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From: Andreas Schwab <schwab@redhat.com>
To: libc-hacker@sourceware.org
Subject: [PATCH] Don't read past end of buffer in fmemopen
Date: Thu, 03 Mar 2011 13:08:00 -0000	[thread overview]
Message-ID: <m3oc5s1hds.fsf@redhat.com> (raw)

The buffer is not required to contain a zero byte at all.

Andreas.

2011-03-03  Andreas Schwab  <schwab@redhat.com>

	* libio/fmemopen.c (fmemopen): Don't read past end of buffer.
---
 libio/fmemopen.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/libio/fmemopen.c b/libio/fmemopen.c
index d3750fc..1a631d5 100644
--- a/libio/fmemopen.c
+++ b/libio/fmemopen.c
@@ -1,5 +1,5 @@
 /* Fmemopen implementation.
-   Copyright (C) 2000, 2002, 2005, 2006, 2008, 2009
+   Copyright (C) 2000, 2002, 2005, 2006, 2008, 2009, 2011
    Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Hanno Mueller, kontakt@hanno.de, 2000.
@@ -243,7 +243,7 @@ fmemopen (void *buf, size_t len, const char *mode)
   if (mode[0] == 'w')
     c->buffer[0] = '\0';
 
-  c->maxpos = strlen (c->buffer);
+  c->maxpos = strnlen (c->buffer, len);
 
   if (mode[0] == 'a')
     c->pos = c->maxpos;
-- 
1.7.4


-- 
Andreas Schwab, schwab@redhat.com
GPG Key fingerprint = D4E8 DBE3 3813 BB5D FA84  5EC7 45C6 250E 6F00 984E
"And now for something completely different."

                 reply	other threads:[~2011-03-03 13:08 UTC|newest]

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