Re: [PATCH 1/1] security: introduce fs caps

["Serge E. Hallyn" <serue@us.ibm.com>]

Sorry, I should have noticed and fixed this much sooner.  This
patch is against the latest full fscaps patch which I'm replying
to.

From: Serge E. Hallyn <serue@us.ibm.com>
Date: Thu, 9 Nov 2006 00:01:49 -0600
Subject: security: file caps: fix unused variable warnings

Address warnings of unused variables at cap_bprm_set_security
when file capabilities are disabled, and simultaneously clean
up the code a little, by pulling the new code into a helper
function.

Rename vfs_cap_data_struct to remove redundant '_struct'.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
---
 security/commoncap.c |   73 ++++++++++++++++++++++++++++----------------------
 1 files changed, 41 insertions(+), 32 deletions(-)

diff --git a/security/commoncap.c b/security/commoncap.c
index 6f5e46c..4b50b4d 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -109,16 +109,17 @@ void cap_capset_set (struct task_struct 
 	target->cap_permitted = *permitted;
 }
 
+#ifdef CONFIG_SECURITY_FS_CAPABILITIES
 #define XATTR_CAPS_SUFFIX "capability"
 #define XATTR_NAME_CAPS XATTR_SECURITY_PREFIX XATTR_CAPS_SUFFIX
-struct vfs_cap_data_struct {
+struct vfs_cap_data {
 	__u32 version;
 	__u32 effective;
 	__u32 permitted;
 	__u32 inheritable;
 };
 
-static inline void convert_to_le(struct vfs_cap_data_struct *cap)
+static inline void convert_to_le(struct vfs_cap_data *cap)
 {
 	cap->version = le32_to_cpu(cap->version);
 	cap->effective = le32_to_cpu(cap->effective);
@@ -126,7 +127,7 @@ static inline void convert_to_le(struct 
 	cap->inheritable = le32_to_cpu(cap->inheritable);
 }
 
-static int check_cap_sanity(struct vfs_cap_data_struct *cap)
+static int check_cap_sanity(struct vfs_cap_data *cap)
 {
 	int i;
 
@@ -149,39 +150,14 @@ static int check_cap_sanity(struct vfs_c
 	return 0;
 }
 
-int cap_bprm_set_security (struct linux_binprm *bprm)
+/* Locate any VFS capabilities: */
+static int set_file_caps(struct linux_binprm *bprm)
 {
 	struct dentry *dentry;
 	ssize_t rc;
-	struct vfs_cap_data_struct cap_struct;
+	struct vfs_cap_data cap_struct;
 	struct inode *inode;
 
-	/* Copied from fs/exec.c:prepare_binprm. */
-
-	cap_clear (bprm->cap_inheritable);
-	cap_clear (bprm->cap_permitted);
-	cap_clear (bprm->cap_effective);
-
-	/*  To support inheritance of root-permissions and suid-root
-	 *  executables under compatibility mode, we raise all three
-	 *  capability sets for the file.
-	 *
-	 *  If only the real uid is 0, we only raise the inheritable
-	 *  and permitted sets of the executable file.
-	 */
-
-	if (!issecure (SECURE_NOROOT)) {
-		if (bprm->e_uid == 0 || current->uid == 0) {
-			cap_set_full (bprm->cap_inheritable);
-			cap_set_full (bprm->cap_permitted);
-		}
-		if (bprm->e_uid == 0)
-			cap_set_full (bprm->cap_effective);
-	}
-
-#ifdef CONFIG_SECURITY_FS_CAPABILITIES
-	/* Locate any VFS capabilities: */
-
 	dentry = dget(bprm->file->f_dentry);
 	inode = dentry->d_inode;
 	if (!inode->i_op || !inode->i_op->getxattr) {
@@ -216,9 +192,42 @@ #ifdef CONFIG_SECURITY_FS_CAPABILITIES
 	bprm->cap_permitted = cap_struct.permitted;
 	bprm->cap_inheritable = cap_struct.inheritable;
 
-#endif
 	return 0;
 }
+#else
+static int set_file_caps(struct linux_binprm *bprm)
+{
+	return 0;
+}
+#endif
+
+int cap_bprm_set_security (struct linux_binprm *bprm)
+{
+	/* Copied from fs/exec.c:prepare_binprm. */
+
+	cap_clear (bprm->cap_inheritable);
+	cap_clear (bprm->cap_permitted);
+	cap_clear (bprm->cap_effective);
+
+	/*  To support inheritance of root-permissions and suid-root
+	 *  executables under compatibility mode, we raise all three
+	 *  capability sets for the file.
+	 *
+	 *  If only the real uid is 0, we only raise the inheritable
+	 *  and permitted sets of the executable file.
+	 */
+
+	if (!issecure (SECURE_NOROOT)) {
+		if (bprm->e_uid == 0 || current->uid == 0) {
+			cap_set_full (bprm->cap_inheritable);
+			cap_set_full (bprm->cap_permitted);
+		}
+		if (bprm->e_uid == 0)
+			cap_set_full (bprm->cap_effective);
+	}
+
+	return set_file_caps(bprm);
+}
 
 void cap_bprm_apply_creds (struct linux_binprm *bprm, int unsafe)
 {
-- 
1.4.1