In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
arm64: hibernate: mask DAIF before restoring hibernated kernel<\/p>\n
The arm64 hibernate code manages the exception masking in an unsound
\nway, leading to potential crashes and\/or warnings during resume.<\/p>\n
When a hibernation image is saved in `swsusp_arch_suspend()`, all DAIF
\nexceptions are masked (by virtue of `local_daif_save()`), and the
\nsuspended image is saved assuming that all DAIF exceptions will remain
\nmasked when the image is restored.<\/p>\n
When a hibernation image is resumed by `swsusp_arch_resume()`, only
\ninterrupts are masked (by virtue of `local_irq_disable()` in
\n`resume_target_kernel()`). When pseudo-NMI is enabled the DAIF.IF bits
\nwill be clear, and regardless of pseudo-NMI the DAIF.DA bits will be
\nclear.<\/p>\n
This means that there are two problems:<\/p>\n
(1) It is possible to take Debug, SError, or pseudo-NMI exceptions
\n during the resume process. This is unsafe, as during the resume
\n process both the old ane new kernels will tranisently be in an
\n inconsistent state, and swsusp_arch_suspend_exit() won’t retain
\n an executable mapping of any exception vectors.<\/p>\n
Any exception taken here will be fatal and silent.<\/p>\n
(2) When re-entering the resumed kernel, some DAIF bits will be clear
\n unexpectedly. This permits Debug, SError, or pseudo-NMI exceptions
\n to be taken for a short period while the resumed kernel is not yet
\n in a consistent state.<\/p>\n
This is detected by CONFIG_ARM64_DEBUG_PRIORITY_MASKING.<\/p>\n
Avoid these issues by masking all DAIF exceptions during resume.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
arm64: hibernate: mask DAIF before restoring hibernated kernel<\/p>\n
The arm64 hibernate code manages the exception masking in an unsoun<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-28520","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/28520","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=28520"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=28520"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=28520"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}