[media] au8522: Avoid memory leak for device config data

As reported by kmemleak:

	unreferenced object 0xffff880321e1da40 (size 32):
	  comm "modprobe", pid 3309, jiffies 4295019569 (age 2359.636s)
	  hex dump (first 32 bytes):
	    47 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  G...............
	    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
	  backtrace:
	    [<ffffffff82278c8e>] kmemleak_alloc+0x4e/0xb0
	    [<ffffffff8153c08c>] kmem_cache_alloc_trace+0x1ec/0x280
	    [<ffffffffa13a896a>] au8522_probe+0x19a/0xa30 [au8522_decoder]
	    [<ffffffff81de0032>] i2c_device_probe+0x2b2/0x490
	    [<ffffffff81ca7004>] driver_probe_device+0x454/0xd90
	    [<ffffffff81ca7c1b>] __device_attach_driver+0x17b/0x230
	    [<ffffffff81ca15da>] bus_for_each_drv+0x11a/0x1b0
	    [<ffffffff81ca6a4d>] __device_attach+0x1cd/0x2c0
	    [<ffffffff81ca7d43>] device_initial_probe+0x13/0x20
	    [<ffffffff81ca451f>] bus_probe_device+0x1af/0x250
	    [<ffffffff81c9e0f3>] device_add+0x943/0x13b0
	    [<ffffffff81c9eb7a>] device_register+0x1a/0x20
	    [<ffffffff81de8626>] i2c_new_device+0x5d6/0x8f0
	    [<ffffffffa0d88ea4>] v4l2_i2c_new_subdev_board+0x1e4/0x250 [v4l2_common]
	    [<ffffffffa0d88fe7>] v4l2_i2c_new_subdev+0xd7/0x110 [v4l2_common]
	    [<ffffffffa13b2f76>] au0828_card_analog_fe_setup+0x2e6/0x3f0 [au0828]

Checking where the error happens:
	(gdb) list *au8522_probe+0x19a
	0x99a is in au8522_probe (drivers/media/dvb-frontends/au8522_decoder.c:761).
	756			printk(KERN_INFO "au8522_decoder attach existing instance.\n");
	757			break;
	758		}
	759
	760		demod_config = kzalloc(sizeof(struct au8522_config), GFP_KERNEL);
	761		if (demod_config == NULL) {
	762			if (instance == 1)
	763				kfree(state);
	764			return -ENOMEM;
	765		}

Shows that the error path is not being handled properly.

The are actually several issues here:

1) config free should have been calling hybrid_tuner_release_state()
function, by calling au8522_release_state();

2) config is only allocated at the digital part. On the analog one,
it is received from the caller.

A complex logic could be added to address it, however, it is simpler
to just embeed config inside the state.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
This commit is contained in:
Mauro Carvalho Chehab 2015-12-21 14:38:31 -02:00
parent c77adf214b
commit aa37763fa4
4 changed files with 16 additions and 26 deletions

View File

@ -44,7 +44,7 @@ int au8522_writereg(struct au8522_state *state, u16 reg, u8 data)
int ret;
u8 buf[] = { (reg >> 8) | 0x80, reg & 0xff, data };
struct i2c_msg msg = { .addr = state->config->demod_address,
struct i2c_msg msg = { .addr = state->config.demod_address,
.flags = 0, .buf = buf, .len = 3 };
ret = i2c_transfer(state->i2c, &msg, 1);
@ -64,9 +64,9 @@ u8 au8522_readreg(struct au8522_state *state, u16 reg)
u8 b1[] = { 0 };
struct i2c_msg msg[] = {
{ .addr = state->config->demod_address, .flags = 0,
{ .addr = state->config.demod_address, .flags = 0,
.buf = b0, .len = 2 },
{ .addr = state->config->demod_address, .flags = I2C_M_RD,
{ .addr = state->config.demod_address, .flags = I2C_M_RD,
.buf = b1, .len = 1 } };
ret = i2c_transfer(state->i2c, msg, 2);
@ -140,7 +140,7 @@ EXPORT_SYMBOL(au8522_release_state);
static int au8522_led_gpio_enable(struct au8522_state *state, int onoff)
{
struct au8522_led_config *led_config = state->config->led_cfg;
struct au8522_led_config *led_config = state->config.led_cfg;
u8 val;
/* bail out if we can't control an LED */
@ -170,7 +170,7 @@ static int au8522_led_gpio_enable(struct au8522_state *state, int onoff)
*/
int au8522_led_ctrl(struct au8522_state *state, int led)
{
struct au8522_led_config *led_config = state->config->led_cfg;
struct au8522_led_config *led_config = state->config.led_cfg;
int i, ret = 0;
/* bail out if we can't control an LED */

View File

@ -730,7 +730,6 @@ static int au8522_probe(struct i2c_client *client,
struct v4l2_ctrl_handler *hdl;
struct v4l2_subdev *sd;
int instance;
struct au8522_config *demod_config;
/* Check if the adapter supports the needed features */
if (!i2c_check_functionality(client->adapter,
@ -754,15 +753,7 @@ static int au8522_probe(struct i2c_client *client,
break;
}
demod_config = kzalloc(sizeof(struct au8522_config), GFP_KERNEL);
if (demod_config == NULL) {
if (instance == 1)
kfree(state);
return -ENOMEM;
}
demod_config->demod_address = 0x8e >> 1;
state->config = demod_config;
state->config.demod_address = 0x8e >> 1;
state->i2c = client->adapter;
sd = &state->sd;
@ -784,8 +775,7 @@ static int au8522_probe(struct i2c_client *client,
int err = hdl->error;
v4l2_ctrl_handler_free(hdl);
kfree(demod_config);
kfree(state);
au8522_release_state(state);
return err;
}

View File

@ -566,7 +566,7 @@ static int au8522_enable_modulation(struct dvb_frontend *fe,
au8522_writereg(state,
VSB_mod_tab[i].reg,
VSB_mod_tab[i].data);
au8522_set_if(fe, state->config->vsb_if);
au8522_set_if(fe, state->config.vsb_if);
break;
case QAM_64:
dprintk("%s() QAM 64\n", __func__);
@ -574,7 +574,7 @@ static int au8522_enable_modulation(struct dvb_frontend *fe,
au8522_writereg(state,
QAM64_mod_tab[i].reg,
QAM64_mod_tab[i].data);
au8522_set_if(fe, state->config->qam_if);
au8522_set_if(fe, state->config.qam_if);
break;
case QAM_256:
if (zv_mode) {
@ -583,7 +583,7 @@ static int au8522_enable_modulation(struct dvb_frontend *fe,
au8522_writereg(state,
QAM256_mod_tab_zv_mode[i].reg,
QAM256_mod_tab_zv_mode[i].data);
au8522_set_if(fe, state->config->qam_if);
au8522_set_if(fe, state->config.qam_if);
msleep(100);
au8522_writereg(state, 0x821a, 0x00);
} else {
@ -592,7 +592,7 @@ static int au8522_enable_modulation(struct dvb_frontend *fe,
au8522_writereg(state,
QAM256_mod_tab[i].reg,
QAM256_mod_tab[i].data);
au8522_set_if(fe, state->config->qam_if);
au8522_set_if(fe, state->config.qam_if);
}
break;
default:
@ -666,7 +666,7 @@ static int au8522_read_status(struct dvb_frontend *fe, enum fe_status *status)
*status |= FE_HAS_LOCK | FE_HAS_SYNC;
}
switch (state->config->status_mode) {
switch (state->config.status_mode) {
case AU8522_DEMODLOCKING:
dprintk("%s() DEMODLOCKING\n", __func__);
if (*status & FE_HAS_VITERBI)
@ -704,7 +704,7 @@ static int au8522_read_status(struct dvb_frontend *fe, enum fe_status *status)
static int au8522_led_status(struct au8522_state *state, const u16 *snr)
{
struct au8522_led_config *led_config = state->config->led_cfg;
struct au8522_led_config *led_config = state->config.led_cfg;
int led;
u16 strong;
@ -758,7 +758,7 @@ static int au8522_read_snr(struct dvb_frontend *fe, u16 *snr)
au8522_readreg(state, 0x4311),
snr);
if (state->config->led_cfg)
if (state->config.led_cfg)
au8522_led_status(state, snr);
return ret;
@ -866,7 +866,7 @@ struct dvb_frontend *au8522_attach(const struct au8522_config *config,
}
/* setup the state */
state->config = config;
state->config = *config;
state->i2c = i2c;
state->operational_mode = AU8522_DIGITAL_MODE;

View File

@ -50,7 +50,7 @@ struct au8522_state {
struct list_head hybrid_tuner_instance_list;
/* configuration settings */
const struct au8522_config *config;
struct au8522_config config;
struct dvb_frontend frontend;