In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
sched_ext: Don’t run ops.dequeue() with a DSQ lock held<\/p>\n
ops.dequeue() is invoked with the source user DSQ’s lock still held on
\nthe consume and move paths (scx_consume_dispatch_q(),
\nmove_task_between_dsqs()). A BPF scheduler which locks the source user
\nDSQ from ops.dequeue() – e.g. by iterating it with bpf_iter_scx_dsq –
\nself-deadlocks.<\/p>\n
ops.dequeue() can only call the “any” kfuncs and none of them can lock a
\nbuiltin DSQ, so the global and bypass paths can’t deadlock; however,
\nall DSQ locks share one lockdep class, so iterating any user DSQ from
\nops.dequeue() on those paths trips the recursion check.<\/p>\n
Move the invocation after the DSQ unlock on all three paths.
\nSCX_TASK_IN_CUSTODY is cleared under the lock serializing the transfer
\nso that the callback is invoked exactly once.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
sched_ext: Don’t run ops.dequeue() with a DSQ lock held<\/p>\n
ops.dequeue() is invoked with the source user DSQ’s lock still held on
\nthe<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-41337","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/41337","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=41337"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=41337"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=41337"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}