Revision 447ac906e189535e77dcb1f4bbe3f1bc917d4c12 authored by Patrick Steinhardt on 01 December 2022, 14:45:31 UTC, committed by Junio C Hamano on 05 December 2022, 06:14:16 UTC
The `struct attr_stack` tracks the stack of all patterns together with their attributes. When parsing a gitattributes file that has more than 2^31 such patterns though we may trigger multiple out-of-bounds reads on 64 bit platforms. This is because while the `num_matches` variable is an unsigned integer, we always use a signed integer to iterate over them. I have not been able to reproduce this issue due to memory constraints on my systems. But despite the out-of-bounds reads, the worst thing that can seemingly happen is to call free(3P) with a garbage pointer when calling `attr_stack_free()`. Fix this bug by using unsigned integers to iterate over the array. While this makes the iteration somewhat awkward when iterating in reverse, it is at least better than knowingly running into an out-of-bounds read. While at it, convert the call to `ALLOC_GROW` to use `ALLOC_GROW_BY` instead. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 34ace8b
url.c
#include "cache.h"
#include "url.h"
int is_urlschemechar(int first_flag, int ch)
{
/*
* The set of valid URL schemes, as per STD66 (RFC3986) is
* '[A-Za-z][A-Za-z0-9+.-]*'. But use slightly looser check
* of '[A-Za-z0-9][A-Za-z0-9+.-]*' because earlier version
* of check used '[A-Za-z0-9]+' so not to break any remote
* helpers.
*/
int alphanumeric, special;
alphanumeric = ch > 0 && isalnum(ch);
special = ch == '+' || ch == '-' || ch == '.';
return alphanumeric || (!first_flag && special);
}
int is_url(const char *url)
{
/* Is "scheme" part reasonable? */
if (!url || !is_urlschemechar(1, *url++))
return 0;
while (*url && *url != ':') {
if (!is_urlschemechar(0, *url++))
return 0;
}
/* We've seen "scheme"; we want colon-slash-slash */
return (url[0] == ':' && url[1] == '/' && url[2] == '/');
}
static char *url_decode_internal(const char **query, int len,
const char *stop_at, struct strbuf *out,
int decode_plus)
{
const char *q = *query;
while (len) {
unsigned char c = *q;
if (!c)
break;
if (stop_at && strchr(stop_at, c)) {
q++;
len--;
break;
}
if (c == '%' && (len < 0 || len >= 3)) {
int val = hex2chr(q + 1);
if (0 < val) {
strbuf_addch(out, val);
q += 3;
len -= 3;
continue;
}
}
if (decode_plus && c == '+')
strbuf_addch(out, ' ');
else
strbuf_addch(out, c);
q++;
len--;
}
*query = q;
return strbuf_detach(out, NULL);
}
char *url_decode(const char *url)
{
return url_decode_mem(url, strlen(url));
}
char *url_decode_mem(const char *url, int len)
{
struct strbuf out = STRBUF_INIT;
const char *colon = memchr(url, ':', len);
/* Skip protocol part if present */
if (colon && url < colon) {
strbuf_add(&out, url, colon - url);
len -= colon - url;
url = colon;
}
return url_decode_internal(&url, len, NULL, &out, 0);
}
char *url_percent_decode(const char *encoded)
{
struct strbuf out = STRBUF_INIT;
return url_decode_internal(&encoded, strlen(encoded), NULL, &out, 0);
}
char *url_decode_parameter_name(const char **query)
{
struct strbuf out = STRBUF_INIT;
return url_decode_internal(query, -1, "&=", &out, 1);
}
char *url_decode_parameter_value(const char **query)
{
struct strbuf out = STRBUF_INIT;
return url_decode_internal(query, -1, "&", &out, 1);
}
void end_url_with_slash(struct strbuf *buf, const char *url)
{
strbuf_addstr(buf, url);
strbuf_complete(buf, '/');
}
void str_end_url_with_slash(const char *url, char **dest)
{
struct strbuf buf = STRBUF_INIT;
end_url_with_slash(&buf, url);
free(*dest);
*dest = strbuf_detach(&buf, NULL);
}
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...