In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
bpf: Mark NULL kptr stores precise<\/p>\n
check_map_kptr_access() permits a scalar store into an untrusted kptr
\nfield only when the register is known to contain zero. Unlike other
\nverifier checks whose outcome depends on a scalar value, it does not mark
\nthat register precise.<\/p>\n
A state checkpoint reached with an imprecise zero can therefore prune a
\nsecond path that reaches the store with an arbitrary nonzero scalar. The
\nprogram can write attacker-controlled bits into the kptr field and load
\nthem back as a PTR_TO_BTF_ID.<\/p>\n
Call mark_chain_precision() before accepting a known-zero register. This
\nforces state equivalence to compare its scalar range and makes the verifier
\nvisit and reject a path carrying a nonzero value.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
bpf: Mark NULL kptr stores precise<\/p>\n
check_map_kptr_access() permits a scalar store into an untrusted kptr
\nfield only when the regis<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-29189","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/29189","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=29189"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=29189"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=29189"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}