diff options
Diffstat (limited to 'resolv/nss_dns/dns-network.c')
| -rw-r--r-- | resolv/nss_dns/dns-network.c | 43 |
1 files changed, 29 insertions, 14 deletions
diff --git a/resolv/nss_dns/dns-network.c b/resolv/nss_dns/dns-network.c index 97d9263895..4552b5b678 100644 --- a/resolv/nss_dns/dns-network.c +++ b/resolv/nss_dns/dns-network.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1996, 1997, 1998, 1999, 2002, 2004 +/* Copyright (C) 1996, 1997, 1998, 1999, 2002, 2004, 2007 Free Software Foundation, Inc. This file is part of the GNU C Library. Extended from original form by Ulrich Drepper <drepper@cygnus.com>, 1996. @@ -102,7 +102,8 @@ extern int __ns_name_unpack (const u_char *, const u_char *, /* Prototypes for local functions. */ static enum nss_status getanswer_r (const querybuf *answer, int anslen, struct netent *result, char *buffer, - size_t buflen, lookup_method net_i); + size_t buflen, int *errnop, int *h_errnop, + lookup_method net_i); enum nss_status @@ -142,7 +143,8 @@ _nss_dns_getnetbyname_r (const char *name, struct netent *result, ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND; } - status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen, BYNAME); + status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen, + errnop, herrnop, BYNAME); if (net_buffer.buf != orig_net_buffer) free (net_buffer.buf); return status; @@ -218,7 +220,8 @@ _nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result, ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND; } - status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen, BYADDR); + status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen, + errnop, herrnop, BYADDR); if (net_buffer.buf != orig_net_buffer) free (net_buffer.buf); if (status == NSS_STATUS_SUCCESS) @@ -240,7 +243,8 @@ _nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result, static enum nss_status getanswer_r (const querybuf *answer, int anslen, struct netent *result, - char *buffer, size_t buflen, lookup_method net_i) + char *buffer, size_t buflen, int *errnop, int *h_errnop, + lookup_method net_i) { /* * Find first satisfactory answer @@ -260,8 +264,25 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, { char *aliases[MAX_NR_ALIASES]; char linebuffer[0]; - } *net_data = (struct net_data *) buffer; + } *net_data; + + uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct net_data); + buffer += pad; + + if (__builtin_expect (buflen < sizeof (*net_data) + pad, 0)) + { + /* The buffer is too small. */ + too_small: + *errnop = ERANGE; + *h_errnop = NETDB_INTERNAL; + return NSS_STATUS_TRYAGAIN; + } + buflen -= pad; + + net_data = (struct net_data *) buffer; int linebuflen = buflen - offsetof (struct net_data, linebuffer); + if (buflen - offsetof (struct net_data, linebuffer) != linebuflen) + linebuflen = INT_MAX; const unsigned char *end_of_message = &answer->buf[anslen]; const HEADER *header_pointer = &answer->hdr; /* #/records in the answer section. */ @@ -319,10 +340,7 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1) { if (errno == EMSGSIZE) - { - errno = ERANGE; - return NSS_STATUS_TRYAGAIN; - } + goto too_small; n = -1; } @@ -346,10 +364,7 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1) { if (errno == EMSGSIZE) - { - errno = ERANGE; - return NSS_STATUS_TRYAGAIN; - } + goto too_small; n = -1; } |