Commit d28d5762 authored by Manu Abraham's avatar Manu Abraham Committed by Linus Torvalds
Browse files

[PATCH] dvb: dst: protect the read/write commands with a mutex 



We need to protect the read/write commands with a mutex.

Bug reported by Henrik Sjoberg <henke@epact.se>

Signed-off-by: default avatarManu Abraham <manu@linuxtv.org>
Signed-off-by: default avatarMichael Krufky <mkrufky@linuxtv.org>
Cc: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 2cbeddc9

drivers/media/dvb/bt8xx/dst.c

+21 −13
Original line number Diff line number Diff line
@@ -910,6 +910,7 @@ static int dst_get_device_id(struct dst_state *state) 


static int dst_probe(struct dst_state *state)

{

	sema_init(&state->dst_mutex, 1);

	if ((rdc_8820_reset(state)) < 0) {

		dprintk(verbose, DST_ERROR, 1, "RDC 8820 RESET Failed.");

		return -1;
@@ -960,21 +961,23 @@ static int dst_probe(struct dst_state *state) 
int dst_command(struct dst_state *state, u8 *data, u8 len)

{

	u8 reply;



	down(&state->dst_mutex);

	if ((dst_comm_init(state)) < 0) {

		dprintk(verbose, DST_NOTICE, 1, "DST Communication Initialization Failed.");

		return -1;

		goto error;

	}

	if (write_dst(state, data, len)) {

		dprintk(verbose, DST_INFO, 1, "Tring to recover.. ");

		if ((dst_error_recovery(state)) < 0) {

			dprintk(verbose, DST_ERROR, 1, "Recovery Failed.");

			return -1;

			goto error;

		}

		return -1;

		goto error;

	}

	if ((dst_pio_disable(state)) < 0) {

		dprintk(verbose, DST_ERROR, 1, "PIO Disable Failed.");

		return -1;

		goto error;

	}

	if (state->type_flags & DST_TYPE_HAS_FW_1)

		udelay(3000);
@@ -982,36 +985,41 @@ int dst_command(struct dst_state *state, u8 *data, u8 len) 
		dprintk(verbose, DST_DEBUG, 1, "Trying to recover.. ");

		if ((dst_error_recovery(state)) < 0) {

			dprintk(verbose, DST_INFO, 1, "Recovery Failed.");

			return -1;

			goto error;

		}

		return -1;

		goto error;

	}

	if (reply != ACK) {

		dprintk(verbose, DST_INFO, 1, "write not acknowledged 0x%02x ", reply);

		return -1;

		goto error;

	}

	if (len >= 2 && data[0] == 0 && (data[1] == 1 || data[1] == 3))

		return 0;

		goto error;

	if (state->type_flags & DST_TYPE_HAS_FW_1)

		udelay(3000);

	else

		udelay(2000);

	if (!dst_wait_dst_ready(state, NO_DELAY))

		return -1;

		goto error;

	if (read_dst(state, state->rxbuffer, FIXED_COMM)) {

		dprintk(verbose, DST_DEBUG, 1, "Trying to recover.. ");

		if ((dst_error_recovery(state)) < 0) {

			dprintk(verbose, DST_INFO, 1, "Recovery failed.");

			return -1;

			goto error;

		}

		return -1;

		goto error;

	}

	if (state->rxbuffer[7] != dst_check_sum(state->rxbuffer, 7)) {

		dprintk(verbose, DST_INFO, 1, "checksum failure");

		return -1;

		goto error;

	}



	up(&state->dst_mutex);

	return 0;



error:

	up(&state->dst_mutex);

	return -EIO;



}

EXPORT_SYMBOL(dst_command);

drivers/media/dvb/bt8xx/dst_ca.c

+11 −6
Original line number Diff line number Diff line
@@ -81,36 +81,41 @@ static int dst_ci_command(struct dst_state* state, u8 * data, u8 *ca_string, u8 
{

	u8 reply;



	down(&state->dst_mutex);

	dst_comm_init(state);

	msleep(65);



	if (write_dst(state, data, len)) {

		dprintk(verbose, DST_CA_INFO, 1, " Write not successful, trying to recover");

		dst_error_recovery(state);

		return -1;

		goto error;

	}

	if ((dst_pio_disable(state)) < 0) {

		dprintk(verbose, DST_CA_ERROR, 1, " DST PIO disable failed.");

		return -1;

		goto error;

	}

	if (read_dst(state, &reply, GET_ACK) < 0) {

		dprintk(verbose, DST_CA_INFO, 1, " Read not successful, trying to recover");

		dst_error_recovery(state);

		return -1;

		goto error;

	}

	if (read) {

		if (! dst_wait_dst_ready(state, LONG_DELAY)) {

			dprintk(verbose, DST_CA_NOTICE, 1, " 8820 not ready");

			return -1;

			goto error;

		}

		if (read_dst(state, ca_string, 128) < 0) {	/*	Try to make this dynamic	*/

			dprintk(verbose, DST_CA_INFO, 1, " Read not successful, trying to recover");

			dst_error_recovery(state);

			return -1;

			goto error;

		}

	}



	up(&state->dst_mutex);

	return 0;



error:

	up(&state->dst_mutex);

	return -EIO;

}

drivers/media/dvb/bt8xx/dst_common.h

+3 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ 
#ifndef DST_COMMON_H

#define DST_COMMON_H



#include <linux/smp_lock.h>

#include <linux/dvb/frontend.h>

#include <linux/device.h>

#include "bt878.h"
@@ -119,6 +120,8 @@ struct dst_state { 
	u8 card_info[8];

	u8 vendor[8];

	u8 board_info[8];



	struct semaphore dst_mutex;

};



struct dst_types {