Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 55061377A89; Thu, 20 Aug 2026 16:27:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787243264; cv=none; b=NOy6d2GLm+Tf2sgiNhIm0g1FFwnN8KS33AzHQ7tj0A/B4Bb1U5+ek9s/rADhvyX9mn5NGIucI79JXsbbj/sT8dwllQv3gI2ZIzE9Skz0Kc72I6axLhjl6dhXvkflnbYhjD856hcHm1+FNnlk7o70yIIZlx3Dih3XHqFImcf0XAg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787243264; c=relaxed/simple; bh=d/pLfFcmeJfVCa6CLuqYn/+rypobZpErR/jXPANiPpU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Vu6oauv8wWbXsBSDNgUQo22WslCirweD6vLfVad+b/Olzxgtg8mONpHMGUxrhSc0Mwz6dQyM66qZsKxvLerP+vOQKpsKCMVgcmJAUUIkVtwloihPpMEsQgxDltYkts9hvZaLKB6vcHUIM643tV7QL6suLeTDYvbc4x1/0z1Jjys= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=tJQF0EpU; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="tJQF0EpU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AF2131F000E9; Thu, 20 Aug 2026 16:27:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787243263; bh=R/4ndjqkYZKQxMxR3ET0Ra14f1VHq6AjKyeCq4EsdTU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=tJQF0EpUUuO+Xqaho/0Kxt9d2bjf/r3v4NlutVH010G2c9+PC7+iEk1hRuLYQW9Au C4FP6/2eqz6+dPJWqLgXNkhF+4cmUz8Pl79v5NZuBC0Hjm+axJuw2uzz6Xtva3RStw wvOQYV3HADQIq6RiPCaZVVyCDgtYKabHe4IwwStk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Bryam Vargas , Stephen Smalley , Paul Moore Subject: [PATCH 5.15 007/272] selinux: reject a class permission count below its inherited common Date: Thu, 20 Aug 2026 16:53:11 +0200 Message-ID: <20260820145231.456046027@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260820145231.229664293@linuxfoundation.org> References: <20260820145231.229664293@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bryam Vargas commit 9a82dcd98b6e6e11cfd162410967951f12152528 upstream. security_get_permissions() maps an inherited common's permissions into an array sized by the class's own permissions.nprim, but class_read() takes that nprim verbatim from the policy image and never checks that it covers the common. A class that inherits a common of N permissions while declaring a smaller nprim is accepted, and on load the common's permissions are written past the class-sized array -- an out-of-bounds heap write. Reject a class whose permission count is below its inherited common's. Well-formed policies, where the class count already includes the inherited permissions, are unaffected. Cc: stable@vger.kernel.org Fixes: 55fcf09b3fe4 ("selinux: add support for querying object classes and permissions from the running policy") Signed-off-by: Bryam Vargas Acked-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Greg Kroah-Hartman --- security/selinux/ss/policydb.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/security/selinux/ss/policydb.c +++ b/security/selinux/ss/policydb.c @@ -1356,6 +1356,18 @@ static int class_read(struct policydb *p cladatum->comkey); goto bad; } + + /* + * security_get_permissions() maps the common's permissions + * into an array sized by this class's nprim, so a class must + * declare at least as many as the common it inherits. + */ + if (cladatum->permissions.nprim < + cladatum->comdatum->permissions.nprim) { + pr_err("SELinux: class %s has fewer permissions than common %s\n", + key, cladatum->comkey); + goto bad; + } } for (i = 0; i < nel; i++) { rc = perm_read(p, &cladatum->permissions, fp);