xattr: Constify ->name member of "struct xattr".

Since everybody sets kstrdup()ed constant string to "struct xattr"->name but
nobody modifies "struct xattr"->name , we can omit kstrdup() and its failure
checking by constifying ->name member of "struct xattr".

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Joel Becker <jlbec@evilplan.org> [ocfs2]
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Reviewed-by: Paul Moore <paul@paul-moore.com>
Tested-by: Paul Moore <paul@paul-moore.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

9 files changed, 21 insertions, 31 deletions

diff --git a/fs/ocfs2/xattr.h b/fs/ocfs2/xattr.h
index e5c7f15465b4..19f134e896a9 100644
--- a/fs/ocfs2/xattr.h
+++ b/fs/ocfs2/xattr.h
@@ -32,7 +32,7 @@ enum ocfs2_xattr_type {
 
 struct ocfs2_security_xattr_info {
         int enable;
-        char *name;
+        const char *name;
         void *value;
         size_t value_len;
 };
diff --git a/include/linux/security.h b/include/linux/security.h
index 7ce53ae1266b..9d37e2b9d3ec 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -1492,7 +1492,7 @@ struct security_operations {
         int (*inode_alloc_security) (struct inode *inode);
         void (*inode_free_security) (struct inode *inode);
         int (*inode_init_security) (struct inode *inode, struct inode *dir,
-                                    const struct qstr *qstr, char **name,
+                                    const struct qstr *qstr, const char **name,
                                     void **value, size_t *len);
         int (*inode_create) (struct inode *dir,
                              struct dentry *dentry, umode_t mode);
@@ -1770,7 +1770,7 @@ int security_inode_init_security(struct inode *inode, struct inode *dir,
                                  const struct qstr *qstr,
                                  initxattrs initxattrs, void *fs_data);
 int security_old_inode_init_security(struct inode *inode, struct inode *dir,
-                                     const struct qstr *qstr, char **name,
+                                     const struct qstr *qstr, const char **name,
                                      void **value, size_t *len);
 int security_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode);
 int security_inode_link(struct dentry *old_dentry, struct inode *dir,
@@ -2094,8 +2094,8 @@ static inline int security_inode_init_security(struct inode *inode,
 static inline int security_old_inode_init_security(struct inode *inode,
                                                    struct inode *dir,
                                                    const struct qstr *qstr,
-                                                   char **name, void **value,
-                                                   size_t *len)
+                                                   const char **name,
+                                                   void **value, size_t *len)
 {
         return -EOPNOTSUPP;
 }
diff --git a/include/linux/xattr.h b/include/linux/xattr.h
index fdbafc6841cf..91b0a68d38dc 100644
--- a/include/linux/xattr.h
+++ b/include/linux/xattr.h
@@ -31,7 +31,7 @@ struct xattr_handler {
 };
 
 struct xattr {
-        char *name;
+        const char *name;
         void *value;
         size_t value_len;
 };
diff --git a/include/uapi/linux/reiserfs_xattr.h b/include/uapi/linux/reiserfs_xattr.h
index d8ce17c2459a..38fdd648be21 100644
--- a/include/uapi/linux/reiserfs_xattr.h
+++ b/include/uapi/linux/reiserfs_xattr.h
@@ -16,7 +16,7 @@ struct reiserfs_xattr_header {
 };
 
 struct reiserfs_security_handle {
-        char *name;
+        const char *name;
         void *value;
         size_t length;
 };
diff --git a/security/capability.c b/security/capability.c
index 32b515766df1..dbeb9bc27b24 100644
--- a/security/capability.c
+++ b/security/capability.c
@@ -129,7 +129,7 @@ static void cap_inode_free_security(struct inode *inode)
 }
 
 static int cap_inode_init_security(struct inode *inode, struct inode *dir,
-                                   const struct qstr *qstr, char **name,
+                                   const struct qstr *qstr, const char **name,
                                    void **value, size_t *len)
 {
         return -EOPNOTSUPP;
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index df0fa451a871..af9b6852f4e1 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -418,7 +418,7 @@ int evm_inode_init_security(struct inode *inode,
 
         evm_xattr->value = xattr_data;
         evm_xattr->value_len = sizeof(*xattr_data);
-        evm_xattr->name = kstrdup(XATTR_EVM_SUFFIX, GFP_NOFS);
+        evm_xattr->name = XATTR_EVM_SUFFIX;
         return 0;
 out:
         kfree(xattr_data);
diff --git a/security/security.c b/security/security.c
index 94b35aef6871..4dc31f4f2700 100644
--- a/security/security.c
+++ b/security/security.c
@@ -348,10 +348,10 @@ int security_inode_init_security(struct inode *inode, struct inode *dir,
         if (unlikely(IS_PRIVATE(inode)))
                 return 0;
 
-        memset(new_xattrs, 0, sizeof new_xattrs);
         if (!initxattrs)
                 return security_ops->inode_init_security(inode, dir, qstr,
                                                          NULL, NULL, NULL);
+        memset(new_xattrs, 0, sizeof(new_xattrs));
         lsm_xattr = new_xattrs;
         ret = security_ops->inode_init_security(inode, dir, qstr,
                                                 &lsm_xattr->name,
@@ -366,16 +366,14 @@ int security_inode_init_security(struct inode *inode, struct inode *dir,
                 goto out;
         ret = initxattrs(inode, new_xattrs, fs_data);
 out:
-        for (xattr = new_xattrs; xattr->name != NULL; xattr++) {
-                kfree(xattr->name);
+        for (xattr = new_xattrs; xattr->value != NULL; xattr++)
                 kfree(xattr->value);
-        }
         return (ret == -EOPNOTSUPP) ? 0 : ret;
 }
 EXPORT_SYMBOL(security_inode_init_security);
 
 int security_old_inode_init_security(struct inode *inode, struct inode *dir,
-                                     const struct qstr *qstr, char **name,
+                                     const struct qstr *qstr, const char **name,
                                      void **value, size_t *len)
 {
         if (unlikely(IS_PRIVATE(inode)))
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index c956390a9136..a5091ec06aa6 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2587,7 +2587,8 @@ static int selinux_dentry_init_security(struct dentry *dentry, int mode,
 }
 
 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
-                                       const struct qstr *qstr, char **name,
+                                       const struct qstr *qstr,
+                                       const char **name,
                                        void **value, size_t *len)
 {
         const struct task_security_struct *tsec = current_security();
@@ -2595,7 +2596,7 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
         struct superblock_security_struct *sbsec;
         u32 sid, newsid, clen;
         int rc;
-        char *namep = NULL, *context;
+        char *context;
 
         dsec = dir->i_security;
         sbsec = dir->i_sb->s_security;
@@ -2631,19 +2632,13 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
                 return -EOPNOTSUPP;
 
-        if (name) {
-                namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
-                if (!namep)
-                        return -ENOMEM;
-                *name = namep;
-        }
+        if (name)
+                *name = XATTR_SELINUX_SUFFIX;
 
         if (value && len) {
                 rc = security_sid_to_context_force(newsid, &context, &clen);
-                if (rc) {
-                        kfree(namep);
+                if (rc)
                         return rc;
-                }
                 *value = context;
                 *len = clen;
         }
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 3f7682a387b7..a113a779f00c 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -582,7 +582,7 @@ static void smack_inode_free_security(struct inode *inode)
  * Returns 0 if it all works out, -ENOMEM if there's no memory
  */
 static int smack_inode_init_security(struct inode *inode, struct inode *dir,
-                                     const struct qstr *qstr, char **name,
+                                     const struct qstr *qstr, const char **name,
                                      void **value, size_t *len)
 {
         struct inode_smack *issp = inode->i_security;
@@ -591,11 +591,8 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir,
         char *dsp = smk_of_inode(dir);
         int may;
 
-        if (name) {
-                *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_NOFS);
-                if (*name == NULL)
-                        return -ENOMEM;
-        }
+        if (name)
+                *name = XATTR_SMACK_SUFFIX;
 
         if (value) {
                 rcu_read_lock();