[PATCH 3.15 06/37] nfs: only show Posix ACLs in listxattr if actually present

Greg Kroah-Hartman
2014-07-30T01:48:42Z

From: Christoph Hellwig <hch@lst.de>

commit 74adf83f5d7720925499b4938f930591f947b660 upstream.

The big ACL switched nfs to use generic_listxattr, which calls all existing
->list handlers. Add a custom .listxattr implementation that only lists
the ACLs if they actually are present on the given inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Philippe Troin <phil@fifi.org>
Tested-by: Philippe Troin <phil@fifi.org>
Fixes: 013cdf1088d7 (nfs: use generic posix ACL infrastructure ...)
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/nfs/nfs3acl.c | 43 +++++++++++++++++++++++++++++++++++++++++++
fs/nfs/nfs3proc.c | 4 ++--
2 files changed, 45 insertions(+), 2 deletions(-)

--- a/fs/nfs/nfs3acl.c
+++ b/fs/nfs/nfs3acl.c
@@ -247,3 +247,46 @@ const struct xattr_handler *nfs3_xattr_h
&posix_acl_default_xattr_handler,
NULL,
};
+
+static int
+nfs3_list_one_acl(struct inode *inode, int type, const char *name, void *data,
+ size_t size, ssize_t *result)
+{
+ struct posix_acl *acl;
+ char *p = data + *result;
+
+ acl = get_acl(inode, type);
+ if (!acl)
+ return 0;
+
+ posix_acl_release(acl);
+
+ *result += strlen(name);
+ *result += 1;
+ if (!size)
+ return 0;
+ if (*result > size)
+ return -ERANGE;
+
+ strcpy(p, name);
+ return 0;
+}
+
+ssize_t
+nfs3_listxattr(struct dentry *dentry, char *data, size_t size)
+{
+ struct inode *inode = dentry->d_inode;
+ ssize_t result = 0;
+ int error;
+
+ error = nfs3_list_one_acl(inode, ACL_TYPE_ACCESS,
+ POSIX_ACL_XATTR_ACCESS, data, size, &result);
+ if (error)
+ return error;
+
+ error = nfs3_list_one_acl(inode, ACL_TYPE_DEFAULT,
+ POSIX_ACL_XATTR_DEFAULT, data, size, &result);
+ if (error)
+ return error;
+ return result;
+}
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -891,7 +891,7 @@ static const struct inode_operations nfs
.getattr = nfs_getattr,
.setattr = nfs_setattr,
#ifdef CONFIG_NFS_V3_ACL
- .listxattr = generic_listxattr,
+ .listxattr = nfs3_listxattr,
.getxattr = generic_getxattr,
.setxattr = generic_setxattr,
.removexattr = generic_removexattr,
@@ -905,7 +905,7 @@ static const struct inode_operations nfs
.getattr = nfs_getattr,
.setattr = nfs_setattr,
#ifdef CONFIG_NFS_V3_ACL
- .listxattr = generic_listxattr,
+ .listxattr = nfs3_listxattr,
.getxattr = generic_getxattr,
.setxattr = generic_setxattr,
.removexattr = generic_removexattr,