From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ED2DA8F57 for ; Sun, 16 Jul 2023 20:44:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F963C433C7; Sun, 16 Jul 2023 20:44:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1689540265; bh=wjKjA0s3XKSSNvU7qudBTzAy7cty+bh63U8zU/vCBE0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0kSyHWhlqdpZZmKJbOcN7F2Sn300+btEJ+46P5clkFobOsD6r091ugvLVLICVVnrK hfEgJ05A4Hmbubz1cbureOlXzAzja/QPvhsM4OkHtxvs4ruLbCxSzCLiqkITbXcb6p SOGyQjT0pXwKK/nZqdUsuuq3H+1Jg2jtPy4QTtho= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mark Pearson , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Hans de Goede , Sasha Levin Subject: [PATCH 6.1 301/591] platform/x86: think-lmi: mutex protection around multiple WMI calls Date: Sun, 16 Jul 2023 21:47:20 +0200 Message-ID: <20230716194931.682607459@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230716194923.861634455@linuxfoundation.org> References: <20230716194923.861634455@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Mark Pearson [ Upstream commit c41e0121a1221894a1a9c4666156db9e1def4d6c ] When an attribute is being changed if the Admin account is enabled, or if a password is being updated then multiple WMI calls are needed. Add mutex protection to ensure no race conditions are introduced. Fixes: b49f72e7f96d ("platform/x86: think-lmi: Certificate authentication support") Signed-off-by: Mark Pearson Reviewed-by: Ilpo Järvinen Reviewed-by: Hans de Goede Link: https://lore.kernel.org/r/20230601200552.4396-1-mpearson-lenovo@squebb.ca Signed-off-by: Hans de Goede Signed-off-by: Sasha Levin --- drivers/platform/x86/think-lmi.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/platform/x86/think-lmi.c b/drivers/platform/x86/think-lmi.c index 336b9029d1515..4e6040c0a2201 100644 --- a/drivers/platform/x86/think-lmi.c +++ b/drivers/platform/x86/think-lmi.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -195,6 +196,7 @@ static const char * const level_options[] = { }; static struct think_lmi tlmi_priv; static struct class *fw_attr_class; +static DEFINE_MUTEX(tlmi_mutex); /* ------ Utility functions ------------*/ /* Strip out CR if one is present */ @@ -437,6 +439,9 @@ static ssize_t new_password_store(struct kobject *kobj, /* Strip out CR if one is present, setting password won't work if it is present */ strip_cr(new_pwd); + /* Use lock in case multiple WMI operations needed */ + mutex_lock(&tlmi_mutex); + pwdlen = strlen(new_pwd); /* pwdlen == 0 is allowed to clear the password */ if (pwdlen && ((pwdlen < setting->minlen) || (pwdlen > setting->maxlen))) { @@ -493,6 +498,7 @@ static ssize_t new_password_store(struct kobject *kobj, kfree(auth_str); } out: + mutex_unlock(&tlmi_mutex); kfree(new_pwd); return ret ?: count; } @@ -982,6 +988,9 @@ static ssize_t current_value_store(struct kobject *kobj, /* Strip out CR if one is present */ strip_cr(new_setting); + /* Use lock in case multiple WMI operations needed */ + mutex_lock(&tlmi_mutex); + /* Check if certificate authentication is enabled and active */ if (tlmi_priv.certificate_support && tlmi_priv.pwd_admin->cert_installed) { if (!tlmi_priv.pwd_admin->signature || !tlmi_priv.pwd_admin->save_signature) { @@ -1040,6 +1049,7 @@ static ssize_t current_value_store(struct kobject *kobj, kobject_uevent(&tlmi_priv.class_dev->kobj, KOBJ_CHANGE); } out: + mutex_unlock(&tlmi_mutex); kfree(auth_str); kfree(set_str); kfree(new_setting); -- 2.39.2