{"id":21693,"date":"2026-09-12T04:31:32","date_gmt":"2026-09-11T20:31:32","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-89771"},"modified":"2026-09-12T04:31:32","modified_gmt":"2026-09-11T20:31:32","slug":"cve-2026-89771","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-89771","title":{"rendered":"CVE-2026-89771 &#8211; In the Linux kernel, the following vulnerability has been resolved:\n\nring-buffer: Fix subb"},"content":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>ring-buffer: Fix subbuf resize race with ring buffer readers<\/p>\n<p>trace_buffer subbuf_size is read lockless in ring_buffer_read_page() and<br \/>\nring_buffer_read_start(), while it can simultaneously be resized with<br \/>\nring_buffer_subbuf_order_set().<\/p>\n<p>Instead of trace_buffer::subbuf_size, use bpage::order in<br \/>\nring_buffer_read_start() and ring_buffer_read_page().<\/p>\n<p>In ring_buffer_read_start(), even with resize_disabled, there is still a<br \/>\npossibility of a race with a buffer modification. Hold the trace_buffer<br \/>\nmutex to synchronise with any pending ring buffer order modification.<\/p>\n<p>trace_buffer::subbuf_size is now actually useless, remove it. Also,<br \/>\ncreate accessors rb_subbuf_capacity() and rb_page_capacity() which<br \/>\nreturn the actual size available for storing events, while<br \/>\nrb_subbuf_size() returns the actual subbuf page-size.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>ring-buffer: Fix subbuf resize race with ring buffer readers<\/p>\n<p>trace_buffer subbuf_size is read lockless in ring_buffer_read_page() <\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-21693","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/21693","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=21693"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21693"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21693"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}