{"id":25460,"date":"2026-09-18T04:31:24","date_gmt":"2026-09-17T20:31:24","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-90051"},"modified":"2026-09-18T04:31:24","modified_gmt":"2026-09-17T20:31:24","slug":"cve-2026-90051","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-90051","title":{"rendered":"CVE-2026-90051 &#8211; In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: reject non zeroc"},"content":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>tcp: reject non zerocopy devmem tx<\/p>\n<p>Devmem tcp tx doesn&#8217;t work without zero-copy, however it&#8217;s not currently<br \/>\nenforced if NETIF_F_SG isn&#8217;t present. In this case, tcp_sendmsg_locked()<br \/>\nwill try the copy path and try to copy data from an iovec which consists<br \/>\nof offsets into the dma-buf and would normally fail. Moreover,<br \/>\nd9c56501c72fd (&#8220;net: tcp: block mixing readable and unreadable frags&#8221;)<br \/>\nrelies on that and assumes that the devmem binding is present IFF we&#8217;re<br \/>\nusing the zero-copy path, which can be used to mix net-iov and pages in<br \/>\na single skb, and break invariants. Let&#8217;s reject devmem tx without<br \/>\nzero-copy.<\/p>\n<p>Note, the parameter check the patch is modifying is too loose, we can<br \/>\ncreate an io_uring request with dmabuf_id and all ZC flags, but which<br \/>\nwon&#8217;t have the binding. We replace it with stricter validation.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>tcp: reject non zerocopy devmem tx<\/p>\n<p>Devmem tcp tx doesn&#8217;t work without zero-copy, however it&#8217;s not currently<br \/>\nenforced if NETIF_F_SG<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-25460","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/25460","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=25460"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=25460"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=25460"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}