NFS: introduce generic decode_getattr function
Getattr should be able to decode errors and the readdir file handle.
decode_getfattr_attrs does the actual attribute decoding, while
decode_getfattr_generic will check the opcode before decoding. This will
let other functions call decode_getfattr_attrs to decode their attributes.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 8346e97..b7eff20 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -2848,6 +2848,58 @@
return -EIO;
}
+static int decode_attr_error(struct xdr_stream *xdr, uint32_t *bitmap)
+{
+ __be32 *p;
+
+ if (unlikely(bitmap[0] & (FATTR4_WORD0_RDATTR_ERROR - 1U)))
+ return -EIO;
+ if (likely(bitmap[0] & FATTR4_WORD0_RDATTR_ERROR)) {
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ goto out_overflow;
+ bitmap[0] &= ~FATTR4_WORD0_RDATTR_ERROR;
+ }
+ return 0;
+out_overflow:
+ print_overflow_msg(__func__, xdr);
+ return -EIO;
+}
+
+static int decode_attr_filehandle(struct xdr_stream *xdr, uint32_t *bitmap, struct nfs_fh *fh)
+{
+ __be32 *p;
+ int len;
+
+ if (fh == NULL) {
+ bitmap[0] &= ~FATTR4_WORD0_FILEHANDLE;
+ return 0;
+ }
+
+ memset(fh, 0, sizeof(*fh));
+
+ if (unlikely(bitmap[0] & (FATTR4_WORD0_FILEHANDLE - 1U)))
+ return -EIO;
+ if (likely(bitmap[0] & FATTR4_WORD0_FILEHANDLE)) {
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ goto out_overflow;
+ len = be32_to_cpup(p);
+ if (len > NFS4_FHSIZE)
+ return -EIO;
+ fh->size = len;
+ p = xdr_inline_decode(xdr, len);
+ if (unlikely(!p))
+ goto out_overflow;
+ memcpy(fh->data, p, len);
+ bitmap[0] &= ~FATTR4_WORD0_FILEHANDLE;
+ }
+ return 0;
+out_overflow:
+ print_overflow_msg(__func__, xdr);
+ return -EIO;
+}
+
static int decode_attr_aclsupport(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
__be32 *p;
@@ -3744,29 +3796,14 @@
return status;
}
-static int decode_getfattr(struct xdr_stream *xdr, struct nfs_fattr *fattr,
+static int decode_getfattr_attrs(struct xdr_stream *xdr, uint32_t *bitmap,
+ struct nfs_fattr *fattr, struct nfs_fh *fh,
const struct nfs_server *server, int may_sleep)
{
- __be32 *savep;
- uint32_t attrlen,
- bitmap[2] = {0},
- type;
int status;
umode_t fmode = 0;
uint64_t fileid;
-
- status = decode_op_hdr(xdr, OP_GETATTR);
- if (status < 0)
- goto xdr_error;
-
- status = decode_attr_bitmap(xdr, bitmap);
- if (status < 0)
- goto xdr_error;
-
- status = decode_attr_length(xdr, &attrlen, &savep);
- if (status < 0)
- goto xdr_error;
-
+ uint32_t type;
status = decode_attr_type(xdr, bitmap, &type);
if (status < 0)
@@ -3792,6 +3829,14 @@
goto xdr_error;
fattr->valid |= status;
+ status = decode_attr_error(xdr, bitmap);
+ if (status < 0)
+ goto xdr_error;
+
+ status = decode_attr_filehandle(xdr, bitmap, fh);
+ if (status < 0)
+ goto xdr_error;
+
status = decode_attr_fileid(xdr, bitmap, &fattr->fileid);
if (status < 0)
goto xdr_error;
@@ -3857,17 +3902,51 @@
status = decode_attr_mounted_on_fileid(xdr, bitmap, &fileid);
if (status < 0)
goto xdr_error;
- if (status != 0 && !(fattr->valid & status)) {
+ if (status != 0) {
fattr->fileid = fileid;
fattr->valid |= status;
}
+xdr_error:
+ dprintk("%s: xdr returned %d\n", __func__, -status);
+ return status;
+}
+
+static int decode_getfattr_generic(struct xdr_stream *xdr, struct nfs_fattr *fattr,
+ struct nfs_fh *fh, const struct nfs_server *server, int may_sleep)
+{
+ __be32 *savep;
+ uint32_t attrlen,
+ bitmap[2] = {0};
+ int status;
+
+ status = decode_op_hdr(xdr, OP_GETATTR);
+ if (status < 0)
+ goto xdr_error;
+
+ status = decode_attr_bitmap(xdr, bitmap);
+ if (status < 0)
+ goto xdr_error;
+
+ status = decode_attr_length(xdr, &attrlen, &savep);
+ if (status < 0)
+ goto xdr_error;
+
+ status = decode_getfattr_attrs(xdr, bitmap, fattr, fh, server, may_sleep);
+ if (status < 0)
+ goto xdr_error;
+
status = verify_attr_len(xdr, savep, attrlen);
xdr_error:
dprintk("%s: xdr returned %d\n", __func__, -status);
return status;
}
+static int decode_getfattr(struct xdr_stream *xdr, struct nfs_fattr *fattr,
+ const struct nfs_server *server, int may_sleep)
+{
+ return decode_getfattr_generic(xdr, fattr, NULL, server, may_sleep);
+}
static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo)
{