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 4893235C1A0; Tue, 16 Dec 2025 12:05:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765886744; cv=none; b=rVZ/jlovqkbQfUeahW+CCClI1Juy2eE3LPoBXbS9wXFvGfQmvt1vq2NJf09QIfCl6xIfYUQWD+a7gHxnv3av2zuCwdkZPMyDOjW/P8Ugrss0m44snGa38LDvukOfsfRfqqVPcmT7XCt4wWJwBy/u55KjK6iVpx7ymA5Ym+v7Pc4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765886744; c=relaxed/simple; bh=XCdzSuNnk76+9hEwcKwsMhthWMPJOpbmcntQrJH7QuY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=N5IVuc1W0g/iGR60i0RiSg0fSHnHKiNoM0/MJf0ejXa4nY9TvlwPqVWp2jSf/pm6Wr4y06JwnFiPf7w7IsB0397lGVCsWT6QMAGIvU0+h1pNh7tvDAcHykozF0emftemEPeTDgpqQ8Hzy0Hz+ytMmLU6FJuMUc5L6QGPDD/DrAI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=d5thTAo6; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="d5thTAo6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D904C4CEF1; Tue, 16 Dec 2025 12:05:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1765886743; bh=XCdzSuNnk76+9hEwcKwsMhthWMPJOpbmcntQrJH7QuY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=d5thTAo6sQmpXroTOSi9MluxEy+FP0t6w4qPh9PQIeEFwzMH24XPJ2RaLvbT66N+x EgP7dkNNC8TJcsYTYqyTdpOF3zrjWbdzWoXCEOIraPz+NcuRAg+rLXF0sofOIh2a9l a+208v/OWMuUngjB2vyHKBH+JqV0sTMxu+2kVdyk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Konstantin Andreev , Casey Schaufler , Sasha Levin Subject: [PATCH 6.18 002/614] smack: deduplicate "does access rule request transmutation" Date: Tue, 16 Dec 2025 12:06:09 +0100 Message-ID: <20251216111401.379511902@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251216111401.280873349@linuxfoundation.org> References: <20251216111401.280873349@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Konstantin Andreev [ Upstream commit 635a01da8385fc00a144ec24684100bd1aa9db11 ] Signed-off-by: Konstantin Andreev Signed-off-by: Casey Schaufler Stable-dep-of: 78fc6a94be25 ("smack: fix bug: invalid label of unix socket file") Signed-off-by: Sasha Levin --- security/smack/smack_lsm.c | 57 +++++++++++++++++++++----------------- 1 file changed, 32 insertions(+), 25 deletions(-) diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 39a4caeb6bc8e..a005f5afb8e0d 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -962,6 +962,24 @@ static int smack_inode_alloc_security(struct inode *inode) return 0; } +/** + * smk_rule_transmutes - does access rule for (subject,object) contain 't'? + * @subject: a pointer to the subject's Smack label entry + * @object: a pointer to the object's Smack label entry + */ +static bool +smk_rule_transmutes(struct smack_known *subject, + const struct smack_known *object) +{ + int may; + + rcu_read_lock(); + may = smk_access_entry(subject->smk_known, object->smk_known, + &subject->smk_rules); + rcu_read_unlock(); + return (may > 0) && (may & MAY_TRANSMUTE); +} + /** * smack_inode_init_security - copy out the smack from an inode * @inode: the newly created inode @@ -977,23 +995,19 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, struct xattr *xattrs, int *xattr_count) { struct task_smack *tsp = smack_cred(current_cred()); - struct inode_smack *issp = smack_inode(inode); - struct smack_known *skp = smk_of_task(tsp); - struct smack_known *isp = smk_of_inode(inode); + struct inode_smack * const issp = smack_inode(inode); struct smack_known *dsp = smk_of_inode(dir); struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); - int may; + bool trans_cred; + bool trans_rule; /* * If equal, transmuting already occurred in * smack_dentry_create_files_as(). No need to check again. */ - if (tsp->smk_task != tsp->smk_transmuted) { - rcu_read_lock(); - may = smk_access_entry(skp->smk_known, dsp->smk_known, - &skp->smk_rules); - rcu_read_unlock(); - } + trans_cred = (tsp->smk_task == tsp->smk_transmuted); + if (!trans_cred) + trans_rule = smk_rule_transmutes(smk_of_task(tsp), dsp); /* * In addition to having smk_task equal to smk_transmuted, @@ -1001,9 +1015,7 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, * requests transmutation then by all means transmute. * Mark the inode as changed. */ - if ((tsp->smk_task == tsp->smk_transmuted) || - (may > 0 && ((may & MAY_TRANSMUTE) != 0) && - smk_inode_transmutable(dir))) { + if (trans_cred || (trans_rule && smk_inode_transmutable(dir))) { struct xattr *xattr_transmute; /* @@ -1012,8 +1024,8 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, * inode label was already set correctly in * smack_inode_alloc_security(). */ - if (tsp->smk_task != tsp->smk_transmuted) - isp = issp->smk_inode = dsp; + if (!trans_cred) + issp->smk_inode = dsp; if (S_ISDIR(inode->i_mode)) { issp->smk_flags |= SMK_INODE_TRANSMUTE; @@ -1035,11 +1047,13 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, issp->smk_flags |= SMK_INODE_INSTANT; if (xattr) { - xattr->value = kstrdup(isp->smk_known, GFP_NOFS); + const char *inode_label = issp->smk_inode->smk_known; + + xattr->value = kstrdup(inode_label, GFP_NOFS); if (!xattr->value) return -ENOMEM; - xattr->value_len = strlen(isp->smk_known); + xattr->value_len = strlen(inode_label); xattr->name = XATTR_SMACK_SUFFIX; } @@ -4917,7 +4931,6 @@ static int smack_dentry_create_files_as(struct dentry *dentry, int mode, struct task_smack *otsp = smack_cred(old); struct task_smack *ntsp = smack_cred(new); struct inode_smack *isp; - int may; /* * Use the process credential unless all of @@ -4931,18 +4944,12 @@ static int smack_dentry_create_files_as(struct dentry *dentry, int mode, isp = smack_inode(d_inode(dentry->d_parent)); if (isp->smk_flags & SMK_INODE_TRANSMUTE) { - rcu_read_lock(); - may = smk_access_entry(otsp->smk_task->smk_known, - isp->smk_inode->smk_known, - &otsp->smk_task->smk_rules); - rcu_read_unlock(); - /* * If the directory is transmuting and the rule * providing access is transmuting use the containing * directory label instead of the process label. */ - if (may > 0 && (may & MAY_TRANSMUTE)) { + if (smk_rule_transmutes(otsp->smk_task, isp->smk_inode)) { ntsp->smk_task = isp->smk_inode; ntsp->smk_transmuted = ntsp->smk_task; } -- 2.51.0