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, 70 insertions, 98 deletions

diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
index 58aa8e7..8c7033a 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -48,6 +48,7 @@
 #include <net/checksum.h>
 #include <linux/stat.h>
 #include <linux/quotaops.h>
+#include <linux/security.h>
 
 #define PRIVROOT_NAME ".reiserfs_priv"
 #define XAROOT_NAME   "xattrs"
@@ -726,15 +727,14 @@ ssize_t
 reiserfs_getxattr(struct dentry * dentry, const char *name, void *buffer,
 		  size_t size)
 {
-	struct inode *inode = dentry->d_inode;
 	struct xattr_handler *handler;
 
-	handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
+	handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
 
-	if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
+	if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
 		return -EOPNOTSUPP;
 
-	return handler->get(inode, name, buffer, size);
+	return handler->get(dentry, name, buffer, size, handler->flags);
 }
 
 /*
@@ -746,15 +746,14 @@ int
 reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
 		  size_t size, int flags)
 {
-	struct inode *inode = dentry->d_inode;
 	struct xattr_handler *handler;
 
-	handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
+	handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
 
-	if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
+	if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
 		return -EOPNOTSUPP;
 
-	return handler->set(inode, name, value, size, flags);
+	return handler->set(dentry, name, value, size, flags, handler->flags);
 }
 
 /*
@@ -764,21 +763,20 @@ reiserfs_setxattr(struct dentry *dentry, const char *name, const void *value,
  */
 int reiserfs_removexattr(struct dentry *dentry, const char *name)
 {
-	struct inode *inode = dentry->d_inode;
 	struct xattr_handler *handler;
-	handler = find_xattr_handler_prefix(inode->i_sb->s_xattr, name);
+	handler = find_xattr_handler_prefix(dentry->d_sb->s_xattr, name);
 
-	if (!handler || get_inode_sd_version(inode) == STAT_DATA_V1)
+	if (!handler || get_inode_sd_version(dentry->d_inode) == STAT_DATA_V1)
 		return -EOPNOTSUPP;
 
-	return handler->set(inode, name, NULL, 0, XATTR_REPLACE);
+	return handler->set(dentry, name, NULL, 0, XATTR_REPLACE, handler->flags);
 }
 
 struct listxattr_buf {
 	size_t size;
 	size_t pos;
 	char *buf;
-	struct inode *inode;
+	struct dentry *dentry;
 };
 
 static int listxattr_filler(void *buf, const char *name, int namelen,
@@ -789,17 +787,19 @@ static int listxattr_filler(void *buf, const char *name, int namelen,
 	if (name[0] != '.' ||
 	    (namelen != 1 && (name[1] != '.' || namelen != 2))) {
 		struct xattr_handler *handler;
-		handler = find_xattr_handler_prefix(b->inode->i_sb->s_xattr,
+		handler = find_xattr_handler_prefix(b->dentry->d_sb->s_xattr,
 						    name);
 		if (!handler)	/* Unsupported xattr name */
 			return 0;
 		if (b->buf) {
-			size = handler->list(b->inode, b->buf + b->pos,
-					 b->size, name, namelen);
+			size = handler->list(b->dentry, b->buf + b->pos,
+					 b->size, name, namelen,
+					 handler->flags);
 			if (size > b->size)
 				return -ERANGE;
 		} else {
-			size = handler->list(b->inode, NULL, 0, name, namelen);
+			size = handler->list(b->dentry, NULL, 0, name,
+					     namelen, handler->flags);
 		}
 
 		b->pos += size;
@@ -820,7 +820,7 @@ ssize_t reiserfs_listxattr(struct dentry * dentry, char *buffer, size_t size)
 	int err = 0;
 	loff_t pos = 0;
 	struct listxattr_buf buf = {
-		.inode = dentry->d_inode,
+		.dentry = dentry,
 		.buf = buffer,
 		.size = buffer ? size : 0,
 	};
diff --git a/fs/reiserfs/xattr_acl.c b/fs/reiserfs/xattr_acl.c
index 35d6e67..cc32e6a 100644
--- a/fs/reiserfs/xattr_acl.c
+++ b/fs/reiserfs/xattr_acl.c
@@ -15,8 +15,10 @@ static int reiserfs_set_acl(struct reiserfs_transaction_handle *th,
 			    struct posix_acl *acl);
 
 static int
-xattr_set_acl(struct inode *inode, int type, const void *value, size_t size)
+posix_acl_set(struct dentry *dentry, const char *name, const void *value,
+		size_t size, int flags, int type)
 {
+	struct inode *inode = dentry->d_inode;
 	struct posix_acl *acl;
 	int error, error2;
 	struct reiserfs_transaction_handle th;
@@ -60,15 +62,16 @@ xattr_set_acl(struct inode *inode, int type, const void *value, size_t size)
 }
 
 static int
-xattr_get_acl(struct inode *inode, int type, void *buffer, size_t size)
+posix_acl_get(struct dentry *dentry, const char *name, void *buffer,
+		size_t size, int type)
 {
 	struct posix_acl *acl;
 	int error;
 
-	if (!reiserfs_posixacl(inode->i_sb))
+	if (!reiserfs_posixacl(dentry->d_sb))
 		return -EOPNOTSUPP;
 
-	acl = reiserfs_get_acl(inode, type);
+	acl = reiserfs_get_acl(dentry->d_inode, type);
 	if (IS_ERR(acl))
 		return PTR_ERR(acl);
 	if (acl == NULL)
@@ -482,30 +485,12 @@ int reiserfs_acl_chmod(struct inode *inode)
 	return error;
 }
 
-static int
-posix_acl_access_get(struct inode *inode, const char *name,
-		     void *buffer, size_t size)
-{
-	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
-		return -EINVAL;
-	return xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
-}
-
-static int
-posix_acl_access_set(struct inode *inode, const char *name,
-		     const void *value, size_t size, int flags)
-{
-	if (strlen(name) != sizeof(POSIX_ACL_XATTR_ACCESS) - 1)
-		return -EINVAL;
-	return xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
-}
-
-static size_t posix_acl_access_list(struct inode *inode, char *list,
+static size_t posix_acl_access_list(struct dentry *dentry, char *list,
 				    size_t list_size, const char *name,
-				    size_t name_len)
+				    size_t name_len, int type)
 {
 	const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
-	if (!reiserfs_posixacl(inode->i_sb))
+	if (!reiserfs_posixacl(dentry->d_sb))
 		return 0;
 	if (list && size <= list_size)
 		memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
@@ -514,35 +499,18 @@ static size_t posix_acl_access_list(struct inode *inode, char *list,
 
 struct xattr_handler reiserfs_posix_acl_access_handler = {
 	.prefix = POSIX_ACL_XATTR_ACCESS,
-	.get = posix_acl_access_get,
-	.set = posix_acl_access_set,
+	.flags = ACL_TYPE_ACCESS,
+	.get = posix_acl_get,
+	.set = posix_acl_set,
 	.list = posix_acl_access_list,
 };
 
-static int
-posix_acl_default_get(struct inode *inode, const char *name,
-		      void *buffer, size_t size)
-{
-	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
-		return -EINVAL;
-	return xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
-}
-
-static int
-posix_acl_default_set(struct inode *inode, const char *name,
-		      const void *value, size_t size, int flags)
-{
-	if (strlen(name) != sizeof(POSIX_ACL_XATTR_DEFAULT) - 1)
-		return -EINVAL;
-	return xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
-}
-
-static size_t posix_acl_default_list(struct inode *inode, char *list,
+static size_t posix_acl_default_list(struct dentry *dentry, char *list,
 				     size_t list_size, const char *name,
-				     size_t name_len)
+				     size_t name_len, int type)
 {
 	const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
-	if (!reiserfs_posixacl(inode->i_sb))
+	if (!reiserfs_posixacl(dentry->d_sb))
 		return 0;
 	if (list && size <= list_size)
 		memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
@@ -551,7 +519,8 @@ static size_t posix_acl_default_list(struct inode *inode, char *list,
 
 struct xattr_handler reiserfs_posix_acl_default_handler = {
 	.prefix = POSIX_ACL_XATTR_DEFAULT,
-	.get = posix_acl_default_get,
-	.set = posix_acl_default_set,
+	.flags = ACL_TYPE_DEFAULT,
+	.get = posix_acl_get,
+	.set = posix_acl_set,
 	.list = posix_acl_default_list,
 };
diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c
index a92c879..d8b5bfc 100644
--- a/fs/reiserfs/xattr_security.c
+++ b/fs/reiserfs/xattr_security.c
@@ -8,36 +8,37 @@
 #include <asm/uaccess.h>
 
 static int
-security_get(struct inode *inode, const char *name, void *buffer, size_t size)
+security_get(struct dentry *dentry, const char *name, void *buffer, size_t size,
+		int handler_flags)
 {
 	if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
 		return -EINVAL;
 
-	if (IS_PRIVATE(inode))
+	if (IS_PRIVATE(dentry->d_inode))
 		return -EPERM;
 
-	return reiserfs_xattr_get(inode, name, buffer, size);
+	return reiserfs_xattr_get(dentry->d_inode, name, buffer, size);
 }
 
 static int
-security_set(struct inode *inode, const char *name, const void *buffer,
-	     size_t size, int flags)
+security_set(struct dentry *dentry, const char *name, const void *buffer,
+	     size_t size, int flags, int handler_flags)
 {
 	if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
 		return -EINVAL;
 
-	if (IS_PRIVATE(inode))
+	if (IS_PRIVATE(dentry->d_inode))
 		return -EPERM;
 
-	return reiserfs_xattr_set(inode, name, buffer, size, flags);
+	return reiserfs_xattr_set(dentry->d_inode, name, buffer, size, flags);
 }
 
-static size_t security_list(struct inode *inode, char *list, size_t list_len,
-			    const char *name, size_t namelen)
+static size_t security_list(struct dentry *dentry, char *list, size_t list_len,
+			    const char *name, size_t namelen, int handler_flags)
 {
 	const size_t len = namelen + 1;
 
-	if (IS_PRIVATE(inode))
+	if (IS_PRIVATE(dentry->d_inode))
 		return 0;
 
 	if (list && len <= list_len) {
diff --git a/fs/reiserfs/xattr_trusted.c b/fs/reiserfs/xattr_trusted.c
index a865042..5b08aac 100644
--- a/fs/reiserfs/xattr_trusted.c
+++ b/fs/reiserfs/xattr_trusted.c
@@ -8,36 +8,37 @@
 #include <asm/uaccess.h>
 
 static int
-trusted_get(struct inode *inode, const char *name, void *buffer, size_t size)
+trusted_get(struct dentry *dentry, const char *name, void *buffer, size_t size,
+	    int handler_flags)
 {
 	if (strlen(name) < sizeof(XATTR_TRUSTED_PREFIX))
 		return -EINVAL;
 
-	if (!capable(CAP_SYS_ADMIN) || IS_PRIVATE(inode))
+	if (!capable(CAP_SYS_ADMIN) || IS_PRIVATE(dentry->d_inode))
 		return -EPERM;
 
-	return reiserfs_xattr_get(inode, name, buffer, size);
+	return reiserfs_xattr_get(dentry->d_inode, name, buffer, size);
 }
 
 static int
-trusted_set(struct inode *inode, const char *name, const void *buffer,
-	    size_t size, int flags)
+trusted_set(struct dentry *dentry, const char *name, const void *buffer,
+	    size_t size, int flags, int handler_flags)
 {
 	if (strlen(name) < sizeof(XATTR_TRUSTED_PREFIX))
 		return -EINVAL;
 
-	if (!capable(CAP_SYS_ADMIN) || IS_PRIVATE(inode))
+	if (!capable(CAP_SYS_ADMIN) || IS_PRIVATE(dentry->d_inode))
 		return -EPERM;
 
-	return reiserfs_xattr_set(inode, name, buffer, size, flags);
+	return reiserfs_xattr_set(dentry->d_inode, name, buffer, size, flags);
 }
 
-static size_t trusted_list(struct inode *inode, char *list, size_t list_size,
-			   const char *name, size_t name_len)
+static size_t trusted_list(struct dentry *dentry, char *list, size_t list_size,
+			   const char *name, size_t name_len, int handler_flags)
 {
 	const size_t len = name_len + 1;
 
-	if (!capable(CAP_SYS_ADMIN) || IS_PRIVATE(inode))
+	if (!capable(CAP_SYS_ADMIN) || IS_PRIVATE(dentry->d_inode))
 		return 0;
 
 	if (list && len <= list_size) {
diff --git a/fs/reiserfs/xattr_user.c b/fs/reiserfs/xattr_user.c
index e3238dc..75d59c4 100644
--- a/fs/reiserfs/xattr_user.c
+++ b/fs/reiserfs/xattr_user.c
@@ -7,34 +7,35 @@
 #include <asm/uaccess.h>
 
 static int
-user_get(struct inode *inode, const char *name, void *buffer, size_t size)
+user_get(struct dentry *dentry, const char *name, void *buffer, size_t size,
+	 int handler_flags)
 {
 
 	if (strlen(name) < sizeof(XATTR_USER_PREFIX))
 		return -EINVAL;
-	if (!reiserfs_xattrs_user(inode->i_sb))
+	if (!reiserfs_xattrs_user(dentry->d_sb))
 		return -EOPNOTSUPP;
-	return reiserfs_xattr_get(inode, name, buffer, size);
+	return reiserfs_xattr_get(dentry->d_inode, name, buffer, size);
 }
 
 static int
-user_set(struct inode *inode, const char *name, const void *buffer,
-	 size_t size, int flags)
+user_set(struct dentry *dentry, const char *name, const void *buffer,
+	 size_t size, int flags, int handler_flags)
 {
 	if (strlen(name) < sizeof(XATTR_USER_PREFIX))
 		return -EINVAL;
 
-	if (!reiserfs_xattrs_user(inode->i_sb))
+	if (!reiserfs_xattrs_user(dentry->d_sb))
 		return -EOPNOTSUPP;
-	return reiserfs_xattr_set(inode, name, buffer, size, flags);
+	return reiserfs_xattr_set(dentry->d_inode, name, buffer, size, flags);
 }
 
-static size_t user_list(struct inode *inode, char *list, size_t list_size,
-			const char *name, size_t name_len)
+static size_t user_list(struct dentry *dentry, char *list, size_t list_size,
+			const char *name, size_t name_len, int handler_flags)
 {
 	const size_t len = name_len + 1;
 
-	if (!reiserfs_xattrs_user(inode->i_sb))
+	if (!reiserfs_xattrs_user(dentry->d_sb))
 		return 0;
 	if (list && len <= list_size) {
 		memcpy(list, name, name_len);