{"id":106545,"date":"2023-01-29T12:48:46","date_gmt":"2023-01-29T10:48:46","guid":{"rendered":"https:\/\/prohoster.info\/?p=106545"},"modified":"2023-02-07T12:09:03","modified_gmt":"2023-02-07T10:09:03","slug":"zavisimost-vremeni-vypolneniya-instrukczij-ot-dannyh-na-cpu-arm-i-intel","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/news\/zavisimost-vremeni-vypolneniya-instrukczij-ot-dannyh-na-cpu-arm-i-intel","title":{"rendered":"Z\u00e1vislost doby vykon\u00e1v\u00e1n\u00ed instrukc\u00ed na datech na CPU ARM a Intel","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Eric Biggers, jeden z v\u00fdvoj\u00e1\u0159\u016f \u0161ifry Adiantum a maintainer subsyst\u00e9mu j\u00e1dra Linux fscrypt, navrhl sadu patch\u016f, kter\u00e9 \u0159e\u0161\u00ed bezpe\u010dnostn\u00ed probl\u00e9my vypl\u00fdvaj\u00edc\u00ed z charakteristiky procesor\u016f Intel, kter\u00e1 negarantuje konstantn\u00ed \u010das prov\u00e1d\u011bn\u00ed instrukc\u00ed pro r\u016fzn\u00e1 zpracov\u00e1van\u00e1 data. U procesor\u016f Intel se tento probl\u00e9m projevuje od rodiny Ice Lake. Podobn\u00fd probl\u00e9m je tak\u00e9 p\u0159\u00edtomen u procesor\u016f ARM. <\/p>\n

Z\u00e1vislost \u010dasu prov\u00e1d\u011bn\u00ed instrukc\u00ed na datech zpracov\u00e1van\u00fdch v t\u011bchto instrukc\u00edch je autorem patch\u016f pova\u017eov\u00e1na za zranitelnost v procesorech, proto\u017ee takov\u00e9 chov\u00e1n\u00ed nem\u016f\u017ee zaru\u010dit bezpe\u010dnost kryptografick\u00fdch operac\u00ed prov\u00e1d\u011bn\u00fdch v syst\u00e9mu. Mnoho implementac\u00ed kryptografick\u00fdch algoritm\u016f p\u0159edpokl\u00e1d\u00e1, \u017ee data nemaj\u00ed vliv na \u010das prov\u00e1d\u011bn\u00ed instrukc\u00ed, a toto poru\u0161en\u00ed chov\u00e1n\u00ed m\u016f\u017ee v\u00e9st k \u00fatok\u016fm pomoc\u00ed bo\u010dn\u00edch kan\u00e1l\u016f, kter\u00e9 obnovuj\u00ed data na z\u00e1klad\u011b anal\u00fdzy \u010dasu jejich zpracov\u00e1n\u00ed. <\/p>\n

Potenci\u00e1ln\u011b m\u016f\u017ee b\u00fdt z\u00e1vislost \u010dasu prov\u00e1d\u011bn\u00ed na datech tak\u00e9 pou\u017eita pro organizaci \u00fatok\u016f k ur\u010den\u00ed dat j\u00e1dra z u\u017eivatelsk\u00e9ho prostoru. Podle Erika Biggersa nen\u00ed konstantn\u00ed \u010das prov\u00e1d\u011bn\u00ed zaru\u010den ani pro instrukce prov\u00e1d\u011bj\u00edc\u00ed operace s\u010d\u00edt\u00e1n\u00ed a XOR, ani pro specializovan\u00e9 instrukce AES-NI (informace nebyly potvrzeny testy, podle jin\u00fdch \u00fadaj\u016f p\u0159i n\u00e1soben\u00ed vektor\u016f a po\u010d\u00edt\u00e1n\u00ed bit\u016f vznik\u00e1 zpo\u017ed\u011bn\u00ed o jeden cyklus). <\/p>\n

Pro deaktivaci zkouman\u00e9ho chov\u00e1n\u00ed companies Intel a ARM navrhly nov\u00e9 flagy: PSTATE-bit DIT (Data Independent Timing) pro CPU ARM a MSR-bit DOITM (Data Operand Independent Timing Mode) pro CPU Intel, kter\u00e9 vrac\u00ed star\u00e9 chov\u00e1n\u00ed s konstantn\u00edm \u010dasem prov\u00e1d\u011bn\u00ed. Spole\u010dnosti Intel a ARM doporu\u010duj\u00ed aktivovat ochranu podle pot\u0159eby pro obzvl\u00e1\u0161\u0165 d\u016fle\u017eit\u00fd k\u00f3d, ale ve skute\u010dnosti se d\u016fle\u017eit\u00e9 v\u00fdpo\u010dty mohou vyskytovat v jak\u00fdchkoli \u010d\u00e1stech j\u00e1dra a u\u017eivatelsk\u00e9ho prostoru, a proto se zva\u017euje mo\u017enost trval\u00e9 aktivace re\u017eim\u016f DOITM a DIT pro cel\u00e9 j\u00e1dro. <\/p>\n

Pro procesory ARM byly do j\u00e1dra Linux 6.2 ji\u017e p\u0159ijaty opravy, kter\u00e9 m\u011bn\u00ed chov\u00e1n\u00ed j\u00e1dra, av\u0161ak tyto opravy jsou pova\u017eov\u00e1ny za nedostate\u010dn\u00e9, proto\u017ee pokr\u00fdvaj\u00ed pouze k\u00f3d j\u00e1dra a nem\u011bn\u00ed chov\u00e1n\u00ed v u\u017eivatelsk\u00e9m prostoru. Pro procesory Intel je zapnut\u00ed ochrany zat\u00edm jen ve f\u00e1zi revize. M\u011b\u0159en\u00ed vlivu opravy na v\u00fdkon zat\u00edm nebylo provedeno, ale podle dokumentace Intel zapnut\u00ed re\u017eimu DOITM sni\u017euje v\u00fdkon (nap\u0159\u00edklad kv\u016fli vypnut\u00ed n\u011bkter\u00fdch optimalizac\u00ed, jako je p\u0159edb\u011b\u017en\u00e9 na\u010d\u00edt\u00e1n\u00ed specifick\u00e9 pro ur\u010dit\u00e9 \u00fadaje) a v budouc\u00edch modelech procesor\u016f m\u016f\u017ee sn\u00ed\u017een\u00ed v\u00fdkonu zes\u00edlit.
\n
Zdroj: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u042d\u0440\u0438\u043a \u0411\u0438\u0433\u0433\u0435\u0440\u0441 (Eric Biggers), \u043e\u0434\u0438\u043d \u0438\u0437 \u0440\u0430\u0437\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a\u043e\u0432 \u0448\u0438\u0444\u0440\u0430 Adiantum \u0438 \u043c\u044d\u0439\u043d\u0442\u0435\u0439\u043d\u0435\u0440 \u043f\u043e\u0434\u0441\u0438\u0441\u0442\u0435\u043c\u044b \u044f\u0434\u0440\u0430 Linux fscrypt, \u043f\u0440\u0435\u0434\u043b\u043e\u0436\u0438\u043b \u043d\u0430\u0431\u043e\u0440 \u043f\u0430\u0442\u0447\u0435\u0439 \u0434\u043b\u044f \u0431\u043b\u043e\u043a\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f \u043f\u0440\u043e\u0431\u043b\u0435\u043c \u0441 \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u044c\u044e, \u0432\u043e\u0437\u043d\u0438\u043a\u0430\u044e\u0449\u0438\u0445 \u0438\u0437-\u0437\u0430 \u043e\u0441\u043e\u0431\u0435\u043d\u043d\u043e\u0441\u0442\u0438 \u043f\u0440\u043e\u0446\u0435\u0441\u0441\u043e\u0440\u043e\u0432 Intel, \u043d\u0435 \u0433\u0430\u0440\u0430\u043d\u0442\u0438\u0440\u0443\u044e\u0449\u0435\u0439 \u043f\u043e\u0441\u0442\u043e\u044f\u043d\u043d\u043e\u0435 \u0432\u0440\u0435\u043c\u044f \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u044f \u0438\u043d\u0441\u0442\u0440\u0443\u043a\u0446\u0438\u0439 \u0434\u043b\u044f \u0440\u0430\u0437\u043d\u044b\u0445 \u043e\u0431\u0440\u0430\u0431\u0430\u0442\u044b\u0432\u0430\u0435\u043c\u044b\u0445 \u0434\u0430\u043d\u043d\u044b\u0445. \u0412 \u043f\u0440\u043e\u0446\u0435\u0441\u0441\u043e\u0440\u0430\u0445 Intel \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u043f\u0440\u043e\u044f\u0432\u043b\u044f\u0435\u0442\u0441\u044f \u043d\u0430\u0447\u0438\u043d\u0430\u044f \u0441 \u0441\u0435\u043c\u0435\u0439\u0441\u0442\u0432\u0430 Ice Lake. \u0410\u043d\u0430\u043b\u043e\u0433\u0438\u0447\u043d\u0430\u044f \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u043d\u0430\u0431\u043b\u044e\u0434\u0430\u0435\u0442\u0441\u044f \u0438 \u0432 \u043f\u0440\u043e\u0446\u0435\u0441\u0441\u043e\u0440\u0430\u0445 ARM. […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[702],"tags":[],"class_list":["post-106545","post","type-post","status-publish","format-standard","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\n","aioseo_head_json":{"title":"\ud83e\udd47Z\u00e1vislost doby prov\u00e1d\u011bn\u00ed instrukc\u00ed na datech na CPU ARM a Intel | ProHoster","description":"Eric Biggers, jeden z v\u00fdvoj\u00e1\u0159\u016f \u0161ifry Adiantum a spr\u00e1vce pod syst\u00e9mu j\u00e1dra Linux fscrypt, navrhl sadu opravy pro zablokov\u00e1n\u00ed bezpe\u010dnostn\u00edch probl\u00e9m\u016f, kter\u00e9 vznikaj\u00ed kv\u016fli specifick\u00fdm vlastnostem procesor\u016f.","canonical_url":"https:\/\/prohoster.info\/cs\/blog\/news\/zavisimost-vremeni-vypolneniya-instrukczij-ot-dannyh-na-cpu-arm-i-intel","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"cs_CZ","og:site_name":"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b","og:type":"article","og:title":"\ud83e\udd47\u0417\u0430\u0432\u0438\u0441\u0438\u043c\u043e\u0441\u0442\u044c \u0432\u0440\u0435\u043c\u0435\u043d\u0438 \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u044f \u0438\u043d\u0441\u0442\u0440\u0443\u043a\u0446\u0438\u0439 \u043e\u0442 \u0434\u0430\u043d\u043d\u044b\u0445 \u043d\u0430 CPU ARM \u0438 Intel | ProHoster","og:description":"\u042d\u0440\u0438\u043a \u0411\u0438\u0433\u0433\u0435\u0440\u0441 (Eric Biggers), \u043e\u0434\u0438\u043d \u0438\u0437 \u0440\u0430\u0437\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a\u043e\u0432 \u0448\u0438\u0444\u0440\u0430 Adiantum \u0438 \u043c\u044d\u0439\u043d\u0442\u0435\u0439\u043d\u0435\u0440 \u043f\u043e\u0434\u0441\u0438\u0441\u0442\u0435\u043c\u044b \u044f\u0434\u0440\u0430 Linux fscrypt, \u043f\u0440\u0435\u0434\u043b\u043e\u0436\u0438\u043b \u043d\u0430\u0431\u043e\u0440 \u043f\u0430\u0442\u0447\u0435\u0439 \u0434\u043b\u044f \u0431\u043b\u043e\u043a\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f \u043f\u0440\u043e\u0431\u043b\u0435\u043c \u0441 \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u044c\u044e, \u0432\u043e\u0437\u043d\u0438\u043a\u0430\u044e\u0449\u0438\u0445 \u0438\u0437-\u0437\u0430 \u043e\u0441\u043e\u0431\u0435\u043d\u043d\u043e\u0441\u0442\u0438 \u043f\u0440\u043e\u0446\u0435\u0441\u0441\u043e\u0440\u043e\u0432.","og:url":"https:\/\/prohoster.info\/cs\/blog\/news\/zavisimost-vremeni-vypolneniya-instrukczij-ot-dannyh-na-cpu-arm-i-intel","og:image":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:secure_url":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:width":350,"og:image:height":350,"article:published_time":"2023-01-29T10:48:46+00:00","article:modified_time":"2023-02-07T10:09:03+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":[],"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/106545","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/comments?post=106545"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/posts\/106545\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/media?parent=106545"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/categories?post=106545"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/cs\/wp-json\/wp\/v2\/tags?post=106545"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}