Re: [PATCH] NFSv4.2: fix return value of _nfs4_get_security_label()

Hi Ondrej,

On Tue, Mar 9, 2021 at 5:10 AM Ondrej Mosnacek [off-list ref] wrote:

On Fri, Jan 15, 2021 at 6:43 PM Ondrej Mosnacek [off-list ref] wrote:

quoted

An xattr 'get' handler is expected to return the length of the value on
success, yet _nfs4_get_security_label() (and consequently also
nfs4_xattr_get_nfs4_label(), which is used as an xattr handler) returns
just 0 on success.

Fix this by returning label.len instead, which contains the length of
the result.

Fixes: aa9c2669626c ("NFS: Client implementation of Labeled-NFS")
Signed-off-by: Ondrej Mosnacek <redacted>
---
 fs/nfs/nfs4proc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 2f4679a62712a..28465d8aada64 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c

@@ -5971,7 +5971,7 @@ static int _nfs4_get_security_label(struct inode *inode, void *buf,
                return ret;
        if (!(fattr.valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL))
                return -ENOENT;
-       return 0;
+       return label.len;
 }

 static int nfs4_get_security_label(struct inode *inode, void *buf,
--

2.29.2

Ping. It's been almost 2 months now, and I can't see the patch applied
anywhere, nor has it received any feedback from the NFS maintainers...
Trond? Anna?

Thanks for the ping! I've queued this up for the next bugfixes pull request.

Anna

--
Ondrej Mosnacek
Software Engineer, Linux Security - SELinux kernel
Red Hat, Inc.