[ 3.5.yuz extended stable ] Patch "NLM: nlm_lookup_file() may return NLMv4-specific error codes" has been added to staging queue

[Herton Ronaldo Krzesinski]

This is a note to let you know that I have just added a patch titled

    NLM: nlm_lookup_file() may return NLMv4-specific error codes

to the linux-3.5.y-queue branch of the 3.5.yuz extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.yuz tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Herton

------

>From 7c559112ea978637c062d67574f3ba4c1fd9c18d Mon Sep 17 00:00:00 2001
From: Trond Myklebust <Trond.Myklebust at netapp.com>
Date: Sat, 13 Oct 2012 00:30:28 -0400
Subject: [PATCH] NLM: nlm_lookup_file() may return NLMv4-specific error codes

commit cd0b16c1c3cda12dbed1f8de8f1a9b0591990724 upstream.

If the filehandle is stale, or open access is denied for some reason,
nlm_fopen() may return one of the NLMv4-specific error codes nlm4_stale_fh
or nlm4_failed. These get passed right through nlm_lookup_file(),
and so when nlmsvc_retrieve_args() calls the latter, it needs to filter
the result through the cast_status() machinery.

Failure to do so, will trigger the BUG_ON() in encode_nlm_stat...

Signed-off-by: Trond Myklebust <Trond.Myklebust at netapp.com>
Reported-by: Larry McVoy <lm at bitmover.com>
Signed-off-by: J. Bruce Fields <bfields at redhat.com>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 fs/lockd/clntxdr.c |    2 +-
 fs/lockd/svcproc.c |    3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/lockd/clntxdr.c b/fs/lockd/clntxdr.c
index d269ada..982d267 100644
--- a/fs/lockd/clntxdr.c
+++ b/fs/lockd/clntxdr.c
@@ -223,7 +223,7 @@ static void encode_nlm_stat(struct xdr_stream *xdr,
 {
 	__be32 *p;

-	BUG_ON(be32_to_cpu(stat) > NLM_LCK_DENIED_GRACE_PERIOD);
+	WARN_ON_ONCE(be32_to_cpu(stat) > NLM_LCK_DENIED_GRACE_PERIOD);
 	p = xdr_reserve_space(xdr, 4);
 	*p = stat;
 }
diff --git a/fs/lockd/svcproc.c b/fs/lockd/svcproc.c
index d27aab1..d413af3 100644
--- a/fs/lockd/svcproc.c
+++ b/fs/lockd/svcproc.c
@@ -67,7 +67,8 @@ nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,

 	/* Obtain file pointer. Not used by FREE_ALL call. */
 	if (filp != NULL) {
-		if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
+		error = cast_status(nlm_lookup_file(rqstp, &file, &lock->fh));
+		if (error != 0)
 			goto no_locks;
 		*filp = file;

--
1.7.9.5