{"id":"CVE-2026-90002","summary":"ftrace: Take trace_array reference before accessing its ftrace_ops","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nftrace: Take trace_array reference before accessing its ftrace_ops\n\nThe trace instance files set_ftrace_filter and set_ftrace_notrace was\nupdated to work with specific trace instances (trace_arrays). The issue is\nthat when these files are opened, there is a small race window where it\nwill use the ftrace_ops from the inode-\u003eprivate pointer to get a reference\nto the trace_array and then take its reference. The problem is that the\nftrace_ops itself could be freed. If the rmdir on the instance happens at\nthe same time the set_ftrace_filter file is opened, the rmdir could have\nalso freed the ftrace_ops and referencing it will cause a use-after-free\nbug and crash the kernel.\n\nInstead, pass in the trace_array as the file private data (NULL for the\ntop level instance), and then pass both the trace_array and the ftrace_ops\nto the ftrace_regex_open() function. If the trace_array is NULL, then it\njust uses the ftrace_ops without the need to take its reference (like\nnormal). If the ftrace_ops is NULL, that is only the case for the top\nlevel instance and the global_ops can be used.\n\nThis allows the trace_array to have its reference incremented before\ntouching the ftrace_ops that could also be freed when the instance is.","modified":"2026-09-17T03:47:23.582737545Z","published":"2026-09-16T10:33:12.734Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90002.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/83fd7eca5ab0d3ac3f23bff889175d847e21af06"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9100191e5acb2e5ea2313f436667bb5fce129f47"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cee8f286794df916553d8d445eac5c323ec5b0f8"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90002.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90002"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"591dffdade9f07692a7dd3ed16830ec24e901ece"},{"fixed":"83fd7eca5ab0d3ac3f23bff889175d847e21af06"},{"fixed":"cee8f286794df916553d8d445eac5c323ec5b0f8"},{"fixed":"9100191e5acb2e5ea2313f436667bb5fce129f47"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90002.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.15.0"},{"fixed":"6.18.52"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90002.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}