[PATCH] fs: nfs: Added pointer check

[Denis Arefev]

Return value of a function 'xdr_inline_decode' is dereferenced at
nfs4xdr.c:5540 without checking for null,
ut it is usually checked for this function

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Denis Arefev <arefev@xxxxxxxxx>
---
 fs/nfs/nfs4xdr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index c6dbfcae7517..571cc63ecb61 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -5533,6 +5533,8 @@ static int decode_op_map(struct xdr_stream *xdr, struct nfs4_op_map *op_map)
 	if (bitmap_words > NFS4_OP_MAP_NUM_WORDS)
 		return -EIO;
 	p = xdr_inline_decode(xdr, 4 * bitmap_words);
+	if (!p)
+		return -EIO;
 	for (i = 0; i < bitmap_words; i++)
 		op_map->u.words[i] = be32_to_cpup(p++);
 
-- 
2.25.1