In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
dm: avoid leaking the caller’s thread keyring via the table device file<\/p>\n
The refactoring in commit a28d893eb327 (“md: port block device access to file”)
\naccidentally causes the caller’s thread keyring to be kept alive long
\nbeyond the caller’s lifetime.<\/p>\n
As a result, “cryptsetup luksSuspend” silently fails to wipe the
\nLUKS volume key from memory.<\/p>\n
In detail: “cryptsetup luksOpen” uses its supposedly ephemeral thread
\nkeyring to pass the volume key to the kernel. dm-crypt’s
\ncrypt_set_keyring_key() copies the key material into its own
\ncrypt_config structure and then drops its own reference to the key in
\nthe keyring with key_put().<\/p>\n
With this fix, restoring pre-v6.9 behavior, the copy in the thread
\nkeyring is then promptly garbage collected, such that exactly one copy
\nof the volume key remains. This single copy is correctly wiped from
\nmemory on “cryptsetup luksSuspend”.<\/p>\n
Without this fix, the thread keyring and the volume key in it remains.
\nThis second copy is only freed on “luksClose”. “luksSuspend” neither
\nknows about this copy nor has any way to remove it, so the key remains
\nrecoverable from RAM after a suspend that is documented to have wiped it.<\/p>\n
This fix should not introduce new security problems, as the code is
\nanyway gated by CAP_SYS_ADMIN. The device-mapper core, not the calling
\ntask, is the legitimate owner of this long-lived file.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
dm: avoid leaking the caller’s thread keyring via the table device file<\/p>\n
The refactoring in commit a28d893eb327 (“md: port block de<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-6773","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/6773","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=6773"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6773"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6773"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}