2017-05-05 04:00:00

by Jianhong.Yin

[permalink] [raw]
Subject: [PATCH] fs/nfs: fix covscan error: FORWARD_NULL

'''
Error: FORWARD_NULL (CWE-476): [#def3702]
.../fs/nfs/nfs4xdr.c:1085: var_compare_op: Comparing "label" to null implies that "label" might be null.
.../fs/nfs/nfs4xdr.c:1129: var_deref_op: Dereferencing null pointer "label".
1127| }
1128| if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
1129|-> *p++ = cpu_to_be32(label->lfs);
1130| *p++ = cpu_to_be32(label->pi);
1131| *p++ = cpu_to_be32(label->len);

Error: FORWARD_NULL (CWE-476): [#def3703]
.../fs/nfs/nfs4xdr.c:1027: var_compare_op: Comparing "umask" to null implies that "umask" might be null.
.../fs/nfs/nfs4xdr.c:1136: var_deref_op: Dereferencing null pointer "umask".
1134| if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
1135| *p++ = cpu_to_be32(iap->ia_mode & S_IALLUGO);
1136|-> *p++ = cpu_to_be32(*umask);
1137| }
'''

Signed-off-by: Jianhong Yin <[email protected]>
---
fs/nfs/nfs4xdr.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 80ce289..a86ed66 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -1124,7 +1124,7 @@ static void encode_attrs(struct xdr_stream *xdr, const struct iattr *iap,
} else
*p++ = cpu_to_be32(NFS4_SET_TO_SERVER_TIME);
}
- if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
+ if (label && bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
*p++ = cpu_to_be32(label->lfs);
*p++ = cpu_to_be32(label->pi);
*p++ = cpu_to_be32(label->len);
@@ -1132,7 +1132,8 @@ static void encode_attrs(struct xdr_stream *xdr, const struct iattr *iap,
}
if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
*p++ = cpu_to_be32(iap->ia_mode & S_IALLUGO);
- *p++ = cpu_to_be32(*umask);
+ if (umask != NULL)
+ *p++ = cpu_to_be32(*umask);
}

/* out: */
--
1.8.3.1