In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
ethtool: cmis: require exact CDB reply length<\/p>\n
Malicious SFP module could respond with rpl_len longer than
\nwhat cmis_cdb_process_reply() expected, leading to OOB writes.
\nMalicious HW is a bit theoretical but some modules may just
\nbe buggy and\/or the reads may occasionally get corrupted,
\nso let’s protect the kernel.<\/p>\n
The existing check protects from short replies. We need to
\nprotect from long ones, too. All callers that pass a non-zero
\nrpl_exp_len cast the reply payload to a fixed-layout struct
\nand read fields at fixed offsets, with no version negotiation
\nor short-reply handling:<\/p>\n
– cmis_cdb_validate_password()
\n – cmis_cdb_module_features_get()
\n – cmis_fw_update_fw_mng_features_get()<\/p>\n
so let’s assume that responses longer than expected do not
\nhave to be handled gracefully here. Add a warning message
\nto make the debug easier in case my understanding is wrong…<\/p>\n
Note that page_data->length (argument of kmalloc) comes from
\nlast arg to ethtool_cmis_page_init() which is rpl_exp_len.<\/p>\n
Note2 that AIs also like to point out overflows in args->req.payload
\nitself (which is a fixed-size 120 B buffer, on the stack),
\nbut callers should be reading structs defined by the standard,
\nso protecting from requests for more data than max seem like
\ndefensive programming.<\/p>\n","protected":false},"excerpt":{"rendered":"
In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
ethtool: cmis: require exact CDB reply length<\/p>\n
Malicious SFP module could respond with rpl_len longer than
\nwhat cmis_cdb_process_re<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-15000","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/15000","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=15000"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=15000"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=15000"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}