In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
arm64\/boot: Disable trapping of PMZR_EL0 writes to EL2<\/p>\n
__init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2.
\nPMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in
\nHDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host
\ntraps to EL2, where the nVHE hypervisor has no handler and BUG()s. The
\nkernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU
\ndriver set PMUSERENR_EL0.UEN for a task with a user-read event, so a
\nwrite from EL0 reaches the trap and takes the host down without a panic
\nmessage.<\/p>\n
Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already
\ndoes for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9
\nbits.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
arm64\/boot: Disable trapping of PMZR_EL0 writes to EL2<\/p>\n
__init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2.
\nPM<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-41018","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/41018","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=41018"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=41018"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=41018"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}