Commit 6ac79291 authored by Long Li's avatar Long Li Committed by Steve French
Browse files

CIFS: Avoid returning EBUSY to upper layer VFS 



EBUSY is not handled by VFS, and will be passed to user-mode. This is not
correct as we need to wait for more credits.

This patch also fixes a bug where rsize or wsize is used uninitialized when
the call to server->ops->wait_mtu_credits() fails.

Reported-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: default avatarLong Li <longli@microsoft.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
Reviewed-by: default avatarPavel Shilovsky <pshilov@microsoft.com>
parent c988de29

fs/cifs/file.c

+6 −25
Original line number Diff line number Diff line
@@ -2541,14 +2541,13 @@ static int 
cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list,

	struct cifs_aio_ctx *ctx)

{

	int wait_retry = 0;

	unsigned int wsize, credits;

	int rc;

	struct TCP_Server_Info *server =

		tlink_tcon(wdata->cfile->tlink)->ses->server;



	/*

	 * Try to resend this wdata, waiting for credits up to 3 seconds.

	 * Wait for credits to resend this wdata.

	 * Note: we are attempting to resend the whole wdata not in segments

	 */

	do {
@@ -2556,19 +2555,13 @@ cifs_resend_wdata(struct cifs_writedata *wdata, struct list_head *wdata_list, 
			server, wdata->bytes, &wsize, &credits);



		if (rc)

			break;

			goto out;



		if (wsize < wdata->bytes) {

			add_credits_and_wake_if(server, credits, 0);

			msleep(1000);

			wait_retry++;

		}

	} while (wsize < wdata->bytes && wait_retry < 3);



	if (wsize < wdata->bytes) {

		rc = -EBUSY;

		goto out;

		}

	} while (wsize < wdata->bytes);



	rc = -EAGAIN;

	while (rc == -EAGAIN) {
@@ -3234,14 +3227,13 @@ static int cifs_resend_rdata(struct cifs_readdata *rdata, 
			struct list_head *rdata_list,

			struct cifs_aio_ctx *ctx)

{

	int wait_retry = 0;

	unsigned int rsize, credits;

	int rc;

	struct TCP_Server_Info *server =

		tlink_tcon(rdata->cfile->tlink)->ses->server;



	/*

	 * Try to resend this rdata, waiting for credits up to 3 seconds.

	 * Wait for credits to resend this rdata.

	 * Note: we are attempting to resend the whole rdata not in segments

	 */

	do {
@@ -3249,24 +3241,13 @@ static int cifs_resend_rdata(struct cifs_readdata *rdata, 
						&rsize, &credits);



		if (rc)

			break;

			goto out;



		if (rsize < rdata->bytes) {

			add_credits_and_wake_if(server, credits, 0);

			msleep(1000);

			wait_retry++;

		}

	} while (rsize < rdata->bytes && wait_retry < 3);



	/*

	 * If we can't find enough credits to send this rdata

	 * release the rdata and return failure, this will pass

	 * whatever I/O amount we have finished to VFS.

	 */

	if (rsize < rdata->bytes) {

		rc = -EBUSY;

		goto out;

		}

	} while (rsize < rdata->bytes);



	rc = -EAGAIN;

	while (rc == -EAGAIN) {

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