This factors out the part of the vfs_setxattr function that performs the
setting of the xattr and its notification. This is needed so the SELinux
implementation of inode_setsecctx can handle the setting of it's xattr while
maintaining the proper separation of layers.
Signed-off-by: Matthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
---
fs/xattr.c | 55 +++++++++++++++++++++++++++++++++++++-----------
include/linux/xattr.h | 1 +
2 files changed, 43 insertions(+), 13 deletions(-)
diff --git a/fs/xattr.c b/fs/xattr.c
index 468377e..2f93006 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -66,22 +66,28 @@ xattr_permission(struct inode *inode, const char *name, int mask)
return inode_permission(inode, mask);
}
-int
-vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
- size_t size, int flags)
+/**
+ * __vfs_setxattr_noperm - perform setxattr operation without performing
+ * permission checks.
+ *
+ * @dentry - object to perform setxattr on
+ * @name - xattr name to set
+ * @value - value to set @name to
+ * @size - size of @value
+ * @flags - flags to pass into filesystem operations
+ *
+ * returns the result of the internal setxattr or setsecurity operations.
+ *
+ * This function requires the caller to lock the inode's i_mutex before it
+ * is executed. It also assumes that the caller will make the appropriate
+ * permission checks.
+ */
+int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
+ const void *value, size_t size, int flags)
{
struct inode *inode = dentry->d_inode;
- int error;
-
- error = xattr_permission(inode, name, MAY_WRITE);
- if (error)
- return error;
+ int error = -EOPNOTSUPP;
- mutex_lock(&inode->i_mutex);
- error = security_inode_setxattr(dentry, name, value, size, flags);
- if (error)
- goto out;
- error = -EOPNOTSUPP;
if (inode->i_op->setxattr) {
error = inode->i_op->setxattr(dentry, name, value, size, flags);
if (!error) {
@@ -97,6 +103,29 @@ vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
if (!error)
fsnotify_xattr(dentry);
}
+
+ return error;
+}
+
+
+int
+vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
+ size_t size, int flags)
+{
+ struct inode *inode = dentry->d_inode;
+ int error;
+
+ error = xattr_permission(inode, name, MAY_WRITE);
+ if (error)
+ return error;
+
+ mutex_lock(&inode->i_mutex);
+ error = security_inode_setxattr(dentry, name, value, size, flags);
+ if (error)
+ goto out;
+
+ error = __vfs_setxattr_noperm(dentry, name, value, size, flags);
+
out:
mutex_unlock(&inode->i_mutex);
return error;
diff --git a/include/linux/xattr.h b/include/linux/xattr.h
index d131e35..5c84af8 100644
--- a/include/linux/xattr.h
+++ b/include/linux/xattr.h
@@ -49,6 +49,7 @@ struct xattr_handler {
ssize_t xattr_getsecurity(struct inode *, const char *, void *, size_t);
ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t);
ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);
+int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int);
int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int);
int vfs_removexattr(struct dentry *, const char *);
--
1.5.5.1
--
