Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

more complete solution for gethostby*() buffer overwrite issue.

Browse Source 
(we need thread-safe gethostby*...)
This commit is contained in:
itojun 1999-12-13 17:05:45 +00:00
parent 43aa150a4e
commit 72e7091f16
1 changed files with 36 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
lib/libc/net/getaddrinfo.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: getaddrinfo.c,v 1.15 1999/12/13 16:22:56 itojun Exp $ */
/* $NetBSD: getaddrinfo.c,v 1.16 1999/12/13 17:05:45 itojun Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@ -514,9 +514,13 @@ explore_fqdn(pai, hostname, servname, res)
struct hostent *hp;
int h_error;
int af;
char *ap = NULL;
char **aplist = NULL, *apbuf = NULL;
char *ap;
struct addrinfo sentinel, *cur;
int i;
#ifndef USE_GETIPNODEBY
int naddrs;
#endif
const struct afd *afd;
int error;
@ -582,19 +586,37 @@ explore_fqdn(pai, hostname, servname, res)
if (hp == NULL)
goto free;
ap = malloc(hp->h_length);
if (ap == NULL) {
#ifdef USE_GETIPNODEBY
aplist = hp->h_addr_list;
#else
/*
* hp will be overwritten if we use gethostbyname2().
* always deep copy for simplification.
*/
for (naddrs = 0; hp->h_addr_list[naddrs] != NULL; naddrs++)
;
naddrs++;
aplist = (char **)malloc(sizeof(aplist[0]) * naddrs);
apbuf = (char *)malloc(hp->h_length * naddrs);
if (aplist == NULL || apbuf == NULL) {
error = EAI_MEMORY;
goto free;
}
memset(aplist, 0, sizeof(aplist[0]) * naddrs);
for (i = 0; i < naddrs; i++) {
if (hp->h_addr_list[i] == NULL) {
aplist[i] = NULL;
continue;
}
memcpy(&apbuf[i * hp->h_length], hp->h_addr_list[i],
hp->h_length);
aplist[i] = &apbuf[i * hp->h_length];
}
#endif
for (i = 0; hp->h_addr_list[i] != NULL; i++) {
/*
* hp will be overwritten if we use gethostbyname2().
* always deep copy for simplification.
*/
for (i = 0; aplist[i] != NULL; i++) {
af = hp->h_addrtype;
memcpy(ap, hp->h_addr_list[i], hp->h_length);
ap = aplist[i];
if (af == AF_INET6
&& IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) {
af = AF_INET;
@ -635,8 +657,10 @@ free:
if (hp)
freehostent(hp);
#endif
if (ap)
free(ap);
if (aplist)
free(aplist);
if (apbuf)
free(apbuf);
if (sentinel.ai_next)
freeaddrinfo(sentinel.ai_next);
return error;