linux-kernel - [Patch 1/2] selinux: ajust rules for ATTR

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20090817071011.5913.69970.sendpatchset@localhost.localdomain>
Date:	Mon, 17 Aug 2009 03:07:47 -0400
From:	Amerigo Wang <amwang@...hat.com>
To:	linux-kernel@...r.kernel.org
Cc:	esandeen@...hat.com, eteo@...hat.com, eparis@...hat.com,
	Amerigo Wang <amwang@...hat.com>,
	linux-fsdevel@...r.kernel.org, akpm@...ux-foundation.org,
	sds@...ho.nsa.gov, hirofumi@...l.parknet.co.jp,
	viro@...iv.linux.org.uk
Subject: [Patch 1/2] selinux: ajust rules for ATTR_FORCE


As suggested by OGAWA Hirofumi in thread: http://lkml.org/lkml/2009/8/7/132,
we should let selinux_inode_setattr() to match our ATTR_* rules.
ATTR_FORCE should not force things like ATTR_SIZE.

Cc: OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>
Cc: Stephen Smalley <sds@...ho.nsa.gov>
Cc: Eric Paris <eparis@...hat.com>
Signed-off-by: WANG Cong <amwang@...hat.com>

---
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 1e8cfc4..3ee3365 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2708,18 +2708,24 @@ static int selinux_inode_permission(struct inode *inode, int mask)
 			      file_mask_to_av(inode->i_mode, mask), NULL);
 }
 
+#define SELINUX_FORCED_MASK	(ATTR_MODE | ATTR_UID | ATTR_GID | \
+				ATTR_ATIME_SET | ATTR_MTIME_SET)
 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
 {
 	const struct cred *cred = current_cred();
+	unsigned int ia_valid = iattr->ia_valid;
+	int err = 0;
 
-	if (iattr->ia_valid & ATTR_FORCE)
-		return 0;
-
-	if (iattr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
-			       ATTR_ATIME_SET | ATTR_MTIME_SET))
-		return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
-
-	return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
+	if ((ia_valid & ATTR_FORCE) && (ia_valid & SELINUX_FORCED_MASK)) {
+		err = dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
+		if (err)
+			return err;
+		ia_valid &= ~SELINUX_FORCED_MASK;
+		ia_valid &= ~ATTR_FORCE;
+	}
+	if (ia_valid)
+		err = dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
+	return err;
 }
 
 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/