In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
nvdimm\/btt: Handle preemption in BTT lane acquisition<\/p>\n
BTT lanes serialize access to per-lane metadata and workspace state
\nduring BTT I\/O. The btt-check unit test reports data mismatches during
\nBTT writes due to a race in lane acquisition that can lead to silent
\ndata corruption.<\/p>\n
The existing lane model uses a spinlock together with a per-CPU
\nrecursion count. That recursion model stopped being valid after BTT
\nlanes became preemptible: another task can run on the same CPU,
\nobserve a non-zero recursion count, bypass locking, and use the same
\nlane concurrently.<\/p>\n
BTT lanes are also held across arena_write_bytes() calls. That path
\nreaches nsio_rw_bytes(), which flushes writes with nvdimm_flush().
\nSome provider flush callbacks can sleep, making a spinlock the wrong
\nprimitive for the lane lifetime.<\/p>\n
Replace the spinlock-based recursion model with a dynamically
\nallocated per-lane mutex array and take the lane lock
\nunconditionally.<\/p>\n
Add might_sleep() to catch any future atomic-context caller.<\/p>\n
Found with the ndctl unit test btt-check.sh.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
nvdimm\/btt: Handle preemption in BTT lane acquisition<\/p>\n
BTT lanes serialize access to per-lane metadata and workspace state
\nduring B<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-7318","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/7318","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=7318"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7318"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7318"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}