linux-kernel - [PATCH 4.19 068/118] nfsd: avoid uninitialized variable warning

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Message-Id: <20190613075647.789649503@linuxfoundation.org>
Date:   Thu, 13 Jun 2019 10:33:26 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Arnd Bergmann <arnd@...db.de>,
        "J. Bruce Fields" <bfields@...hat.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.19 068/118] nfsd: avoid uninitialized variable warning

[ Upstream commit 0ab88ca4bcf18ba21058d8f19220f60afe0d34d8 ]

clang warns that 'contextlen' may be accessed without an initialization:

fs/nfsd/nfs4xdr.c:2911:9: error: variable 'contextlen' is uninitialized when used here [-Werror,-Wuninitialized]
                                                                contextlen);
                                                                ^~~~~~~~~~
fs/nfsd/nfs4xdr.c:2424:16: note: initialize the variable 'contextlen' to silence this warning
        int contextlen;
                      ^
                       = 0

Presumably this cannot happen, as FATTR4_WORD2_SECURITY_LABEL is
set if CONFIG_NFSD_V4_SECURITY_LABEL is enabled.
Adding another #ifdef like the other two in this function
avoids the warning.

Signed-off-by: Arnd Bergmann <arnd@...db.de>
Signed-off-by: J. Bruce Fields <bfields@...hat.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 fs/nfsd/nfs4xdr.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 418fa9c78186..db0beefe65ec 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2413,8 +2413,10 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
 	__be32 status;
 	int err;
 	struct nfs4_acl *acl = NULL;
+#ifdef CONFIG_NFSD_V4_SECURITY_LABEL
 	void *context = NULL;
 	int contextlen;
+#endif
 	bool contextsupport = false;
 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
 	u32 minorversion = resp->cstate.minorversion;
@@ -2899,12 +2901,14 @@ out_acl:
 			*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_TIME_METADATA);
 	}
 
+#ifdef CONFIG_NFSD_V4_SECURITY_LABEL
 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
 		status = nfsd4_encode_security_label(xdr, rqstp, context,
 								contextlen);
 		if (status)
 			goto out;
 	}
+#endif
 
 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
-- 
2.20.1