;
1179
1175
- strcpy(p->pack_name + path_len, ".pack");
1180
+ xsnprintf(p->pack_name + path_len, alloc - path_len, ".pack");
1181
if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) {
1182
free(p);
1183
return NULL;