sanitize xattr handler prototypes

Add a flags argument to struct xattr_handler and pass it to all xattr
handler methods.  This allows using the same methods for multiple
handlers, e.g. for the ACL methods which perform exactly the same action
for the access and default ACLs, just using a different underlying
attribute.  With a little more groundwork it'll also allow sharing the
methods for the regular user/trusted/secure handlers in extN, ocfs2 and
jffs2 like it's already done for xfs in this patch.

Also change the inode argument to the handlers to a dentry to allow
using the handlers mechnism for filesystems that require it later,
e.g. cifs.

[with GFS2 bits updated by Steven Whitehouse <swhiteho@redhat.com>]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

5 files changed, 61 insertions, 86 deletions

diff --git a/fs/ext2/acl.c b/fs/ext2/acl.c
index a63d442..a99e543 100644
--- a/fs/ext2/acl.c
+++ b/fs/ext2/acl.c
@@ -339,12 +339,12 @@ ext2_acl_chmod(struct inode *inode)
  * Extended attribut handlers
  */
 static size_t
-ext2_xattr_list_acl_access(struct inode *inode, char *list, size_t list_size,
-			   const char *name, size_t name_len)
+ext2_xattr_list_acl_access(struct dentry *dentry, char *list, size_t list_size,
+			   const char *name, size_t name_len, int type)
 {
 	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
 
-	if (!test_opt(inode->i_sb, POSIX_ACL))
+	if (!test_opt(dentry->d_sb, POSIX_ACL))
 		return 0;
 	if (list && size <= list_size)
 		memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
@@ -352,12 +352,12 @@ ext2_xattr_list_acl_access(struct inode *inode, char *list, size_t list_size,
 }
 
 static size_t
-ext2_xattr_list_acl_default(struct inode *inode, char *list, size_t list_size,
-			    const char *name, size_t name_len)
+ext2_xattr_list_acl_default(struct dentry *dentry, char *list, size_t list_size,
+			    const char *name, size_t name_len, int type)
 {
 	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
 
-	if (!test_opt(inode->i_sb, POSIX_ACL))
+	if (!test_opt(dentry->d_sb, POSIX_ACL))
 		return 0;
 	if (list && size <= list_size)
 		memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
@@ -365,15 +365,18 @@ ext2_xattr_list_acl_default(struct inode *inode, char *list, size_t list_size,
 }
 
 static int
-ext2_xattr_get_acl(struct inode *inode, int type, void *buffer, size_t size)
+ext2_xattr_get_acl(struct dentry *dentry, const char *name, void *buffer,
+		   size_t size, int type)
 {
 	struct posix_acl *acl;
 	int error;
 
-	if (!test_opt(inode->i_sb, POSIX_ACL))
+	if (strcmp(name, "") != 0)
+		return -EINVAL;
+	if (!test_opt(dentry->d_sb, POSIX_ACL))
 		return -EOPNOTSUPP;
 
-	acl = ext2_get_acl(inode, type);
+	acl = ext2_get_acl(dentry->d_inode, type);
 	if (IS_ERR(acl))
 		return PTR_ERR(acl);
 	if (acl == NULL)
@@ -385,33 +388,17 @@ ext2_xattr_get_acl(struct inode *inode, int type, void *buffer, size_t size)
 }
 
 static int
-ext2_xattr_get_acl_access(struct inode *inode, const char *name,
-			  void *buffer, size_t size)
-{
-	if (strcmp(name, "") != 0)
-		return -EINVAL;
-	return ext2_xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
-}
-
-static int
-ext2_xattr_get_acl_default(struct inode *inode, const char *name,
-			   void *buffer, size_t size)
-{
-	if (strcmp(name, "") != 0)
-		return -EINVAL;
-	return ext2_xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
-}
-
-static int
-ext2_xattr_set_acl(struct inode *inode, int type, const void *value,
-		   size_t size)
+ext2_xattr_set_acl(struct dentry *dentry, const char *name, const void *value,
+		   size_t size, int flags, int type)
 {
 	struct posix_acl *acl;
 	int error;
 
-	if (!test_opt(inode->i_sb, POSIX_ACL))
+	if (strcmp(name, "") != 0)
+		return -EINVAL;
+	if (!test_opt(dentry->d_sb, POSIX_ACL))
 		return -EOPNOTSUPP;
-	if (!is_owner_or_cap(inode))
+	if (!is_owner_or_cap(dentry->d_inode))
 		return -EPERM;
 
 	if (value) {
@@ -426,41 +413,25 @@ ext2_xattr_set_acl(struct inode *inode, int type, const void *value,
 	} else
 		acl = NULL;
 
-	error = ext2_set_acl(inode, type, acl);
+	error = ext2_set_acl(dentry->d_inode, type, acl);
 
 release_and_out:
 	posix_acl_release(acl);
 	return error;
 }
 
-static int
-ext2_xattr_set_acl_access(struct inode *inode, const char *name,
-			  const void *value, size_t size, int flags)
-{
-	if (strcmp(name, "") != 0)
-		return -EINVAL;
-	return ext2_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
-}
-
-static int
-ext2_xattr_set_acl_default(struct inode *inode, const char *name,
-			   const void *value, size_t size, int flags)
-{
-	if (strcmp(name, "") != 0)
-		return -EINVAL;
-	return ext2_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
-}
-
 struct xattr_handler ext2_xattr_acl_access_handler = {
 	.prefix	= POSIX_ACL_XATTR_ACCESS,
+	.flags	= ACL_TYPE_ACCESS,
 	.list	= ext2_xattr_list_acl_access,
-	.get	= ext2_xattr_get_acl_access,
-	.set	= ext2_xattr_set_acl_access,
+	.get	= ext2_xattr_get_acl,
+	.set	= ext2_xattr_set_acl,
 };
 
 struct xattr_handler ext2_xattr_acl_default_handler = {
 	.prefix	= POSIX_ACL_XATTR_DEFAULT,
+	.flags	= ACL_TYPE_DEFAULT,
 	.list	= ext2_xattr_list_acl_default,
-	.get	= ext2_xattr_get_acl_default,
-	.set	= ext2_xattr_set_acl_default,
+	.get	= ext2_xattr_get_acl,
+	.set	= ext2_xattr_set_acl,
 };
diff --git a/fs/ext2/xattr.c b/fs/ext2/xattr.c
index 7913531..904f006 100644
--- a/fs/ext2/xattr.c
+++ b/fs/ext2/xattr.c
@@ -60,6 +60,7 @@
 #include <linux/mbcache.h>
 #include <linux/quotaops.h>
 #include <linux/rwsem.h>
+#include <linux/security.h>
 #include "ext2.h"
 #include "xattr.h"
 #include "acl.h"
@@ -249,8 +250,9 @@ cleanup:
  * used / required on success.
  */
 static int
-ext2_xattr_list(struct inode *inode, char *buffer, size_t buffer_size)
+ext2_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size)
 {
+	struct inode *inode = dentry->d_inode;
 	struct buffer_head *bh = NULL;
 	struct ext2_xattr_entry *entry;
 	char *end;
@@ -300,9 +302,10 @@ bad_block:	ext2_error(inode->i_sb, "ext2_xattr_list",
 			ext2_xattr_handler(entry->e_name_index);
 
 		if (handler) {
-			size_t size = handler->list(inode, buffer, rest,
+			size_t size = handler->list(dentry, buffer, rest,
 						    entry->e_name,
-						    entry->e_name_len);
+						    entry->e_name_len,
+						    handler->flags);
 			if (buffer) {
 				if (size > rest) {
 					error = -ERANGE;
@@ -330,7 +333,7 @@ cleanup:
 ssize_t
 ext2_listxattr(struct dentry *dentry, char *buffer, size_t size)
 {
-	return ext2_xattr_list(dentry->d_inode, buffer, size);
+	return ext2_xattr_list(dentry, buffer, size);
 }
 
 /*
diff --git a/fs/ext2/xattr_security.c b/fs/ext2/xattr_security.c
index 70c0dbd..c815584 100644
--- a/fs/ext2/xattr_security.c
+++ b/fs/ext2/xattr_security.c
@@ -11,8 +11,8 @@
 #include "xattr.h"
 
 static size_t
-ext2_xattr_security_list(struct inode *inode, char *list, size_t list_size,
-			 const char *name, size_t name_len)
+ext2_xattr_security_list(struct dentry *dentry, char *list, size_t list_size,
+			 const char *name, size_t name_len, int type)
 {
 	const int prefix_len = XATTR_SECURITY_PREFIX_LEN;
 	const size_t total_len = prefix_len + name_len + 1;
@@ -26,22 +26,22 @@ ext2_xattr_security_list(struct inode *inode, char *list, size_t list_size,
 }
 
 static int
-ext2_xattr_security_get(struct inode *inode, const char *name,
-		       void *buffer, size_t size)
+ext2_xattr_security_get(struct dentry *dentry, const char *name,
+		       void *buffer, size_t size, int type)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
-	return ext2_xattr_get(inode, EXT2_XATTR_INDEX_SECURITY, name,
+	return ext2_xattr_get(dentry->d_inode, EXT2_XATTR_INDEX_SECURITY, name,
 			      buffer, size);
 }
 
 static int
-ext2_xattr_security_set(struct inode *inode, const char *name,
-		       const void *value, size_t size, int flags)
+ext2_xattr_security_set(struct dentry *dentry, const char *name,
+		const void *value, size_t size, int flags, int type)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
-	return ext2_xattr_set(inode, EXT2_XATTR_INDEX_SECURITY, name,
+	return ext2_xattr_set(dentry->d_inode, EXT2_XATTR_INDEX_SECURITY, name,
 			      value, size, flags);
 }
 
diff --git a/fs/ext2/xattr_trusted.c b/fs/ext2/xattr_trusted.c
index e8219f8..2a26d71 100644
--- a/fs/ext2/xattr_trusted.c
+++ b/fs/ext2/xattr_trusted.c
@@ -13,8 +13,8 @@
 #include "xattr.h"
 
 static size_t
-ext2_xattr_trusted_list(struct inode *inode, char *list, size_t list_size,
-			const char *name, size_t name_len)
+ext2_xattr_trusted_list(struct dentry *dentry, char *list, size_t list_size,
+		const char *name, size_t name_len, int type)
 {
 	const int prefix_len = XATTR_TRUSTED_PREFIX_LEN;
 	const size_t total_len = prefix_len + name_len + 1;
@@ -31,22 +31,22 @@ ext2_xattr_trusted_list(struct inode *inode, char *list, size_t list_size,
 }
 
 static int
-ext2_xattr_trusted_get(struct inode *inode, const char *name,
-		       void *buffer, size_t size)
+ext2_xattr_trusted_get(struct dentry *dentry, const char *name,
+		void *buffer, size_t size, int type)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
-	return ext2_xattr_get(inode, EXT2_XATTR_INDEX_TRUSTED, name,
+	return ext2_xattr_get(dentry->d_inode, EXT2_XATTR_INDEX_TRUSTED, name,
 			      buffer, size);
 }
 
 static int
-ext2_xattr_trusted_set(struct inode *inode, const char *name,
-		       const void *value, size_t size, int flags)
+ext2_xattr_trusted_set(struct dentry *dentry, const char *name,
+		const void *value, size_t size, int flags, int type)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
-	return ext2_xattr_set(inode, EXT2_XATTR_INDEX_TRUSTED, name,
+	return ext2_xattr_set(dentry->d_inode, EXT2_XATTR_INDEX_TRUSTED, name,
 			      value, size, flags);
 }
 
diff --git a/fs/ext2/xattr_user.c b/fs/ext2/xattr_user.c
index 92495d2..3f6caf3 100644
--- a/fs/ext2/xattr_user.c
+++ b/fs/ext2/xattr_user.c
@@ -12,13 +12,13 @@
 #include "xattr.h"
 
 static size_t
-ext2_xattr_user_list(struct inode *inode, char *list, size_t list_size,
-		     const char *name, size_t name_len)
+ext2_xattr_user_list(struct dentry *dentry, char *list, size_t list_size,
+		const char *name, size_t name_len, int type)
 {
 	const size_t prefix_len = XATTR_USER_PREFIX_LEN;
 	const size_t total_len = prefix_len + name_len + 1;
 
-	if (!test_opt(inode->i_sb, XATTR_USER))
+	if (!test_opt(dentry->d_sb, XATTR_USER))
 		return 0;
 
 	if (list && total_len <= list_size) {
@@ -30,27 +30,28 @@ ext2_xattr_user_list(struct inode *inode, char *list, size_t list_size,
 }
 
 static int
-ext2_xattr_user_get(struct inode *inode, const char *name,
-		    void *buffer, size_t size)
+ext2_xattr_user_get(struct dentry *dentry, const char *name,
+		void *buffer, size_t size, int type)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
-	if (!test_opt(inode->i_sb, XATTR_USER))
+	if (!test_opt(dentry->d_sb, XATTR_USER))
 		return -EOPNOTSUPP;
-	return ext2_xattr_get(inode, EXT2_XATTR_INDEX_USER, name, buffer, size);
+	return ext2_xattr_get(dentry->d_inode, EXT2_XATTR_INDEX_USER,
+			      name, buffer, size);
 }
 
 static int
-ext2_xattr_user_set(struct inode *inode, const char *name,
-		    const void *value, size_t size, int flags)
+ext2_xattr_user_set(struct dentry *dentry, const char *name,
+		const void *value, size_t size, int flags, int type)
 {
 	if (strcmp(name, "") == 0)
 		return -EINVAL;
-	if (!test_opt(inode->i_sb, XATTR_USER))
+	if (!test_opt(dentry->d_sb, XATTR_USER))
 		return -EOPNOTSUPP;
 
-	return ext2_xattr_set(inode, EXT2_XATTR_INDEX_USER, name,
-			      value, size, flags);
+	return ext2_xattr_set(dentry->d_inode, EXT2_XATTR_INDEX_USER,
+			      name, value, size, flags);
 }
 
 struct xattr_handler ext2_xattr_user_handler = {