In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
KVM: arm64: vgic-v3: take an LPI reference in vgic_v3_save_pending_tables<\/p>\n
vgic_v3_save_pending_tables() iterates dist->lpi_xa using xa_for_each()
\nand dereferences the returned struct vgic_irq in the loop body without
\nholding a reference on the LPI.<\/p>\n
The xarray iterator only provides temporary RCU coverage while looking up
\nthe current entry. That is not sufficient for this loop body, which reads
\nfields from struct vgic_irq and performs guest memory accesses before the
\niteration completes.<\/p>\n
A concurrent path can trigger this race: the irqfd cached injection path
\n(vgic_its_inject_cached_translation) obtains a transient LPI reference
\nvia vgic_its_check_cache() without holding kvm->lock, vcpu->mutex,
\nconfig_lock, or its_lock. If guest ITS DISCARD then drops the cache and
\nITE references under its_lock, the transient inject reference may become
\nthe final one. When vgic_put_irq() drops it, the LPI is erased from
\nlpi_xa and freed via kfree_rcu(). Meanwhile, vgic_v3_save_pending_tables()
\nmay still hold a stale pointer obtained from the xarray iterator and
\ndereference it after the RCU grace period completes.<\/p>\n
Fix this by re-fetching each iterated LPI via vgic_get_irq(), which takes
\na stable reference, and dropping it with vgic_put_irq() on all paths.
\nThis matches the pattern already used by other lpi_xa iterators in the
\nvgic ITS code.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
KVM: arm64: vgic-v3: take an LPI reference in vgic_v3_save_pending_tables<\/p>\n
vgic_v3_save_pending_tables() iterates dist->lpi_xa usin<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-24600","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/24600","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=24600"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=24600"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=24600"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}