Cov kws tshawb fawb ntawm ETH Zurich tau tsim ZenHammer nres, qhov sib txawv ntawm RowHammer chav kawm ntawm kev tawm tsam los hloov kho cov ntsiab lus ntawm ib tus neeg ntawm cov khoom siv dynamic random nkag tau lub cim xeeb (DRAM), yoog rau siv hauv platforms nrog AMD processors. Yav dhau los RowHammer txoj kev tawm tsam tau txwv rau cov kab ke raws li Intel processors, tab sis kev tshawb fawb tau pom tias kev ua txhaum cai nco kuj tuaj yeem ua tiav ntawm cov platforms nrog AMD nco controllers.
Cov txheej txheem tau pom ntawm AMD Zen 2 thiab Zen 3 systems nrog DDR4 nco los ntawm peb lub tuam txhab ua lag luam (Samsung, Micron thiab SK Hynix). Qhov kev tawm tsam tau ua tiav dhau los ntawm TRR (Target Row Refresh) cov txheej txheem siv hauv cov cim xeeb chips, uas yog tsom rau kev tiv thaiv kev noj nyiaj txiag ntawm lub cim xeeb ntawm cov kab uas nyob ib sab. Raws li cov kws tshawb fawb, cov txheej txheem raws li AMD Zen 3 CPUs muaj kev cuam tshuam ntau dua li cov txheej txheem nrog Intel Coffee Lake processors, thiab lawv yooj yim dua thiab zoo dua los tua. Ntawm AMD Zen 2 systems, cell distortion tau ua tiav rau 7 tawm ntawm 10 kuaj DDR4 chips, thiab ntawm Zen 3 systems rau 6 tawm ntawm 10. Cov kws tshawb fawb kuj tau txheeb xyuas qhov muaj peev xwm ntawm kev tawm tsam ntawm AMD Zen 4 systems nrog DDR5 nco, tab sis kev tawm tsam. txoj kev tsim rau DDR4 tau ua tiav rov ua tiav ntawm tsuas yog 1 ntawm 10 tau sim DDR5 lub cim xeeb chips, thaum muaj peev xwm ntawm kev tawm tsam nws tus kheej tsis suav nrog, tab sis yuav tsum muaj kev txhim kho cov qauv nyeem ntawv zoo dua rau DDR5 li.
Txhawm rau ua haujlwm nrog AMD chips, lawv tuaj yeem hloov kho yav dhau los tsim kev siv dag zog uas hloov cov ntsiab lus nkag hauv nplooj ntawv nco (PTE, nplooj ntawv nkag) kom tau txais cov cai tshwj xeeb, hla lo lus zais / tso cai kuaj xyuas los ntawm kev hloov kho lub cim xeeb ntawm cov txheej txheem sudo , thiab ua rau RSA-2048 pej xeem tus yuam sij khaws cia hauv lub cim xeeb hauv OpenSSH kom rov tsim dua tus yuam sij ntiag tug. Cov nplooj ntawv nco tau rov ua dua tshiab ntawm 7 ntawm 10 DDR4 chips tau sim, RSA tseem ceeb nres ntawm 6 chips, thiab sudo nres ntawm 4 chips, nrog lub sijhawm nres ntawm 164, 267, thiab 209 vib nas this, raws li.
Txoj kev no kuj tseem siv tau los tawm tsam lub system los ntawm cov browsers kom hloov pauv los ntawm cov tshuab virtual los yog npaj ib qho kev tawm tsam hauv network. Cov lej qhov chaw rau DARE toolkit rau kev tsim kho dua tshiab DRAM chaw nyob layouts muaj nyob rau ntawm GitHub nyob rau hauv daim ntawv tso cai MIT, nrog rau ob pawg ntawm cov khoom siv rau kev puas tsuaj ntawm lub cim xeeb me me—ddr4_zen2_zen3_pub rau DDR4 chips (Zen 2 thiab Zen 3) thiab ddr5_zen4_pub rau DDR5 chips (Zen 4). Cov no tuaj yeem siv los sim koj cov kab ke rau qhov tsis muaj zog ntawm kev tawm tsam.
Txoj kev RowHammer yog siv los cuam tshuam cov khoom, uas yog raws li qhov tseeb tias hauv DRAM nco, uas yog ob-dimensional array ntawm cov hlwb uas muaj lub capacitor thiab transistor, ua qhov kev nyeem tas mus li ntawm tib lub cim xeeb cheeb tsam ua rau muaj kev hloov pauv voltage thiab anomalies uas ua rau ib tug me me poob ntawm nqi nyob ze cov hlwb. Yog tias qhov kev nyeem ntawv siv siab heev, ces cov xov tooj ntawm tes uas nyob sib ze yuav poob tus nqi txaus txaus thiab lub voj voog rov ua dua tshiab yuav tsis muaj sijhawm los rov qab los ntawm nws lub xeev qub, uas yuav ua rau muaj kev hloov pauv ntawm tus nqi ntawm cov ntaub ntawv khaws cia hauv cell. . Tus kws tshawb fawb tau txheeb xyuas cov yam ntxwv ntawm lub cev nco daim ntawv qhia thiab synchronization nrog lub cim xeeb hloov kho cov cuab yeej siv hauv AMD processors, uas ua rau nws muaj peev xwm rov tsim dua DRAM theem qis, txiav txim siab qhov chaw nyob ntawm cov hlwb nyob sib ze, tsim txoj hauv kev los hla caching, thiab suav cov qauv thiab zaus. ntawm kev ua haujlwm uas ua rau poob nqi.
Txhawm rau tiv thaiv RowHammer, cov tuam txhab chip siv TRR (Target Row Refresh) mechanism, uas thaiv cov xov tooj ntawm tes tsis zoo hauv cov xwm txheej tshwj xeeb, tab sis tsis tiv thaiv txhua txoj kev tawm tsam. Txoj kev tiv thaiv zoo tshaj plaws tseem yog kev siv lub cim xeeb nrog cov lej kho qhov yuam kev (ECC), uas cuam tshuam loj heev, tab sis tsis tshem tawm tag nrho, RowHammer tawm tsam. Kev nce qhov zaus ntawm kev rov tsim dua lub cim xeeb kuj tuaj yeem txo qhov tshwm sim ntawm kev ua tiav zoo.
AMD tau tshaj tawm tsab ntawv tshaj tawm txog qhov teeb meem hais tias AMD processors siv lub cim xeeb tswj uas ua raws li DDR cov lus qhia, thiab txij li qhov kev ua tiav ntawm kev tawm tsam yog nyob ntawm qhov kev teeb tsa thiab DRAM nco, cov lus nug txog kev daws qhov teeb meem yuav tsum tau hais rau lub cim xeeb manufacturers. thiab systems Muaj txoj hauv kev los ua kom Rowhammer-chav tawm tsam nyuaj ntxiv suav nrog kev siv ECC lub cim xeeb, nce qhov zaus ntawm lub cim xeeb rov tsim dua tshiab, cuam tshuam rau kev ncua sijhawm rov tsim dua tshiab, thiab siv cov txheej txheem nrog cov tswj hwm uas txhawb nqa MAC (Qhov Tshaj Tawm Tshaj Tshaj Tshaj Tshaj Tshaj Tshaj) rau DDR4 (1st, 2nd thiab 3rd. tiam AMD EPYC "Naple", "Rome" thiab "Milan") thiab RFM (Refresh Management) rau DDR5 (4th tiam AMD EPYC).
Tau qhov twg los: opennet.ru
