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From: "ulfalizer at gmail dot com" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sourceware.org
Subject: [Bug libc/2753] Integer overflow in bsearch
Date: Thu, 13 Nov 2014 10:13:00 -0000	[thread overview]
Message-ID: <bug-2753-131-2PPJrmegvo@http.sourceware.org/bugzilla/> (raw)
In-Reply-To: <bug-2753-131@http.sourceware.org/bugzilla/>

https://sourceware.org/bugzilla/show_bug.cgi?id=2753

Ulf Magnusson <ulfalizer at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
                 CC|                            |ulfalizer at gmail dot com
         Resolution|WORKSFORME                  |---

--- Comment #5 from Ulf Magnusson <ulfalizer at gmail dot com> ---
For what it's worth, here's a test case that causes bsearch() to hang when
sizeof(size_t) == 4:


#include <stdlib.h>
#include <string.h>

#define LEN 0x80000001

static int compar(const void *a, const void *b) {
    return *(char*)a - *(char*)b;
}

int main() {
    char *arr = malloc(LEN), key = 1;
    memset(arr, 0, LEN);
    bsearch(&key, arr, LEN, 1, compar);
}


The bug could be fixed by replacing '__idx = (__l + __u) / 2' with '__idx = __l
+ (__u - __l)/2' in bits/stdlib-bsearch.h. I don't see a good reason not to.

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       reply	other threads:[~2014-11-13 10:13 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-2753-131@http.sourceware.org/bugzilla/>
2014-11-13 10:13 ` ulfalizer at gmail dot com [this message]
2014-11-13 10:17 ` ulfalizer at gmail dot com
2014-11-25 21:54 ` neleai at seznam dot cz
2015-04-27 19:45 ` wbrad.vt at gmail dot com
2006-06-10 20:38 [Bug libc/2753] New: " greenrd at greenrd dot org
2006-06-13 15:27 ` [Bug libc/2753] " drepper at redhat dot com
2006-06-13 15:29 ` drepper at redhat dot com
2006-06-13 17:45 ` greenrd at greenrd dot org
2006-08-12 20:33 ` drepper at redhat dot com

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