diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/interfaces/libpq/pqexpbuffer.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/src/interfaces/libpq/pqexpbuffer.c b/src/interfaces/libpq/pqexpbuffer.c index 0396f7a6b37..6aef4cf94de 100644 --- a/src/interfaces/libpq/pqexpbuffer.c +++ b/src/interfaces/libpq/pqexpbuffer.c @@ -17,13 +17,15 @@ * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/interfaces/libpq/pqexpbuffer.c,v 1.16 2003/11/29 19:52:12 pgsql Exp $ + * $PostgreSQL: pgsql/src/interfaces/libpq/pqexpbuffer.c,v 1.17 2004/05/14 00:20:38 tgl Exp $ * *------------------------------------------------------------------------- */ #include "postgres_fe.h" +#include <limits.h> + #include "pqexpbuffer.h" #ifdef WIN32 @@ -132,7 +134,18 @@ enlargePQExpBuffer(PQExpBuffer str, size_t needed) size_t newlen; char *newdata; + /* + * Guard against ridiculous "needed" values, which can occur if we're + * fed bogus data. Without this, we can get an overflow or infinite + * loop in the following. + */ + if (needed >= ((size_t) INT_MAX - str->len)) + return 0; + needed += str->len + 1; /* total space required now */ + + /* Because of the above test, we now have needed <= INT_MAX */ + if (needed <= str->maxlen) return 1; /* got enough space already */ @@ -146,6 +159,14 @@ enlargePQExpBuffer(PQExpBuffer str, size_t needed) while (needed > newlen) newlen = 2 * newlen; + /* + * Clamp to INT_MAX in case we went past it. Note we are assuming + * here that INT_MAX <= UINT_MAX/2, else the above loop could + * overflow. We will still have newlen >= needed. + */ + if (newlen > (size_t) INT_MAX) + newlen = (size_t) INT_MAX; + newdata = (char *) realloc(str->data, newlen); if (newdata != NULL) { |