{"id":26024,"date":"2026-09-18T04:32:14","date_gmt":"2026-09-17T20:32:14","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-93167"},"modified":"2026-09-18T04:32:14","modified_gmt":"2026-09-17T20:32:14","slug":"cve-2026-93167","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-93167","title":{"rendered":"CVE-2026-93167 &#8211; In the Linux kernel, the following vulnerability has been resolved:\n\ncsky: Fix a4\/a5 resto"},"content":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>csky: Fix a4\/a5 restoration in syscall trace path<\/p>\n<p>The syscall trace path reloads syscall arguments from pt_regs before<br \/>\ncalling the syscall handler. On C-SKY ABIv2, the 5th and 6th syscall<br \/>\narguments are prepared as stack arguments before invoking syscallid.<\/p>\n<p>The current code adjusts sp before loading LSAVE_A4 and LSAVE_A5. Since<br \/>\nthose offsets are relative to the original pt_regs base, loading them<br \/>\nafter changing sp fetches the wrong slots. As a result, traced syscalls<br \/>\nthat use the 5th or 6th argument may receive corrupted arguments.<\/p>\n<p>This is visible with mmap2(), which takes six arguments. A small<br \/>\nPTRACE_SYSCALL reproducer opens a file and maps one page with:<\/p>\n<p>  mmap(NULL, 4096, PROT_READ | PROT_EXEC, MAP_PRIVATE, fd, 0)<\/p>\n<p>Before the fix, the traced child fails the mmap and exits with 12.<br \/>\nAfter the fix, the mapping succeeds and the child exits with 0.<\/p>\n<p>Fix the trace path by loading a4\/a5 from pt_regs before changing sp.<\/p>\n<p>Tested on: ck860f, linux-4.19.15, C-SKY abiv2<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>csky: Fix a4\/a5 restoration in syscall trace path<\/p>\n<p>The syscall trace path reloads syscall arguments from pt_regs before<br \/>\ncalling the<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-26024","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/26024","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=26024"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=26024"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=26024"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}