diff options
| -rw-r--r-- | lib/ChangeLog | 7 | ||||
| -rw-r--r-- | lib/calloc.c | 10 | ||||
| -rw-r--r-- | lib/malloc.c | 2 | ||||
| -rw-r--r-- | lib/realloc.c | 15 | ||||
| -rw-r--r-- | m4/ChangeLog | 5 | ||||
| -rw-r--r-- | m4/calloc.m4 | 35 |
6 files changed, 57 insertions, 17 deletions
diff --git a/lib/ChangeLog b/lib/ChangeLog index 8fc22f032..64bc023f1 100644 --- a/lib/ChangeLog +++ b/lib/ChangeLog @@ -1,3 +1,10 @@ +2004-11-17 Paul Eggert <eggert@cs.ucla.edu> + + * realloc.c (rpl_realloc): Call 'free' if n==0, since realloc + might fail. Problem reported by Yoann Vandoorselaere. + * calloc.c (rpl_calloc): Defend against buggy calloc implementations + that mishandle size_t overflow. + 2004-11-16 Paul Eggert <eggert@cs.ucla.edu> * xgetcwd.c: Include <limits.h>, for PATH_MAX. diff --git a/lib/calloc.c b/lib/calloc.c index 2a9e6fa20..1ff0f1c0b 100644 --- a/lib/calloc.c +++ b/lib/calloc.c @@ -1,4 +1,4 @@ -/* Work around the condition whereby calloc (n, s) fails when n*s is 0. +/* calloc() function that is glibc compatible. This wrapper function is required at least on Tru64 UNIX 5.1. Copyright (C) 2004 Free Software Foundation, Inc. @@ -31,9 +31,17 @@ void * rpl_calloc (size_t n, size_t s) { + size_t bytes; if (n == 0) n = 1; if (s == 0) s = 1; + + /* Defend against buggy calloc implementations that mishandle + size_t overflow. */ + bytes = n * s; + if (bytes / s != n) + return NULL; + return calloc (n, s); } diff --git a/lib/malloc.c b/lib/malloc.c index a43d16927..ca04c57cd 100644 --- a/lib/malloc.c +++ b/lib/malloc.c @@ -1,4 +1,4 @@ -/* Work around bug on some systems where malloc (0) fails. +/* malloc() function that is glibc compatible. Copyright (C) 1997, 1998 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify diff --git a/lib/realloc.c b/lib/realloc.c index ccbf99138..14fec075f 100644 --- a/lib/realloc.c +++ b/lib/realloc.c @@ -1,5 +1,5 @@ -/* Work around bug on some systems where realloc (NULL, 0) fails. - Copyright (C) 1997, 2003 Free Software Foundation, Inc. +/* realloc() function that is glibc compatible. + Copyright (C) 1997, 2003, 2004 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -32,8 +32,15 @@ void * rpl_realloc (void *p, size_t n) { if (n == 0) - n = 1; - if (p == 0) + { + n = 1; + + /* In theory realloc might fail, so don't rely on it to free. */ + free (p); + p = NULL; + } + + if (p == NULL) return malloc (n); return realloc (p, n); } diff --git a/m4/ChangeLog b/m4/ChangeLog index 6b030b204..6cd8f6a15 100644 --- a/m4/ChangeLog +++ b/m4/ChangeLog @@ -1,3 +1,8 @@ +2004-11-17 Paul Eggert <eggert@cs.ucla.edu> + + * calloc.m4 (_AC_FUNC_CALLOC_IF): Check for buggy calloc implementations + that mishandle size_t overflow. + 2004-11-16 Paul Eggert <eggert@cs.ucla.edu> * canon-host.m4 (gl_CANON_HOST): Check for getaddrinfo. diff --git a/m4/calloc.m4 b/m4/calloc.m4 index 5d03ed271..f244df7b2 100644 --- a/m4/calloc.m4 +++ b/m4/calloc.m4 @@ -1,6 +1,25 @@ -#serial 2 +# calloc.m4 serial 3 -# Determine whether calloc (N, S) returns non-NULL when N*S is zero. +# Copyright (C) 2004 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2, or (at your option) +# any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software Foundation, +# Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +# Written by Jim Meyering. + +# Determine whether calloc (N, S) returns non-NULL when N*S is zero, +# and returns NULL when N*S overflows. # If so, define HAVE_CALLOC. Otherwise, define calloc to rpl_calloc # and arrange to use a calloc wrapper function that does work in that case. @@ -9,17 +28,11 @@ # If `calloc (0, 0)' is properly handled, run IF-WORKS, otherwise, IF-NOT. AC_DEFUN([_AC_FUNC_CALLOC_IF], [AC_REQUIRE([AC_HEADER_STDC])dnl +AC_REQUIRE([AC_TYPE_SIZE_T])dnl AC_CHECK_HEADERS(stdlib.h) AC_CACHE_CHECK([for GNU libc compatible calloc], ac_cv_func_calloc_0_nonnull, -[AC_RUN_IFELSE( -[AC_LANG_PROGRAM( -[[#if STDC_HEADERS || HAVE_STDLIB_H -# include <stdlib.h> -#else -char *calloc (); -#endif -]], - [exit (calloc (0, 0) ? 0 : 1);])], +[AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT], + [exit (!calloc (0, 0) || calloc ((size_t) -1 / 8 + 1, 8));])], [ac_cv_func_calloc_0_nonnull=yes], [ac_cv_func_calloc_0_nonnull=no], [ac_cv_func_calloc_0_nonnull=no])]) |