Re: [PATCH 1/3] prune-packed: fix a possible buffer overflow
Duy Nguyen <pclouds@gmail.com> writes:
> Why don't we take this opportunity to replace that array with a
> strbuf? The conversion looks simple with this function.
Indeed. Something like this, perhaps?
builtin/prune-packed.c | 38 +++++++++++++++++++++-----------------
1 file changed, 21 insertions(+), 17 deletions(-)
diff --git a/builtin/prune-packed.c b/builtin/prune-packed.c
index fa6ce42..fcf5fb6 100644
--- a/builtin/prune-packed.c
+++ b/builtin/prune-packed.c
@@ -10,58 +10,62 @@ static const char * const prune_packed_usage[] = {
static struct progress *progress;
-static void prune_dir(int i, DIR *dir, char *pathname, int len, int opts)
+static void prune_dir(int i, DIR *dir, struct strbuf *pathname, int opts)
{
struct dirent *de;
char hex[40];
+ int top_len = pathname->len;
sprintf(hex, "%02x", i);
while ((de = readdir(dir)) != NULL) {
unsigned char sha1[20];
if (strlen(de->d_name) != 38)
continue;
- memcpy(hex+2, de->d_name, 38);
+ memcpy(hex + 2, de->d_name, 38);
if (get_sha1_hex(hex, sha1))
continue;
if (!has_sha1_pack(sha1))
continue;
- memcpy(pathname + len, de->d_name, 38);
+
+ strbuf_add(pathname, de->d_name, 38);
if (opts & PRUNE_PACKED_DRY_RUN)
- printf("rm -f %s\n", pathname);
+ printf("rm -f %s\n", pathname->buf);
else
- unlink_or_warn(pathname);
+ unlink_or_warn(pathname->buf);
display_progress(progress, i + 1);
+ strbuf_setlen(pathname, top_len);
}
}
void prune_packed_objects(int opts)
{
int i;
- static char pathname[PATH_MAX];
const char *dir = get_object_directory();
- int len = strlen(dir);
+ struct strbuf pathname = STRBUF_INIT;
+ int top_len;
+ strbuf_addstr(&pathname, dir);
if (opts & PRUNE_PACKED_VERBOSE)
progress = start_progress_delay("Removing duplicate objects",
256, 95, 2);
- if (len > PATH_MAX - 42)
- die("impossible object directory");
- memcpy(pathname, dir, len);
- if (len && pathname[len-1] != '/')
- pathname[len++] = '/';
+ if (pathname.len && pathname.buf[pathname.len - 1] != '/')
+ strbuf_addch(&pathname, '/');
+
+ top_len = pathname.len;
for (i = 0; i < 256; i++) {
DIR *d;
display_progress(progress, i + 1);
- sprintf(pathname + len, "%02x/", i);
- d = opendir(pathname);
+ strbuf_setlen(&pathname, top_len);
+ strbuf_addf(&pathname, "%02x/", i);
+ d = opendir(pathname.buf);
if (!d)
continue;
- prune_dir(i, d, pathname, len + 3, opts);
+ prune_dir(i, d, &pathname, opts);
closedir(d);
- pathname[len + 2] = '\0';
- rmdir(pathname);
+ strbuf_setlen(&pathname, top_len + 2);
+ rmdir(pathname.buf);
}
stop_progress(&progress);
}
Junio C Hamano <gitster@pobox.com>