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

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 <[email protected]> Reported-by: Larry McVoy <[email protected]> Cc: [email protected] Signed-off-by: J. Bruce Fields <[email protected]>
kusora · Oct 17, 2012 · cd0b16c · cd0b16c
1 parent ddffeb8
commit cd0b16c
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Showing 2 changed files with 3 additions and 2 deletions.
diff --git 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
@@ -68,7 +68,8 @@ 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;