diff options
Diffstat (limited to 'fs/nfs/nfs4xdr.c')
| -rw-r--r-- | fs/nfs/nfs4xdr.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 33bd8d0f745..94da8675b89 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -4975,11 +4975,19 @@ static int decode_getacl(struct xdr_stream *xdr, struct rpc_rqst *req, bitmap[3] = {0}; struct kvec *iov = req->rq_rcv_buf.head; int status; + size_t page_len = xdr->buf->page_len; res->acl_len = 0; if ((status = decode_op_hdr(xdr, OP_GETATTR)) != 0) goto out; + bm_p = xdr->p; + res->acl_data_offset = be32_to_cpup(bm_p) + 2; + res->acl_data_offset <<= 2; + /* Check if the acl data starts beyond the allocated buffer */ + if (res->acl_data_offset > page_len) + return -ERANGE; + if ((status = decode_attr_bitmap(xdr, bitmap)) != 0) goto out; if ((status = decode_attr_length(xdr, &attrlen, &savep)) != 0) @@ -4989,28 +4997,24 @@ static int decode_getacl(struct xdr_stream *xdr, struct rpc_rqst *req, return -EIO; if (likely(bitmap[0] & FATTR4_WORD0_ACL)) { size_t hdrlen; - u32 recvd; /* The bitmap (xdr len + bitmaps) and the attr xdr len words * are stored with the acl data to handle the problem of * variable length bitmaps.*/ xdr->p = bm_p; - res->acl_data_offset = be32_to_cpup(bm_p) + 2; - res->acl_data_offset <<= 2; /* We ignore &savep and don't do consistency checks on * the attr length. Let userspace figure it out.... */ hdrlen = (u8 *)xdr->p - (u8 *)iov->iov_base; attrlen += res->acl_data_offset; - recvd = req->rq_rcv_buf.len - hdrlen; - if (attrlen > recvd) { + if (attrlen > page_len) { if (res->acl_flags & NFS4_ACL_LEN_REQUEST) { /* getxattr interface called with a NULL buf */ res->acl_len = attrlen; goto out; } - dprintk("NFS: acl reply: attrlen %u > recvd %u\n", - attrlen, recvd); + dprintk("NFS: acl reply: attrlen %u > page_len %zu\n", + attrlen, page_len); return -EINVAL; } xdr_read_pages(xdr, attrlen); |