Ua ʻike ʻo Tavis Ormandy, kahi mea noiʻi palekana ma Google, i kahi vulnerability hou (CVE-2023-23583) i nā kaʻina Intel, codenamed Reptar, ka mea nui e hoʻoweliweli i nā ʻōnaehana kapua e holo ana i nā mīkini virtual o nā mea hoʻohana like ʻole. ʻO ka nāwaliwali e hiki ai i ka ʻōnaehana ke kau a hāʻule paha i ka wā e hana ʻia ai kekahi mau hana ma nā ʻōnaehana malihini pono ʻole. No ka hoʻāʻo ʻana i kāu mau ʻōnaehana, ua paʻi ʻia kahi mea pono e hana i nā kūlana no ka hōʻike ʻana i nā nāwaliwali.
ʻO ka manaʻo, hiki ke hoʻohana ʻia ka nāwaliwali e hoʻonui i nā pono mai ke kolu a hiki i ke apo palekana zero (CPL0) a pakele mai nā wahi kaʻawale, akā ʻaʻole i hōʻoia ʻia kēia hiʻohiʻona ma ka hoʻomaʻamaʻa ma muli o nā pilikia o ka debugging ma ka pae microarchitectural. Ua hōʻike pū kekahi loiloi kūloko ma Intel i ka hiki ke hoʻohana i ka nāwaliwali e hoʻonui i nā pono ma lalo o kekahi mau kūlana.
Wahi a ka mea noiʻi, aia ka nāwaliwali ma ka Intel Ice Lake, Rocket Lake, Tiger Lake, Raptor Lake, Alder Lake a me nā ʻohana processor Sapphire Rapids. Hōʻike ka Intel hōʻike e ʻike ʻia ka pilikia e hoʻomaka ana mai ka hanauna 10th (Ice Lake) o nā kaʻina Intel Core a me ke kolu o ka hanauna o Xeon Scalable processors, a me Xeon E / D / W processors (Ice Lake, Skylake, Haswell, Broadwell. , Skylake, Sapphire Rapids, Emerald Rapids, Cascade Lake, Cooper Lake, Comet Lake, Rocket Lake) a me Atom (Apollo Lake, Jasper Lake, Arizona Beach, Alder Lake, Parker Ridge, Snow Ridge, Elkhart Lake a me Denverton). Ua hoʻopaʻa ʻia ka nāwaliwali i nīnau ʻia ma ka microcode update 20231114 i nehinei.
Hoʻokumu ʻia ka nāwaliwali ma ka ʻoiaʻiʻo ma lalo o kekahi mau kūlana microarchitectural, ua hoʻopili ʻia ka hoʻokō ʻana o ke aʻo "REP MOVSB" me kahi prefix "REX" kiʻekiʻe, e alakaʻi ana i kahi ʻano ʻike ʻole. Ua ʻike ʻia ka pilikia i ka wā o ka hoʻāʻo ʻana i nā prefix redundant, a ma ke kumumanaʻo e mālama ʻole ʻia, akā ma ka hoʻomaʻamaʻa ua alakaʻi i nā hopena ʻē aʻe, e like me ka nānā ʻole ʻana i nā lālā kīnā ʻole a me ka haki ʻana i ka pointer e mālama i ka xsave a kāhea i nā ʻōlelo aʻoaʻo. Ua hōʻike hou ʻia ka nānā ʻana i ka hoʻohui ʻana i kahi prefix redundant i ke aʻo ʻana "REP MOVSB" e hoʻopōʻino i nā ʻike o ka pahu ROB (ReOrder Buffer) i hoʻohana ʻia e kauoha i nā kuhikuhi.
Manaʻo ʻia ʻo ka hewa ke kumu o ka helu hewa ʻana o ka nui o ke aʻo "MOVSB", e alakaʻi ana i ka uhaki ʻana i ka ʻōlelo ʻana i nā ʻōlelo aʻoaʻo i kākau ʻia i ka buffer ROB ma hope o ka MOVSB me kahi prefix nui, a me ka offset. o ke kuhikuhi kuhikuhi. Hiki ke kaupalena ʻia ia desynchronization i ka hoʻopau ʻana i nā helu waena me ka hoʻihoʻi hou ʻana o ka mokuʻāina hoʻohui. Akā inā e hoʻopololei ʻoe i nā cores a i ʻole nā kaula SMT i ka manawa like, hiki iā ʻoe ke hōʻino i ka mokuʻāina microarchitectural e hiki ke hāʻule.
Source: opennet.ru
