{"cve":"CVE-2025-22035","nvd":{"published":"2025-04-16T15:15:56.110","modified":"2026-06-17T08:44:53.903","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Fix use-after-free in print_graph_function_flags during tracer switching\n\nKairui reported a UAF issue in print_graph_function_flags() during\nftrace stress testing [1]. This issue can be reproduced if puting a\n'mdelay(10)' after 'mutex_unlock(&trace_types_lock)' in s_start(),\nand executing the following script:\n\n  $ echo function_graph > current_tracer\n  $ cat trace > /dev/null &\n  $ sleep 5  # Ensure the 'cat' reaches the 'mdelay(10)' point\n  $ echo timerlat > current_tracer\n\nThe root cause lies in the two calls to print_graph_function_flags\nwithin print_trace_line during each s_show():\n\n  * One through 'iter->trace->print_line()';\n  * Another through 'event->funcs->trace()', which is hidden in\n    print_trace_fmt() before print_trace_line returns.\n\nTracer switching only updates the former, while the latter continues\nto use the print_line function of the old tracer, which in the script\nabove is print_graph_function_flags.\n\nMoreover, when switching from the 'function_graph' tracer to the\n'timerlat' tracer, s_start only calls graph_trace_close of the\n'function_graph' tracer to free 'iter->private', but does not set\nit to NULL. This provides an opportunity for 'event->funcs->trace()'\nto use an invalid 'iter->private'.\n\nTo fix this issue, set 'iter->private' to NULL immediately after\nfreeing it in graph_trace_close(), ensuring that an invalid pointer\nis not passed to other tracers. Additionally, clean up the unnecessary\n'iter->private = NULL' during each 'cat trace' when using wakeup and\nirqsoff tracers.\n\n [1] https://lore.kernel.org/all/20231112150030.84609-1-ryncsn@gmail.com/","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/099ef3385800828b74933a96c117574637c3fb3a","https://git.kernel.org/stable/c/42561fe62c3628ea3bc9623f64f047605e98857f","https://git.kernel.org/stable/c/70be951bc01e4a0e10d443f3510bb17426f257fb","https://git.kernel.org/stable/c/7f81f27b1093e4895e87b74143c59c055c3b1906","https://git.kernel.org/stable/c/81a85b12132c8ffe98f5ddbdc185481790aeaa1b"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:01:11.054312287+00:00"},"epss":{"cve":"CVE-2025-22035","score":0.003,"percentile":0.22787,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}