From: J. Bruce Fields <bfields@redhat.com>
Date: Thu, 28 Jan 2021 22:36:38 +0000 (-0500)
Subject: nfs: we don't support removing system.nfs4_acl
X-Git-Tag: howlett/maple/20220722_2~3572^2
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=4f8be1f53bf615102d103c0509ffa9596f65b718;p=users%2Fjedix%2Flinux-maple.git

nfs: we don't support removing system.nfs4_acl

The NFSv4 protocol doesn't have any notion of reomoving an attribute, so
removexattr(path,"system.nfs4_acl") doesn't make sense.

There's no documented return value.  Arguably it could be EOPNOTSUPP but
I'm a little worried an application might take that to mean that we
don't support ACLs or xattrs.  How about EINVAL?

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 1002c4f66f3f..c65c4b41e2c1 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5889,6 +5889,9 @@ static int __nfs4_proc_set_acl(struct inode *inode, const void *buf, size_t bufl
 	unsigned int npages = DIV_ROUND_UP(buflen, PAGE_SIZE);
 	int ret, i;
 
+	/* You can't remove system.nfs4_acl: */
+	if (buflen == 0)
+		return -EINVAL;
 	if (!nfs4_server_supports_acls(server))
 		return -EOPNOTSUPP;
 	if (npages > ARRAY_SIZE(pages))