From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9430231ED68; Fri, 17 Apr 2026 07:33:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.25 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776411184; cv=none; b=JNo+d3WWVVA1QIHwpMTeVNIVHYzn5KtQ3awC0/ycr6/gkqPOs3/V5JeZv47YTg14cOA3eNTJsPhrqEWwg0vy88Lo810GqE5Wj79LwKgomyi4mLH9FkzOslvvK/zXhnFx4zEI+DY5oBct46gm1AJ2eOWpaN0InIZfV2g7zjNuwNc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776411184; c=relaxed/simple; bh=slhT4iyxtRhdMnv0PzjaVTEaKAozy1qiIHZ5NKnGwtg=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=amovWeKLewoqP7U8xMg4sZm7d7ZWsuURt4ABjsXqwajmis3dk48mgON3k1J/arH9v8wPjvUdgfFbDw9CUNRRfEGMSLTBn0A6DSlE1FbUgJR/8PxRq4AMJiYZLYLDhQ8nV1fJIcCJQxBmFqw+1AUoj6Vhq0x+v2sB9YcHy90ARLI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from localhost.localdomain (unknown [111.196.245.116]) by APP-05 (Coremail) with SMTP id zQCowACXKQ0i4uFpvNXXDQ--.61497S2; Fri, 17 Apr 2026 15:32:50 +0800 (CST) From: Pengpeng Hou To: Kentaro Takeda , Tetsuo Handa Cc: Paul Moore , James Morris , "Serge E. Hallyn" , linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, Pengpeng Hou , stable@vger.kernel.org Subject: [PATCH] tomoyo: reject short exec.envp[] names before suffix checks Date: Fri, 17 Apr 2026 15:32:49 +0800 Message-ID: <20260417073249.93906-1-pengpeng@iscas.ac.cn> X-Mailer: git-send-email 2.50.1 Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:zQCowACXKQ0i4uFpvNXXDQ--.61497S2 X-Coremail-Antispam: 1UD129KBjvJXoWxJr45Kr4DAF4rGrW8Zry7KFg_yoW8JFW8pr 4akFy2grn5JFWSyw4xtw18CFyrCan5Cr43Ga9xAFySy3W3XF1Iq3WjgF4rur1rCr4xtrW2 vw4jvry3KFWDJFJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUkK14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26F1j6w1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_Jrv_JF1lYx0Ex4A2jsIE14v26r4j6F4UMcvjeVCFs4IE7xkEbVWUJV W8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1lc7CjxVAaw2AFwI0_ Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67 AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIY rxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14 v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVW8JVWx JwCI42IY6I8E87Iv6xkF7I0E14v26r4UJVWxJrUvcSsGvfC2KfnxnUUI43ZEXa7VUbzpBD UUUUU== X-CM-SenderInfo: pshqw1xhqjqxpvfd2hldfou0/ tomoyo_parse_envp() assumes that the left-hand side still ends with the closing '"' and ']' from an exec.envp["..."] condition and immediately backs up from strlen(left) - 1 to verify that suffix. If policy input leaves an empty or one-byte string here, the parser reads before the start of the token while checking for the suffix. Reject left-hand strings that are too short to contain the required '"]' terminator before dereferencing the trailing characters. Fixes: 5b636857fee6 ("TOMOYO: Allow using argv[]/envp[] of execve() as conditions.") Cc: stable@vger.kernel.org Signed-off-by: Pengpeng Hou --- security/tomoyo/condition.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/security/tomoyo/condition.c b/security/tomoyo/condition.c index f8bcc083bb0d..1fa8343df4b3 100644 --- a/security/tomoyo/condition.c +++ b/security/tomoyo/condition.c @@ -320,7 +320,13 @@ static bool tomoyo_parse_envp(char *left, char *right, { const struct tomoyo_path_info *name; const struct tomoyo_path_info *value; - char *cp = left + strlen(left) - 1; + size_t len = strlen(left); + char *cp; + + if (len < 2) + goto out; + + cp = left + len - 1; if (*cp-- != ']' || *cp != '"') goto out; -- 2.50.1 (Apple Git-155)