{"id":476585,"date":"2023-08-09T07:31:20","date_gmt":"2023-08-09T07:31:20","guid":{"rendered":""},"modified":"2023-09-05T11:13:02","modified_gmt":"2023-09-05T11:13:02","slug":"dangling-pointer","status":"publish","type":"wiki","link":"https:\/\/oneproxy.pro\/tr\/wiki\/dangling-pointer\/","title":{"rendered":"Sarkan i\u015faret\u00e7i"},"content":{"rendered":"<p>Sarkan i\u015faret\u00e7i, bilgisayar programlamada \u00e7ok \u00f6nemli bir kavramd\u0131r ve \u00f6zellikle C ve C++ gibi d\u00fc\u015f\u00fck seviyeli dillerle ilgilidir. Program bu konumdaki belle\u011fe eri\u015fmeye \u00e7al\u0131\u015ft\u0131\u011f\u0131nda beklenmedik ve potansiyel olarak tehlikeli davran\u0131\u015flara yol a\u00e7an, tahsisi kald\u0131r\u0131lm\u0131\u015f veya serbest b\u0131rak\u0131lm\u0131\u015f bir bellek konumuna i\u015faret eden bir i\u015faret\u00e7iyi ifade eder. Sarkan i\u015faret\u00e7ileri anlamak ve y\u00f6netmek, g\u00fcvenli ve sa\u011flam bir yaz\u0131l\u0131m yazmak i\u00e7in \u00e7ok \u00f6nemlidir.<\/p>\n<h2>Sarkan \u0130\u015faret\u00e7inin K\u00f6keni ve \u0130lk S\u00f6z\u00fc<\/h2>\n<p>Sarkan i\u015faret\u00e7iler kavram\u0131, 1970&#039;lerde d\u00fc\u015f\u00fck seviyeli programlama dillerinin geli\u015ftirilmesiyle ortaya \u00e7\u0131kt\u0131. Yayg\u0131n olarak kullan\u0131lan bir programlama dili olan C, i\u015faret\u00e7iler arac\u0131l\u0131\u011f\u0131yla belle\u011fin do\u011frudan manip\u00fclasyonuna izin verdi; bu esneklik sa\u011flad\u0131 ancak ayn\u0131 zamanda sarkan i\u015faret\u00e7iler olu\u015fturma olas\u0131l\u0131\u011f\u0131n\u0131 da ortaya \u00e7\u0131kard\u0131. &quot;Sarkan i\u015faret\u00e7i&quot; terimi muhtemelen C programlaman\u0131n ilk g\u00fcnlerinde, programc\u0131lar\u0131n belle\u011fi manuel olarak y\u00f6netmekle u\u011fra\u015ft\u0131\u011f\u0131 d\u00f6nemde ortaya at\u0131lm\u0131\u015ft\u0131.<\/p>\n<h2>Sarkan \u0130\u015faret\u00e7i Hakk\u0131nda Detayl\u0131 Bilgi: Konuyu Geni\u015fletmek<\/h2>\n<p>Bellek serbest b\u0131rak\u0131ld\u0131\u011f\u0131nda veya serbest b\u0131rak\u0131ld\u0131\u011f\u0131nda sarkan i\u015faret\u00e7iler olu\u015fur, ancak bir i\u015faret\u00e7i yine de belle\u011fin eskiden oldu\u011fu konuma ba\u015fvurur. Bu \u015fu durumlarda ger\u00e7ekle\u015febilir:<\/p>\n<ol>\n<li>\n<p>Bellek, a\u015fa\u011f\u0131daki i\u015flevler kullan\u0131larak a\u00e7\u0131k\u00e7a serbest b\u0131rak\u0131l\u0131r: <code data-no-translation=\"\">free()<\/code> C veya <code data-no-translation=\"\">delete<\/code> C++&#039;da. \u0130\u015faret\u00e7i sallan\u0131r hale gelir ve de\u011ferine eri\u015fmeye y\u00f6nelik sonraki giri\u015fimler tan\u0131ms\u0131z davran\u0131\u015fa yol a\u00e7ar.<\/p>\n<\/li>\n<li>\n<p>Bir i\u015faret\u00e7i bildirildi\u011finde ba\u015flat\u0131lmaz veya NULL&#039;a ayarlanmaz ve iste\u011fe ba\u011fl\u0131 bellek konumlar\u0131na i\u015faret edebilir. D\u00fczg\u00fcn atanmazsa, kullan\u0131ld\u0131\u011f\u0131nda sarkan bir i\u015faret\u00e7iye d\u00f6n\u00fc\u015febilir.<\/p>\n<\/li>\n<li>\n<p>Bir i\u015faret\u00e7i, i\u015flev geri d\u00f6n\u00fc\u015flerinde oldu\u011fu gibi kapsam d\u0131\u015f\u0131na \u00e7\u0131kar ve i\u015faret\u00e7iyi art\u0131k ge\u00e7ersiz olan bir bellek konumuna i\u015faret eder halde b\u0131rak\u0131r.<\/p>\n<\/li>\n<\/ol>\n<h2>Sarkan \u0130\u015faret\u00e7inin \u0130\u00e7 Yap\u0131s\u0131: Nas\u0131l \u00c7al\u0131\u015f\u0131r?<\/h2>\n<p>Bir program bir i\u015faret\u00e7i olu\u015fturdu\u011funda ve belle\u011fi dinamik olarak ay\u0131rd\u0131\u011f\u0131nda (\u00f6rn. <code data-no-translation=\"\">malloc()<\/code> veya <code data-no-translation=\"\">new<\/code>), bu haf\u0131zan\u0131n izini s\u00fcrmek ve art\u0131k ihtiya\u00e7 duyulmad\u0131\u011f\u0131nda onu uygun \u015fekilde serbest b\u0131rakmak \u00e7ok \u00f6nemlidir. Bellek serbest b\u0131rak\u0131ld\u0131ktan sonra bir i\u015faret\u00e7i g\u00fcncellenmezse veya NULL olarak ayarlanmazsa, daha \u00f6nce ayr\u0131lm\u0131\u015f belle\u011fin adresini saklamaya devam edecek ve sarkan bir i\u015faret\u00e7i haline gelecektir. Daha sonra, sarkan i\u015faret\u00e7inin referans\u0131n\u0131n kald\u0131r\u0131lmas\u0131 veri bozulmas\u0131na, program \u00e7\u00f6kmelerine veya g\u00fcvenlik a\u00e7\u0131klar\u0131na yol a\u00e7abilir.<\/p>\n<h2>Sarkan \u0130\u015faret\u00e7inin Temel \u00d6zelliklerinin Analizi<\/h2>\n<p>Sarkan i\u015faret\u00e7ilerin temel \u00f6zellikleri \u015funlard\u0131r:<\/p>\n<ol>\n<li>\n<p><strong>Tan\u0131ms\u0131z Davran\u0131\u015f<\/strong>: Bir program, sarkan bir i\u015faret\u00e7i arac\u0131l\u0131\u011f\u0131yla verilere eri\u015fmeye \u00e7al\u0131\u015ft\u0131\u011f\u0131nda, davran\u0131\u015f tan\u0131ms\u0131zd\u0131r ve \u00f6ng\u00f6r\u00fclemeyen sonu\u00e7lara yol a\u00e7abilir.<\/p>\n<\/li>\n<li>\n<p><strong>Tespit edilmesi zor<\/strong>: Sarkan i\u015faret\u00e7ileri belirlemek, \u00f6zellikle b\u00fcy\u00fck kod tabanlar\u0131nda zor olabilir. Etkileri hemen ortaya \u00e7\u0131kmayabilir, bu da hata ay\u0131klamay\u0131 sorunlu hale getirebilir.<\/p>\n<\/li>\n<li>\n<p><strong>G\u00fcvenlik riskleri<\/strong>: Sarkan i\u015faret\u00e7ilerden yararlanmak, serbest kullan\u0131m sonras\u0131 g\u00fcvenlik a\u00e7\u0131klar\u0131 gibi belirli g\u00fcvenlik sald\u0131r\u0131s\u0131 t\u00fcrlerinde yayg\u0131n bir tekniktir.<\/p>\n<\/li>\n<\/ol>\n<h2>Sarkan \u0130\u015faret\u00e7i T\u00fcrleri<\/h2>\n<p>Sarkan i\u015faret\u00e7iler, nedenlerine g\u00f6re farkl\u0131 t\u00fcrlerde s\u0131n\u0131fland\u0131r\u0131labilir:<\/p>\n<table>\n<thead>\n<tr>\n<th>Tip<\/th>\n<th>Tan\u0131m<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Bo\u015f Sarkan \u0130\u015faret\u00e7i<\/td>\n<td>NULL&#039;a i\u015faret eden veya ba\u015flat\u0131lmam\u0131\u015f bir i\u015faret\u00e7i.<\/td>\n<\/tr>\n<tr>\n<td>Y\u0131\u011f\u0131n Sarkan \u0130\u015faret\u00e7i<\/td>\n<td>Bir i\u015flev geri d\u00f6nd\u00fckten sonra sarkan i\u015faret\u00e7iler.<\/td>\n<\/tr>\n<tr>\n<td>Y\u0131\u011f\u0131n Sarkan \u0130\u015faret\u00e7i<\/td>\n<td>Ayr\u0131lmam\u0131\u015f belle\u011fe ba\u015fvuran i\u015faret\u00e7iler.<\/td>\n<\/tr>\n<tr>\n<td>Vah\u015fi \u0130\u015faret\u00e7iler<\/td>\n<td>Ba\u015flat\u0131lmam\u0131\u015f ve rastgele adresler i\u00e7eren i\u015faret\u00e7iler.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Sarkan \u0130\u015faret\u00e7iyi Kullanma Yollar\u0131, Sorunlar ve \u00c7\u00f6z\u00fcmleri<\/h2>\n<p>Sarkan i\u015faret\u00e7iler olu\u015fturmaktan ka\u00e7\u0131nmak genellikle en iyisi olsa da bazen belirli programlama tekniklerinde kas\u0131tl\u0131 olarak kullan\u0131labilirler. Ancak bu, altta yatan haf\u0131za y\u00f6netiminin derinlemesine anla\u015f\u0131lmas\u0131n\u0131 gerektirir ve potansiyel riskleri de beraberinde getirir. Sarkan i\u015faret\u00e7ilerle ilgili yayg\u0131n sorunlar \u015funlard\u0131r:<\/p>\n<ol>\n<li>\n<p><strong>Bellek Bozulmas\u0131<\/strong>: Sarkan i\u015faret\u00e7iler belle\u011fi bozabilir, bu da program karars\u0131zl\u0131\u011f\u0131na veya \u00e7\u00f6kmelere neden olabilir.<\/p>\n<\/li>\n<li>\n<p><strong>G\u00fcvenlik A\u00e7\u0131klar\u0131<\/strong>: Sarkan i\u015faret\u00e7ilerden yararlanmak, sald\u0131rganlar\u0131n hassas verilere yetkisiz eri\u015fim sa\u011flamak veya k\u00f6t\u00fc ama\u00e7l\u0131 kod y\u00fcr\u00fctmek i\u00e7in yayg\u0131n bir taktiktir.<\/p>\n<\/li>\n<li>\n<p><strong>Bellek S\u0131z\u0131nt\u0131lar\u0131<\/strong>: Sarkan i\u015faret\u00e7ilerin yanl\u0131\u015f i\u015flenmesi, ayr\u0131lan belle\u011fin hi\u00e7bir zaman serbest b\u0131rak\u0131lmad\u0131\u011f\u0131 bellek s\u0131z\u0131nt\u0131lar\u0131na yol a\u00e7arak program\u0131n bellek ayak izinin zamanla b\u00fcy\u00fcmesine neden olabilir.<\/p>\n<\/li>\n<\/ol>\n<p>Sarkan i\u015faret\u00e7ileri y\u00f6netmeye y\u00f6nelik \u00e7\u00f6z\u00fcmler \u015funlar\u0131 i\u00e7erir:<\/p>\n<ul>\n<li>Sarkan i\u015faret\u00e7ilere d\u00f6n\u00fc\u015fmelerini \u00f6nlemek i\u00e7in i\u015faret\u00e7ileri belle\u011fi serbest b\u0131rakt\u0131ktan sonra daima NULL&#039;a ayarlay\u0131n.<\/li>\n<li>Kapsam d\u0131\u015f\u0131na \u00e7\u0131kan ve ge\u00e7ersiz hale gelen i\u015faret\u00e7ileri kullanmaktan ka\u00e7\u0131n\u0131n.<\/li>\n<li>Belle\u011fin serbest b\u0131rak\u0131lmas\u0131n\u0131n daha sa\u011flam \u015fekilde y\u00f6netilmesine yard\u0131mc\u0131 olan ak\u0131ll\u0131 i\u015faret\u00e7ileri veya bellek y\u00f6netimi kitapl\u0131klar\u0131n\u0131 kullan\u0131n.<\/li>\n<\/ul>\n<h2>Ana \u00d6zellikler ve Benzer Terimlerle Kar\u015f\u0131la\u015ft\u0131rmalar<\/h2>\n<table>\n<thead>\n<tr>\n<th>Terim<\/th>\n<th>Tan\u0131m<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Sarkan \u0130\u015faret\u00e7i<\/td>\n<td>Ayr\u0131lm\u0131\u015f belle\u011fe i\u015faret eden bir i\u015faret\u00e7i.<\/td>\n<\/tr>\n<tr>\n<td>Bo\u015f i\u015faret\u00e7isi<\/td>\n<td>Herhangi bir bellek konumuna i\u015faret etmeyen bir i\u015faret\u00e7i.<\/td>\n<\/tr>\n<tr>\n<td>Vah\u015fi \u0130\u015faret\u00e7i<\/td>\n<td>Rastgele bir adres i\u00e7eren ve ba\u015flat\u0131lmam\u0131\u015f bir i\u015faret\u00e7i.<\/td>\n<\/tr>\n<tr>\n<td>Ge\u00e7ersiz \u0130\u015faret\u00e7i<\/td>\n<td>T\u00fcr bilgisi bulunmayan genel bir i\u015faret\u00e7i t\u00fcr\u00fc.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Sarkan i\u015faret\u00e7iler, davran\u0131\u015flar\u0131 ve program \u00fczerindeki olas\u0131 etkileri a\u00e7\u0131s\u0131ndan bo\u015f i\u015faret\u00e7ilerden, vah\u015fi i\u015faret\u00e7ilerden ve ge\u00e7ersiz i\u015faret\u00e7ilerden farkl\u0131d\u0131r. Bo\u015f i\u015faret\u00e7iler ve ge\u00e7ersiz i\u015faret\u00e7iler do\u011fas\u0131 gere\u011fi sorunlu olmasa da, \u00e7\u0131lg\u0131n i\u015faret\u00e7iler ve sarkan i\u015faret\u00e7iler yanl\u0131\u015f kullan\u0131ld\u0131\u011f\u0131nda ciddi sorunlara yol a\u00e7abilir.<\/p>\n<h2>Sarkan \u0130\u015faret\u00e7iye \u0130li\u015fkin Perspektifler ve Gelecek Teknolojiler<\/h2>\n<p>Modern programlama dillerinde i\u015faret\u00e7ilerin y\u00f6netimi ve bellek tahsisi \u00f6nemli \u00f6l\u00e7\u00fcde geli\u015fmi\u015ftir. Java, C# ve Python gibi daha yeni diller, otomatik bellek y\u00f6netimi (\u00e7\u00f6p toplama) veya daha g\u00fcvenli i\u015faret\u00e7i i\u015fleme mekanizmalar\u0131 kullanarak sarkan i\u015faret\u00e7iler olu\u015fturma riskini azalt\u0131r.<\/p>\n<p>Ancak performans a\u00e7\u0131s\u0131ndan kritik uygulamalarda ve sistem programlamada C ve C++ hala yayg\u0131n olarak kullan\u0131lmaktad\u0131r. Ara\u015ft\u0131rmac\u0131lar ve dil geli\u015ftiricileri, belle\u011fi daha verimli bir \u015fekilde y\u00f6netmek ve i\u015faret\u00e7ilerin sarkmas\u0131 gibi sorunlar\u0131 \u00f6nlemek i\u00e7in \u00e7\u00f6z\u00fcmler ke\u015ffetmeye devam ediyor.<\/p>\n<h2>Proxy Sunucular\u0131 Nas\u0131l Kullan\u0131labilir veya Sarkan \u0130\u015faret\u00e7iyle Nas\u0131l \u0130li\u015fkilendirilebilir?<\/h2>\n<p>Proxy sunucular\u0131, istemciler ve sunucular aras\u0131nda arac\u0131 g\u00f6revi g\u00f6rerek \u00f6nbelle\u011fe alma, i\u00e7erik filtreleme ve g\u00fcvenlik geli\u015ftirmeleri gibi \u00e7e\u015fitli i\u015flevler sa\u011flar. Proxy sunucular\u0131 sarkan i\u015faret\u00e7ilerle do\u011frudan ili\u015fkili olmasa da, web uygulamas\u0131 g\u00fcvenli\u011finde \u00e7ok \u00f6nemli bir rol oynarlar. Proxy sunucular\u0131, sarkan i\u015faret\u00e7ilerden ve bellekle ilgili di\u011fer sorunlardan kaynaklananlar da dahil olmak \u00fczere yayg\u0131n g\u00fcvenlik a\u00e7\u0131klar\u0131na kar\u015f\u0131 koruma sa\u011flayan g\u00fcvenlik \u00f6nlemlerini uygulamak i\u00e7in kullan\u0131labilir.<\/p>\n<h2>\u0130lgili Ba\u011flant\u0131lar<\/h2>\n<p>Sarkan \u0130\u015faret\u00e7iler hakk\u0131nda daha fazla bilgi i\u00e7in a\u015fa\u011f\u0131daki kaynaklara ba\u015fvurabilirsiniz:<\/p>\n<ol>\n<li><a href=\"https:\/\/en.cppreference.com\/w\/c\/memory\/dangling\" target=\"_new\" rel=\"noopener nofollow\">C++ Referans\u0131: Sarkan \u0130\u015faret\u00e7iler<\/a><\/li>\n<li><a href=\"https:\/\/www.geeksforgeeks.org\/understanding-extern-keyword-in-c\/\" target=\"_new\" rel=\"noopener nofollow\">C&#039;de Bellek Y\u00f6netimini ve \u0130\u015faret\u00e7ileri Anlamak<\/a><\/li>\n<li><a href=\"https:\/\/www.cprogramming.com\/tutorial\/c\/lesson10.html\" target=\"_new\" rel=\"noopener nofollow\">Yayg\u0131n C Programlama Hatalar\u0131<\/a><\/li>\n<\/ol>\n<p>Sarkan i\u015faret\u00e7ileri anlaman\u0131n ve y\u00f6netmenin, sa\u011flam ve g\u00fcvenli yaz\u0131l\u0131m yazmak i\u00e7in \u00e7ok \u00f6nemli oldu\u011funu unutmay\u0131n. Geli\u015ftiriciler, bellek tahsisini ve serbest b\u0131rakmay\u0131 dikkatli bir \u015fekilde ele alarak, sarkan i\u015faret\u00e7ilerle ili\u015fkili bir\u00e7ok potansiyel tuza\u011f\u0131 \u00f6nleyebilir.<\/p>","protected":false},"featured_media":476586,"menu_order":0,"template":"","meta":{"_acf_changed":false,"content-type":"","inline_featured_image":false,"footnotes":""},"class_list":["post-476585","wiki","type-wiki","status-publish","has-post-thumbnail","hentry"],"acf":{"faq_title":"Frequently Asked Questions about <mark>Dangling Pointer: Understanding the Potential Pitfalls<\/mark>","faq_items":[{"question":"What is a dangling pointer?","answer":"<p>A dangling pointer is a pointer in computer programming that points to a memory location that has been deallocated or freed. When a program attempts to access the memory at that location, it can lead to unexpected and potentially hazardous behavior.<\/p>"},{"question":"How did the concept of dangling pointers originate?","answer":"<p>The concept of dangling pointers emerged with the development of low-level programming languages in the 1970s, particularly in languages like C and C++. The term \"dangling pointer\" was likely coined during the early days of C programming when programmers faced challenges managing memory manually.<\/p>"},{"question":"How does a dangling pointer work internally?","answer":"<p>When memory is deallocated or freed, a pointer that still references the deallocated memory becomes a dangling pointer. If the program attempts to access the memory through the dangling pointer, it can result in undefined behavior, causing data corruption, program crashes, or security vulnerabilities.<\/p>"},{"question":"What are the key features of dangling pointers?","answer":"<p>Key features of dangling pointers include:<\/p><ul><li><strong>Undefined Behavior<\/strong>: Accessing data through a dangling pointer leads to unpredictable outcomes.<\/li><li><strong>Difficult to Detect<\/strong>: Identifying dangling pointers in large codebases can be challenging, making debugging problematic.<\/li><li><strong>Security Risks<\/strong>: Dangling pointers can be exploited in security attacks, such as use-after-free vulnerabilities.<\/li><\/ul>"},{"question":"What types of dangling pointers exist?","answer":"<p>Dangling pointers can be classified into different types based on their causes:<\/p><ul><li><strong>Null Dangling Pointer<\/strong>: A pointer that points to NULL or has not been initialized.<\/li><li><strong>Stack Dangling Pointer<\/strong>: Pointers that become dangling after a function returns.<\/li><li><strong>Heap Dangling Pointer<\/strong>: Pointers that reference deallocated memory.<\/li><li><strong>Wild Pointers<\/strong>: Pointers that have not been initialized and contain arbitrary addresses.<\/li><\/ul>"},{"question":"Can dangling pointers be used intentionally?","answer":"<p>In some specific programming techniques, dangling pointers might be used intentionally. However, it requires a deep understanding of memory management and entails potential risks. Generally, it is best to avoid creating dangling pointers to ensure program stability and security.<\/p>"},{"question":"What problems can be associated with dangling pointers?","answer":"<p>Problems related to dangling pointers include:<\/p><ul><li><strong>Memory Corruption<\/strong>: Dangling pointers can corrupt memory and cause program instability or crashes.<\/li><li><strong>Security Vulnerabilities<\/strong>: Exploiting dangling pointers is a common tactic for attackers to gain unauthorized access to sensitive data or execute malicious code.<\/li><li><strong>Memory Leaks<\/strong>: Mishandling dangling pointers can result in memory leaks, causing the program's memory footprint to grow over time.<\/li><\/ul>"},{"question":"How can developers manage dangling pointers?","answer":"<p>To manage dangling pointers effectively, developers should:<\/p><ul><li>Always set pointers to NULL after deallocating memory to prevent them from becoming dangling pointers.<\/li><li>Avoid using pointers that go out of scope and become invalid.<\/li><li>Use smart pointers or memory management libraries that help in handling memory deallocation more robustly.<\/li><\/ul>"},{"question":"How do proxy servers relate to dangling pointers?","answer":"<p>Proxy servers play a crucial role in web application security. While they are not directly associated with dangling pointers, they can be used to implement security measures that protect against common vulnerabilities, including those arising from memory-related issues.<\/p>"},{"question":"Are there any future technologies related to dangling pointers?","answer":"<p>In modern programming languages, memory management has evolved significantly, with newer languages using automatic memory management or safer pointer handling mechanisms. Researchers and language developers continue to explore solutions to manage memory more efficiently and prevent issues like dangling pointers.<\/p>"}]},"_links":{"self":[{"href":"https:\/\/oneproxy.pro\/tr\/wp-json\/wp\/v2\/wiki\/476585","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/oneproxy.pro\/tr\/wp-json\/wp\/v2\/wiki"}],"about":[{"href":"https:\/\/oneproxy.pro\/tr\/wp-json\/wp\/v2\/types\/wiki"}],"version-history":[{"count":0,"href":"https:\/\/oneproxy.pro\/tr\/wp-json\/wp\/v2\/wiki\/476585\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/oneproxy.pro\/tr\/wp-json\/wp\/v2\/media\/476586"}],"wp:attachment":[{"href":"https:\/\/oneproxy.pro\/tr\/wp-json\/wp\/v2\/media?parent=476585"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}