Commit 0f1db7de authored by Al Viro's avatar Al Viro
Browse files

9p: cope with bogus responses from server in p9_client_{read,write} 

if server claims to have written/read more than we'd told it to,
warn and cap the claimed byte count to avoid advancing more than
we are ready to.
parent 67e808fb

net/9p/client.c

+8 −0
Original line number Diff line number Diff line
@@ -1583,6 +1583,10 @@ p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err) 
			p9_free_req(clnt, req);

			break;

		}

		if (rsize < count) {

			pr_err("bogus RREAD count (%d > %d)\n", count, rsize);

			count = rsize;

		}



		p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);

		if (!count) {
@@ -1650,6 +1654,10 @@ p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err) 
			p9_free_req(clnt, req);

			break;

		}

		if (rsize < count) {

			pr_err("bogus RWRITE count (%d > %d)\n", count, rsize);

			count = rsize;

		}



		p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);