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Wysocki" , Viresh Kumar Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, Justin Stitt Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (lipwig.vger.email [0.0.0.0]); Tue, 12 Sep 2023 17:08:00 -0700 (PDT) X-Spam-Status: No, score=-8.4 required=5.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lipwig.vger.email X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1776910504398396926 X-GMAIL-MSGID: 1776910504398396926 `strncpy` is deprecated for use on NUL-terminated destination strings [1]. We should prefer more robust and less ambiguous string interfaces. Both `policy->last_governor` and `default_governor` are expected to be NUL-terminated which is shown by their heavy usage with other string apis like `strcmp`. A suitable replacement is `strscpy` [2] due to the fact that it guarantees NUL-termination on the destination buffer. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2] Link: https://github.com/KSPP/linux/issues/90 Cc: linux-hardening@vger.kernel.org Signed-off-by: Justin Stitt Reviewed-by: Kees Cook Acked-by: Viresh Kumar --- Note: build-tested --- drivers/cpufreq/cpufreq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- base-commit: 2dde18cd1d8fac735875f2e4987f11817cc0bc2c change-id: 20230912-strncpy-drivers-cpufreq-cpufreq-c-1d800044b007 Best regards, -- Justin Stitt diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 50bbc969ffe5..3eb851a03fce 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1607,7 +1607,7 @@ static void __cpufreq_offline(unsigned int cpu, struct cpufreq_policy *policy) } if (has_target()) - strncpy(policy->last_governor, policy->governor->name, + strscpy(policy->last_governor, policy->governor->name, CPUFREQ_NAME_LEN); else policy->last_policy = policy->policy; @@ -2951,7 +2951,7 @@ static int __init cpufreq_core_init(void) BUG_ON(!cpufreq_global_kobject); if (!strlen(default_governor)) - strncpy(default_governor, gov->name, CPUFREQ_NAME_LEN); + strscpy(default_governor, gov->name, CPUFREQ_NAME_LEN); return 0; }