Merge tag 'nfs-for-5.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Stable fixes:
   - Fix a page leak in nfs_destroy_unlinked_subrequests()

   - Fix use-after-free issues in nfs_pageio_add_request()

   - Fix new mount code constant_table array definitions

   - finish_automount() requires us to hold 2 refs to the mount record

  Features:
   - Improve the accuracy of telldir/seekdir by using 64-bit cookies
     when possible.

   - Allow one RDMA active connection and several zombie connections to
     prevent blocking if the remote server is unresponsive.

   - Limit the size of the NFS access cache by default

   - Reduce the number of references to credentials that are taken by
     NFS

   - pNFS files and flexfiles drivers now support per-layout segment
     COMMIT lists.

   - Enable partial-file layout segments in the pNFS/flexfiles driver.

   - Add support for CB_RECALL_ANY to the pNFS flexfiles layout type

   - pNFS/flexfiles Report NFS4ERR_DELAY and NFS4ERR_GRACE errors from
     the DS using the layouterror mechanism.

  Bugfixes and cleanups:
   - SUNRPC: Fix krb5p regressions

   - Don't specify NFS version in "UDP not supported" error

   - nfsroot: set tcp as the default transport protocol

   - pnfs: Return valid stateids in nfs_layout_find_inode_by_stateid()

   - alloc_nfs_open_context() must use the file cred when available

   - Fix locking when dereferencing the delegation cred

   - Fix memory leaks in O_DIRECT when nfs_get_lock_context() fails

   - Various clean ups of the NFS O_DIRECT commit code

   - Clean up RDMA connect/disconnect

   - Replace zero-length arrays with C99-style flexible arrays"

* tag 'nfs-for-5.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (86 commits)
  NFS: Clean up process of marking inode stale.
  SUNRPC: Don't start a timer on an already queued rpc task
  NFS/pnfs: Reference the layout cred in pnfs_prepare_layoutreturn()
  NFS/pnfs: Fix dereference of layout cred in pnfs_layoutcommit_inode()
  NFS: Beware when dereferencing the delegation cred
  NFS: Add a module parameter to set nfs_mountpoint_expiry_timeout
  NFS: finish_automount() requires us to hold 2 refs to the mount record
  NFS: Fix a few constant_table array definitions
  NFS: Try to join page groups before an O_DIRECT retransmission
  NFS: Refactor nfs_lock_and_join_requests()
  NFS: Reverse the submission order of requests in __nfs_pageio_add_request()
  NFS: Clean up nfs_lock_and_join_requests()
  NFS: Remove the redundant function nfs_pgio_has_mirroring()
  NFS: Fix memory leaks in nfs_pageio_stop_mirroring()
  NFS: Fix a request reference leak in nfs_direct_write_clear_reqs()
  NFS: Fix use-after-free issues in nfs_pageio_add_request()
  NFS: Fix races nfs_page_group_destroy() vs nfs_destroy_unlinked_subrequests()
  NFS: Fix a page leak in nfs_destroy_unlinked_subrequests()
  NFS: Remove unused FLUSH_SYNC support in nfs_initiate_pgio()
  pNFS/flexfiles: Specify the layout segment range in LAYOUTGET
  ...

1 files changed, 68 insertions, 26 deletions

diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index ee060d57d216..25fbd8d9de74 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -20,6 +20,7 @@
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/auth.h>
 #include <linux/sunrpc/auth_gss.h>
+#include <linux/sunrpc/gss_krb5.h>
 #include <linux/sunrpc/svcauth_gss.h>
 #include <linux/sunrpc/gss_err.h>
 #include <linux/workqueue.h>
@@ -1050,7 +1051,7 @@ gss_create_new(const struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
 		goto err_put_mech;
 	auth = &gss_auth->rpc_auth;
 	auth->au_cslack = GSS_CRED_SLACK >> 2;
-	auth->au_rslack = GSS_VERF_SLACK >> 2;
+	auth->au_rslack = GSS_KRB5_MAX_SLACK_NEEDED >> 2;
 	auth->au_verfsize = GSS_VERF_SLACK >> 2;
 	auth->au_ralign = GSS_VERF_SLACK >> 2;
 	auth->au_flags = 0;
@@ -1724,8 +1725,9 @@ bad_mic:
 	goto out;
 }
 
-static int gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
-			      struct rpc_task *task, struct xdr_stream *xdr)
+static noinline_for_stack int
+gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
+		   struct rpc_task *task, struct xdr_stream *xdr)
 {
 	struct rpc_rqst *rqstp = task->tk_rqstp;
 	struct xdr_buf integ_buf, *snd_buf = &rqstp->rq_snd_buf;
@@ -1816,8 +1818,9 @@ out:
 	return -EAGAIN;
 }
 
-static int gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
-			     struct rpc_task *task, struct xdr_stream *xdr)
+static noinline_for_stack int
+gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
+		  struct rpc_task *task, struct xdr_stream *xdr)
 {
 	struct rpc_rqst *rqstp = task->tk_rqstp;
 	struct xdr_buf	*snd_buf = &rqstp->rq_snd_buf;
@@ -1934,35 +1937,69 @@ gss_unwrap_resp_auth(struct rpc_cred *cred)
 	return 0;
 }
 
-static int
+/*
+ * RFC 2203, Section 5.3.2.2
+ *
+ *	struct rpc_gss_integ_data {
+ *		opaque databody_integ<>;
+ *		opaque checksum<>;
+ *	};
+ *
+ *	struct rpc_gss_data_t {
+ *		unsigned int seq_num;
+ *		proc_req_arg_t arg;
+ *	};
+ */
+static noinline_for_stack int
 gss_unwrap_resp_integ(struct rpc_task *task, struct rpc_cred *cred,
 		      struct gss_cl_ctx *ctx, struct rpc_rqst *rqstp,
 		      struct xdr_stream *xdr)
 {
-	struct xdr_buf integ_buf, *rcv_buf = &rqstp->rq_rcv_buf;
-	u32 data_offset, mic_offset, integ_len, maj_stat;
+	struct xdr_buf gss_data, *rcv_buf = &rqstp->rq_rcv_buf;
 	struct rpc_auth *auth = cred->cr_auth;
+	u32 len, offset, seqno, maj_stat;
 	struct xdr_netobj mic;
-	__be32 *p;
+	int ret;
 
-	p = xdr_inline_decode(xdr, 2 * sizeof(*p));
-	if (unlikely(!p))
+	ret = -EIO;
+	mic.data = NULL;
+
+	/* opaque databody_integ<>; */
+	if (xdr_stream_decode_u32(xdr, &len))
 		goto unwrap_failed;
-	integ_len = be32_to_cpup(p++);
-	if (integ_len & 3)
+	if (len & 3)
 		goto unwrap_failed;
-	data_offset = (u8 *)(p) - (u8 *)rcv_buf->head[0].iov_base;
-	mic_offset = integ_len + data_offset;
-	if (mic_offset > rcv_buf->len)
+	offset = rcv_buf->len - xdr_stream_remaining(xdr);
+	if (xdr_stream_decode_u32(xdr, &seqno))
 		goto unwrap_failed;
-	if (be32_to_cpup(p) != rqstp->rq_seqno)
+	if (seqno != rqstp->rq_seqno)
 		goto bad_seqno;
+	if (xdr_buf_subsegment(rcv_buf, &gss_data, offset, len))
+		goto unwrap_failed;
 
-	if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset, integ_len))
+	/*
+	 * The xdr_stream now points to the beginning of the
+	 * upper layer payload, to be passed below to
+	 * rpcauth_unwrap_resp_decode(). The checksum, which
+	 * follows the upper layer payload in @rcv_buf, is
+	 * located and parsed without updating the xdr_stream.
+	 */
+
+	/* opaque checksum<>; */
+	offset += len;
+	if (xdr_decode_word(rcv_buf, offset, &len))
+		goto unwrap_failed;
+	offset += sizeof(__be32);
+	if (offset + len > rcv_buf->len)
 		goto unwrap_failed;
-	if (xdr_buf_read_mic(rcv_buf, &mic, mic_offset))
+	mic.len = len;
+	mic.data = kmalloc(len, GFP_NOFS);
+	if (!mic.data)
+		goto unwrap_failed;
+	if (read_bytes_from_xdr_buf(rcv_buf, offset, mic.data, mic.len))
 		goto unwrap_failed;
-	maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
+
+	maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &gss_data, &mic);
 	if (maj_stat == GSS_S_CONTEXT_EXPIRED)
 		clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 	if (maj_stat != GSS_S_COMPLETE)
@@ -1970,19 +2007,24 @@ gss_unwrap_resp_integ(struct rpc_task *task, struct rpc_cred *cred,
 
 	auth->au_rslack = auth->au_verfsize + 2 + 1 + XDR_QUADLEN(mic.len);
 	auth->au_ralign = auth->au_verfsize + 2;
-	return 0;
+	ret = 0;
+
+out:
+	kfree(mic.data);
+	return ret;
+
 unwrap_failed:
 	trace_rpcgss_unwrap_failed(task);
-	return -EIO;
+	goto out;
 bad_seqno:
-	trace_rpcgss_bad_seqno(task, rqstp->rq_seqno, be32_to_cpup(p));
-	return -EIO;
+	trace_rpcgss_bad_seqno(task, rqstp->rq_seqno, seqno);
+	goto out;
 bad_mic:
 	trace_rpcgss_verify_mic(task, maj_stat);
-	return -EIO;
+	goto out;
 }
 
-static int
+static noinline_for_stack int
 gss_unwrap_resp_priv(struct rpc_task *task, struct rpc_cred *cred,
 		     struct gss_cl_ctx *ctx, struct rpc_rqst *rqstp,
 		     struct xdr_stream *xdr)