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Bounds checking - Wikipedia, the free encyclopedia In computer programming, bounds checking is the name given to any method of detecting whether or not an index given lies within the limits of an array. Because performing bounds checking during every access of an array is inefficient and in some applications unacceptable, there are compiler technologies for eliminating bounds checking in many common cases when they are provably not needed; see bounds checking elimination. The D programming language has run time bounds checking that is enabled or disabled with a compiler switch. en.wikipedia.org /wiki/Bounds_checking   (386 words)

Program-semantics Aware Intrusion Detection The minimum number of instruction required to check a reference in a C-like application against its lower and upper bounds is 6, two to load the bounds, tow comparisons, and two conditional branches. Cash (Checking Array bounds using Segmentation Hardware) is a GCC extension that uses the segmentation hardware of Intel’s X86 architecture to automatically check the bounds when an array is accessed. Recognizing the similarity between segment bounds checking and array bounds checking, Cash allocates a separate segment to each array, and generates the array reference instructions in such a way that X86 architecture’s segment bounds checking hardware effectively performs the required array bounds checking for free. www.ecsl.cs.sunysb.edu /cash   (585 words)

Bounds Checking for C Bounds checking is easy for arrays because the array subscript syntax specifies both the address calculation and the array within which the resulting pointer should point. A third more-or-less workable scheme is to modify the representation of pointers to include three items: the pointer itself, and the lower and upper bounds of the object to which it is supposed to point. We can check whether a pointer arithmetic expression is valid by finding its base pointer's storage region, then checking that the expression's result points into the same storage region. www-ala.doc.ic.ac.uk /~phjk/BoundsChecking.html   (937 words)

[No title] At the moment, the bounds checking changes are specific to the C front end, so you can't use them with the other GCC front ends (eg. Bounds checking GCC does not attempt to detect memory leaks, nor is it capable of garbage collection. In addition, the variable `__bounds_checking_on' is set to 1 when bounds checking is on in the program as a whole, and set to 0 when it is not. www.mit.edu /afs/sipb/project/bounds/info/gcc.info-10   (4790 words)

Network Theory Ltd - Memory bounds-checking for GCC The bounds checking extension to GCC provides a way of detecting invalid memory accesses, by producing additional checking instructions for each read or write in the executable file. The initial bounds checking patch for gcc was developed by Richard Jones and Paul Kelly of the Department of Computer Science, Imperial College (London) in 1995. Bounds Checking is free software, and you are welcome to redistribute it under certain conditions. www.network-theory.co.uk /articles/boundschecking.html   (727 words)

Comp.compilers: eliminating array bounds checking overhead Re: eliminating array bounds checking overhead rhyde@shoe-size.com (Randall Hyde) (2000-04-27) Re: eliminating array bounds checking overhead fjscipio@rochester.rr.com (Fred J. Scipione) (2000-04-27) Re: eliminating array bounds checking overhead markw65@my-deja.com (Mark Williams) (2000-04-30) compilers.iecc.com /comparch/article/00-04-194   (271 words)

Local Use of Compiler Features Array bounds checking provides a check of most array references at both compile time and run time to ensure that each subscript is within the array's declared size. Bounds checking is needed when very large values are used to calculate addresses for memory references. If bounds checking detects an out-of-bounds array reference, a message is issued for only the first out-of-bounds array reference in the loop. docs.cray.com /books/S-3901-51/html-S-3901-51/zfixed4ftzi5op.html   (566 words)

[No title]   (Site not responding. Last check: 2007-09-07) Check implementation on installation, or limit the size of all string inputs. Perform bounds checking, use functions that limit length, or ensure that the size is larger than the maximum possible length. /tmp/audit.9463/sendmail-8.13.1/editmap/editmap.c:208: [2] (misc) fopen: Check when opening files - can an attacker redirect it (via symlinks), force the opening of special file type (e.g., device files), move things around to create a race condition, control its ancestors, or change its contents?. dev.gentoo.org /~tigger/audit/sendmail_8_13_1_tar_gz_flawfinder   (15855 words)

Array bounds checking (Henry Spencer) The reason is clear: such checks are expensive, particularly with a naive compiler that can't eliminate many of them at compile time, and the overrun condition is rare. One negative aspect of having hardware and languages that enforce checking is that you have no control over the tradeoffs. The remaining 1% might require a way to tell the compiler "believe me, it's right", but otherwise the need for a run-time check could be made a fatal compile-time error. yarchive.net /comp/array_bounds_check.html   (539 words)

GCC extensions - GNU Project - Free Software Foundation (FSF) This is an experimental port of GCC to the DEC PDP-10 architecture. Bounds checking patches for GCC releases and GCC snapshots You may freely mix object modules compiled with and without bounds checking. gcc.gnu.org /extensions.html   (351 words)

Digital Mars - D - array bounds checking question. Digital Mars - D - array bounds checking question. Array bounds checking is on in debug builds by default. checking of for certain pieces of code, it would also be desirable to be www.digitalmars.com /d/archives/8343.html   (898 words)

Untitled Debugging with GDB: You may debug bounds checked programs with GDB and there are special breakpoints for this purpose. Bounds checking will then consider this to be a flat array with 9 elements. Bounds checking GCC can't currently check this, but it may well be added in a future version. www.lrde.epita.fr /~akim/compil/doc/bounds-checking.html   (2419 words)

Bounds Checking   (Site not responding. Last check: 2007-09-07) Both input and output should be checked for validity For many coordinate frameworks, the mathematical formulation may exist everywhere even though the results may be nonsensical for some regions Determining acceptable bounds requires an examination of distortion effects and, in some cases, computational accuracy www.sedris.org /stc/2001/tu/srm/sld144.htm   (62 words)

David Hayden : for and foreach loops - Compiler Optimizations Regarding Bounds Checking He briefly mentioned some of the optimizations done by the compiler regarding for loops and bounds checking in Arrays. It determines that this loop will never attempt to access an element not bounded by the array and thus emits a more performant loop that either reduces or eliminates the bounds checking. It used to be, in.NET 1.0, that the foreach loop was less performant than the for loop, but this isn't the case anymore. codebetter.com /blogs/david.hayden/archive/2005/02/27/56104.aspx   (587 words)

I thought that array bounds checking needed two comparisons;   (Site not responding. Last check: 2007-09-07) I thought that array bounds checking needed two comparisons; Only that array bounds checking is done by the JVM, which is The bounds checking is neither written in Java nor in byte code. javaquestions.org /ftopic11109.html   (991 words)

I thought that array bounds checking needed two comparisons; however, ... - Java @ 24help.info it newsgroups   (Site not responding. Last check: 2007-09-07) I thought that array bounds checking needed two comparisons; however,... Re: I thought that array bounds checking needed two comparisons;however,... Re: I thought that array bounds checking needed two comparisons; however,... www.24help.info /showthread.php?t=28323   (370 words)

gcc bounds checking, valgrind, purify Checking out those links, it appears that these patches are very much like a static version of Valgrind. Valgrind works dynamically with an x86 code rewriter that appears to be language independent and seems to implement a lot of the difficult functionality that the original Purify implemented. that ran slowly but did a lot of checking. www.mail-archive.com /cygwin@cygwin.com/msg48899.html   (319 words)

24help.info - I thought that array bounds checking needed two comparisons; however, ...   (Site not responding. Last check: 2007-09-07) - - I thought that array bounds checking needed two comparisons; however,... 06-03-2004 10:13 PM I thought that array bounds checking needed two comparisons; however,... 06-04-2004 04:46 AM Re: I thought that array bounds checking needed two comparisons;however,... www.24help.info /printthread.php?t=28323   (377 words)

Flawfinder Results viewer/commandproc.cpp:67: [2] (misc) fopen: Check when opening files - can an attacker redirect it (via symlinks), force the opening of special file type (e.g., device files), move things around to create a race condition, control its ancestors, or change its contents?. viewer/commandproc.cpp:70: [2] (misc) fopen: Check when opening files - can an attacker redirect it (via symlinks), force the opening of special file type (e.g., device files), move things around to create a race condition, control its ancestors, or change its contents?. viewer/commandproc.h:72: [2] (misc) fopen: Check when opening files - can an attacker redirect it (via symlinks), force the opening of special file type (e.g., device files), move things around to create a race condition, control its ancestors, or change its contents?. lx-viewer.sourceforge.net /flawfinder_report.html   (4226 words)

Comp.compilers: Re: eliminating array bounds checking overhead element := a(i); -- no range checking needed, i is in range by definition a(j); -- range checking not needed, j is within Index by definition a(k); -- range checking needed due possibility of k being outside of Index compilers.iecc.com /comparch/article/00-04-202   (301 words)

Trustix: tcpdump incorrect bounds checking vulnerability - The Community's Center for Security In the decoding of BGP packages, it failed to do proper bounds checking. The impact is not known, but it could at least be used to crash tcpdump. Check out our mailing lists: http://www.trustix.net/support/ Verification: This advisory along with all TSL packages are signed with the TSL sign key. www.linuxsecurity.com /content/view/104437/109   (501 words)

Digital Mars - D - array bounds checking A secondary bounded pointer type should be defined for that purpose. against the upper and lower bounds of the array, and an exception is thrown errors in C are caused by improper array bounds checking. www.digitalmars.com /d/archives/2781.html   (5259 words)

dBforums - Interesting change in "bounds checking" checking is turned on, then one ONLY gets a "boundary violation" In all of our compilers you *can* defeat bounds checking very simply, but by It is only with bounds checking *reset* that you can "alias" elements of a www.dbforums.com /t704190.html   (3218 words)

dBforums - digital visual fortran: array bounds checking > to turn the array bounds checking on. If using the IDE, /check is on by default. that is taken as /check:all, so you get ALL the run-time checks. www.dbforums.com /t727184.html   (145 words)

Sanjay's Coding Tips :: CCured: Bounds Checking for C CCured: Bounds Checking for C [Other Coding] - Posted @ 03:24 pm: PermLink CCured is a source-to-source translator for C, which analyzes the program to determine the smallest number of run-time checks that must be inserted in the program to prevent all memory safety violations. Think of it as bounds checking for C that's fast. sastools.com /b2/post/79393893   (135 words)

Find in a Library: Low cost array bounds checking for 64-bit architectures Find in a Library: Low cost array bounds checking for 64-bit architectures Low cost array bounds checking for 64-bit architectures WorldCat is provided by OCLC Online Computer Library Center, Inc. on behalf of its member libraries. worldcatlibraries.org /wcpa/ow/004111474791e20ea19afeb4da09e526.html   (64 words)

SourceForge.net: Project Info - boundschecking This package adds full, fine-grained array bounds and pointer checking to GCC (C only). The level of checking is similar to, and in some respects exceeds, that of languages like Pascal and Modula-2. This project has not yet categorized itself in the Trove Software Map. sourceforge.net /projects/boundschecking   (117 words)

SecurityTracker.com Archives - Linux Kernel mremap() Improper Bounds Checking Lets Local Users Gain Root Privileges A local user can reportedly cause the kernel to remap memory and create a virtual memory area that is 0 bytes in length. An incorrect bound check discovered inside the do_mremap() kernel code performing remapping of a virtual memory area may lead to creation of a virtual memory area of 0 bytes length. The problem bases on the general mremap flaw that remapping of 2 pages from inside a VMA creates a memory hole of only one page in length but an additional VMA of two pages. www.securitytracker.com /alerts/2004/Jan/1008593.html   (1389 words)

[No title] /tmp/ccXZ90ln.o /usr/lib/gcc/i686-pc-linux-gnu/3.4.2/libboundscheck.a -lgcc -lgcc_eh -lc -lgcc -lgcc_eh /usr/lib/gcc/i686-pc-linux-gnu/3.4.2/crtendS.o /usr/lib/gcc/i686-pc-linux-gnu/3.4.2/../../../crtn.o solar@simple vuln $./vuln AAAAAAAAA Bounds Checking GCC v gcc-3.4.2-3.2 Copyright (C) 1995 Richard W.M. Jones Bounds Checking comes with ABSOLUTELY NO WARRANTY. Control runtime behaviour: -array-index-check *Check the index of all array references. -no-array-index-check Only check the pointer is within the array. dev.gentoo.org /~solar/hardened/boundscheck.txt   (364 words)

Bounds Checking in C & C++ using Bounded Pointers - GNU Project - Free Software Foundation (FSF)   (Site not responding. Last check: 2007-09-07) Bounds Checking in C and C++ using Bounded Pointers - GNU Project - Free Software Foundation (FSF) Please send FSF and GNU inquiries and questions to gnu@gnu.org. Verbatim copying and distribution of this entire article is permitted in any medium, provided this notice is preserved. gcc.gnu.org /projects/bp/main.html   (124 words)

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