0071-proc/readproc.c: Harden supgrps_from_supgids().

1/ Prevent an integer overflow of t.

2/ Avoid an infinite loop if s contains characters other than comma,
spaces, +, -, and digits.

3/ Handle all possible return values of snprintf().

---------------------------- adapted for newlib branch
. we can't use xrealloc(), so we use realloc() instead
. and must account for a mem failure via a return of 1

Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit is contained in:
Qualys Security Advisory 1970-01-01 00:00:00 +00:00 committed by Craig Small
parent 807498f899
commit ec0cb25af6

View File

@ -478,11 +478,25 @@ static int supgrps_from_supgids (proc_t *p) {
s = p->supgid;
t = 0;
do {
if (',' == *s) ++s;
g = pwcache_get_group((uid_t)strtol(s, &s, 10));
if (!(p->supgrp = realloc(p->supgrp, P_G_SZ+t+2)))
const int max = P_G_SZ+2;
char *end = NULL;
gid_t gid;
int len;
while (',' == *s) ++s;
gid = strtol(s, &end, 10);
if (end <= s) break;
s = end;
g = pwcache_get_group(gid);
if ((t >= INT_MAX - max)
|| (!(p->supgrp = realloc(p->supgrp, t + max))))
return 1;
t += snprintf(p->supgrp+t, P_G_SZ+2, "%s%s", t ? "," : "", g);
len = snprintf(p->supgrp+t, max, "%s%s", t ? "," : "", g);
if (len <= 0) (p->supgrp+t)[len = 0] = '\0';
else if (len >= max) len = max-1;
t += len;
} while (*s);
return 0;