ubifs: Switch to generic xattr handlers

Ubifs internally uses special inodes for storing xattrs. Those inodes
had NULL {get,set,remove}xattr inode operations before this change, so
xattr operations on them would fail. The super block's s_xattr field
would also apply to those special inodes. However, the inodes are not
visible outside of ubifs, and so no xattr operations will ever be
carried out on them anyway.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index 795992a8321e9e0c9531c92f97c91cc10835cc02..4d07d15647808c8a238fe6a49be85d2d12288803 100644 (file)
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -1182,10 +1182,10 @@ const struct inode_operations ubifs_dir_inode_operations = {
        .rename      = ubifs_rename,
        .setattr     = ubifs_setattr,
        .getattr     = ubifs_getattr,
-       .setxattr    = ubifs_setxattr,
-       .getxattr    = ubifs_getxattr,
+       .setxattr    = generic_setxattr,
+       .getxattr    = generic_getxattr,
        .listxattr   = ubifs_listxattr,
-       .removexattr = ubifs_removexattr,
+       .removexattr = generic_removexattr,
 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
        .update_time = ubifs_update_time,
 #endif

diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 065c88f8e4b8c2d689e8fe9ce13122b5465e8f63..e14943736ebf6154ef46fd35aa476526980cade6 100644 (file)
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1597,10 +1597,10 @@ const struct address_space_operations ubifs_file_address_operations = {
 const struct inode_operations ubifs_file_inode_operations = {
        .setattr     = ubifs_setattr,
        .getattr     = ubifs_getattr,
-       .setxattr    = ubifs_setxattr,
-       .getxattr    = ubifs_getxattr,
+       .setxattr    = generic_setxattr,
+       .getxattr    = generic_getxattr,
        .listxattr   = ubifs_listxattr,
-       .removexattr = ubifs_removexattr,
+       .removexattr = generic_removexattr,
 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
        .update_time = ubifs_update_time,
 #endif
@@ -1611,10 +1611,10 @@ const struct inode_operations ubifs_symlink_inode_operations = {
        .get_link    = simple_get_link,
        .setattr     = ubifs_setattr,
        .getattr     = ubifs_getattr,
-       .setxattr    = ubifs_setxattr,
-       .getxattr    = ubifs_getxattr,
+       .setxattr    = generic_setxattr,
+       .getxattr    = generic_getxattr,
        .listxattr   = ubifs_listxattr,
-       .removexattr = ubifs_removexattr,
+       .removexattr = generic_removexattr,
 #ifdef CONFIG_UBIFS_ATIME_SUPPORT
        .update_time = ubifs_update_time,
 #endif

diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index a233ba913be4f0ebe91a56dc5dae9c6c8d01862c..f72f6423f082e584f5c1590d3e894588c091c9ae 100644 (file)
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -2040,6 +2040,7 @@ static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
        if (c->max_inode_sz > MAX_LFS_FILESIZE)
                sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE;
        sb->s_op = &ubifs_super_operations;
+       sb->s_xattr = ubifs_xattr_handlers;
 
        mutex_lock(&c->umount_mutex);
        err = mount_ubifs(c);

diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 536fb495f2f195b5a602fac38712e7da9ce2e29f..05d9fe70cab487397bacd4781d7ec58d06f533e4 100644 (file)
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -37,6 +37,7 @@
 #include <linux/pagemap.h>
 #include <linux/backing-dev.h>
 #include <linux/security.h>
+#include <linux/xattr.h>
 #include "ubifs-media.h"
 
 /* Version of this UBIFS implementation */
@@ -1732,12 +1733,8 @@ int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
                  struct kstat *stat);
 
 /* xattr.c */
-int ubifs_setxattr(struct dentry *dentry, const char *name,
-                  const void *value, size_t size, int flags);
-ssize_t ubifs_getxattr(struct dentry *dentry, struct inode *host,
-                      const char *name, void *buf, size_t size);
+extern const struct xattr_handler *ubifs_xattr_handlers[];
 ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size);
-int ubifs_removexattr(struct dentry *dentry, const char *name);
 int ubifs_init_security(struct inode *dentry, struct inode *inode,
                        const struct qstr *qstr);
 

diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index 413d650c9476d747d1f9f52f34e93a10173e8e56..6c277eb6aef943787a1fd98e74a8ab8f57c63d4b 100644 (file)
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -249,42 +249,6 @@ out_free:
        return err;
 }
 
-/**
- * check_namespace - check extended attribute name-space.
- * @nm: extended attribute name
- *
- * This function makes sure the extended attribute name belongs to one of the
- * supported extended attribute name-spaces. Returns name-space index in case
- * of success and a negative error code in case of failure.
- */
-static int check_namespace(const struct qstr *nm)
-{
-       int type;
-
-       if (nm->len > UBIFS_MAX_NLEN)
-               return -ENAMETOOLONG;
-
-       if (!strncmp(nm->name, XATTR_TRUSTED_PREFIX,
-                    XATTR_TRUSTED_PREFIX_LEN)) {
-               if (nm->name[XATTR_TRUSTED_PREFIX_LEN] == '\0')
-                       return -EINVAL;
-               type = TRUSTED_XATTR;
-       } else if (!strncmp(nm->name, XATTR_USER_PREFIX,
-                                     XATTR_USER_PREFIX_LEN)) {
-               if (nm->name[XATTR_USER_PREFIX_LEN] == '\0')
-                       return -EINVAL;
-               type = USER_XATTR;
-       } else if (!strncmp(nm->name, XATTR_SECURITY_PREFIX,
-                                    XATTR_SECURITY_PREFIX_LEN)) {
-               if (nm->name[XATTR_SECURITY_PREFIX_LEN] == '\0')
-                       return -EINVAL;
-               type = SECURITY_XATTR;
-       } else
-               return -EOPNOTSUPP;
-
-       return type;
-}
-
 static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum)
 {
        struct inode *inode;
@@ -302,24 +266,23 @@ static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum)
        return ERR_PTR(-EINVAL);
 }
 
-static int setxattr(struct inode *host, const char *name, const void *value,
-                   size_t size, int flags)
+static int __ubifs_setxattr(struct inode *host, const char *name,
+                           const void *value, size_t size, int flags)
 {
        struct inode *inode;
        struct ubifs_info *c = host->i_sb->s_fs_info;
        struct qstr nm = QSTR_INIT(name, strlen(name));
        struct ubifs_dent_node *xent;
        union ubifs_key key;
-       int err, type;
+       int err;
 
        ubifs_assert(inode_is_locked(host));
 
        if (size > UBIFS_MAX_INO_DATA)
                return -ERANGE;
 
-       type = check_namespace(&nm);
-       if (type < 0)
-               return type;
+       if (nm.len > UBIFS_MAX_NLEN)
+               return -ENAMETOOLONG;
 
        xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
        if (!xent)
@@ -363,17 +326,8 @@ out_free:
        return err;
 }
 
-int ubifs_setxattr(struct dentry *dentry, const char *name,
-                  const void *value, size_t size, int flags)
-{
-       dbg_gen("xattr '%s', host ino %lu ('%pd'), size %zd",
-               name, d_inode(dentry)->i_ino, dentry, size);
-
-       return setxattr(d_inode(dentry), name, value, size, flags);
-}
-
-ssize_t ubifs_getxattr(struct dentry *dentry, struct inode *host,
-                      const char *name, void *buf, size_t size)
+static ssize_t __ubifs_getxattr(struct inode *host, const char *name,
+                               void *buf, size_t size)
 {
        struct inode *inode;
        struct ubifs_info *c = host->i_sb->s_fs_info;
@@ -383,12 +337,8 @@ ssize_t ubifs_getxattr(struct dentry *dentry, struct inode *host,
        union ubifs_key key;
        int err;
 
-       dbg_gen("xattr '%s', ino %lu ('%pd'), buf size %zd", name,
-               host->i_ino, dentry, size);
-
-       err = check_namespace(&nm);
-       if (err < 0)
-               return err;
+       if (nm.len > UBIFS_MAX_NLEN)
+               return -ENAMETOOLONG;
 
        xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
        if (!xent)
@@ -460,8 +410,6 @@ ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size)
 
        lowest_xent_key(c, &key, host->i_ino);
        while (1) {
-               int type;
-
                xent = ubifs_tnc_next_ent(c, &key, &nm);
                if (IS_ERR(xent)) {
                        err = PTR_ERR(xent);
@@ -471,14 +419,10 @@ ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size)
                nm.name = xent->name;
                nm.len = le16_to_cpu(xent->nlen);
 
-               type = check_namespace(&nm);
-               if (unlikely(type < 0)) {
-                       err = type;
-                       break;
-               }
-
                /* Show trusted namespace only for "power" users */
-               if (type != TRUSTED_XATTR || capable(CAP_SYS_ADMIN)) {
+               if (strncmp(xent->name, XATTR_TRUSTED_PREFIX,
+                           XATTR_TRUSTED_PREFIX_LEN) ||
+                   capable(CAP_SYS_ADMIN)) {
                        memcpy(buffer + written, nm.name, nm.len + 1);
                        written += nm.len + 1;
                }
@@ -538,22 +482,19 @@ out_cancel:
        return err;
 }
 
-int ubifs_removexattr(struct dentry *dentry, const char *name)
+static int __ubifs_removexattr(struct inode *host, const char *name)
 {
-       struct inode *inode, *host = d_inode(dentry);
+       struct inode *inode;
        struct ubifs_info *c = host->i_sb->s_fs_info;
        struct qstr nm = QSTR_INIT(name, strlen(name));
        struct ubifs_dent_node *xent;
        union ubifs_key key;
        int err;
 
-       dbg_gen("xattr '%s', ino %lu ('%pd')", name,
-               host->i_ino, dentry);
        ubifs_assert(inode_is_locked(host));
 
-       err = check_namespace(&nm);
-       if (err < 0)
-               return err;
+       if (nm.len > UBIFS_MAX_NLEN)
+               return -ENAMETOOLONG;
 
        xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
        if (!xent)
@@ -603,7 +544,7 @@ static int init_xattrs(struct inode *inode, const struct xattr *xattr_array,
                }
                strcpy(name, XATTR_SECURITY_PREFIX);
                strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
-               err = setxattr(inode, name, xattr->value, xattr->value_len, 0);
+               err = __ubifs_setxattr(inode, name, xattr->value, xattr->value_len, 0);
                kfree(name);
                if (err < 0)
                        break;
@@ -626,3 +567,53 @@ int ubifs_init_security(struct inode *dentry, struct inode *inode,
        }
        return err;
 }
+
+static int ubifs_xattr_get(const struct xattr_handler *handler,
+                          struct dentry *dentry, struct inode *inode,
+                          const char *name, void *buffer, size_t size)
+{
+       dbg_gen("xattr '%s', ino %lu ('%pd'), buf size %zd", name,
+               inode->i_ino, dentry, size);
+
+       return  __ubifs_getxattr(inode, name, buffer, size);
+}
+
+static int ubifs_xattr_set(const struct xattr_handler *handler,
+                          struct dentry *dentry, const char *name,
+                          const void *value, size_t size, int flags)
+{
+       struct inode *inode = d_inode(dentry);
+
+       dbg_gen("xattr '%s', host ino %lu ('%pd'), size %zd",
+               name, inode->i_ino, dentry, size);
+
+       if (value)
+               return __ubifs_setxattr(inode, name, value, size, flags);
+       else
+               return __ubifs_removexattr(inode, name);
+}
+
+const struct xattr_handler ubifs_user_xattr_handler = {
+       .prefix = XATTR_USER_PREFIX,
+       .get = ubifs_xattr_get,
+       .set = ubifs_xattr_set,
+};
+
+const struct xattr_handler ubifs_trusted_xattr_handler = {
+       .prefix = XATTR_TRUSTED_PREFIX,
+       .get = ubifs_xattr_get,
+       .set = ubifs_xattr_set,
+};
+
+const struct xattr_handler ubifs_security_xattr_handler = {
+       .prefix = XATTR_SECURITY_PREFIX,
+       .get = ubifs_xattr_get,
+       .set = ubifs_xattr_set,
+};
+
+const struct xattr_handler *ubifs_xattr_handlers[] = {
+       &ubifs_user_xattr_handler,
+       &ubifs_trusted_xattr_handler,
+       &ubifs_security_xattr_handler,
+       NULL
+};