[PATCH v10 42/46] nfs: Fix GETATTR bitmap verification

Andreas Gruenbacher
2015-10-11T23:04:05Z

When decoding GETATTR replies, the client checks the attribute bitmap
for which attributes the server has sent. It misses bits at the word
boundaries, though; fix that.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
---
fs/nfs/nfs4xdr.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)

diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 788adf3..6f6d921 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -4375,6 +4375,11 @@ static int decode_statfs(struct xdr_stream *xdr, struct nfs_fsstat *fsstat)
goto xdr_error;
if ((status = decode_attr_files_total(xdr, bitmap, &fsstat->tfiles)) != 0)
goto xdr_error;
+
+ status = -EIO;
+ if (unlikely(bitmap[0]))
+ goto xdr_error;
+
if ((status = decode_attr_space_avail(xdr, bitmap, &fsstat->abytes)) != 0)
goto xdr_error;
if ((status = decode_attr_space_free(xdr, bitmap, &fsstat->fbytes)) != 0)
@@ -4574,6 +4579,10 @@ static int decode_getfattr_attrs(struct xdr_stream *xdr, uint32_t *bitmap,
goto xdr_error;
fattr->valid |= status;

+ status = -EIO;
+ if (unlikely(bitmap[0]))
+ goto xdr_error;
+
status = decode_attr_mode(xdr, bitmap, &fmode);
if (status < 0)
goto xdr_error;
@@ -4627,6 +4636,10 @@ static int decode_getfattr_attrs(struct xdr_stream *xdr, uint32_t *bitmap,
goto xdr_error;
fattr->valid |= status;

+ status = -EIO;
+ if (unlikely(bitmap[1]))
+ goto xdr_error;
+
status = decode_attr_mdsthreshold(xdr, bitmap, fattr->mdsthreshold);
if (status < 0)
goto xdr_error;
@@ -4789,12 +4802,22 @@ static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo)
if ((status = decode_attr_maxwrite(xdr, bitmap, &fsinfo->wtmax)) != 0)
goto xdr_error;
fsinfo->wtpref = fsinfo->wtmax;
+
+ status = -EIO;
+ if (unlikely(bitmap[0]))
+ goto xdr_error;
+
status = decode_attr_time_delta(xdr, bitmap, &fsinfo->time_delta);
if (status != 0)
goto xdr_error;
status = decode_attr_pnfstype(xdr, bitmap, &fsinfo->layouttype);
if (status != 0)
goto xdr_error;
+
+ status = -EIO;
+ if (unlikely(bitmap[1]))
+ goto xdr_error;
+
status = decode_attr_layout_blksize(xdr, bitmap, &fsinfo->blksize);
if (status)
goto xdr_error;