[media] au8522: Avoid memory leak for device config data
authorMauro Carvalho Chehab <mchehab@osg.samsung.com>
Mon, 21 Dec 2015 16:38:31 +0000 (14:38 -0200)
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>
Mon, 21 Dec 2015 19:39:32 +0000 (17:39 -0200)
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>
drivers/media/dvb-frontends/au8522_common.c
drivers/media/dvb-frontends/au8522_decoder.c
drivers/media/dvb-frontends/au8522_dig.c
drivers/media/dvb-frontends/au8522_priv.h

index 3559ff230045450ad885bf8e118aaa27a80c50df..f135126bc373ed1e8e7ad161e40b4fcec16ab0bf 100644 (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 */
index 28d7dc2fee34e94bb3fbb0db4e05e1bc9934cd9e..c8f13d8370e507979bcc2d552aec637b0eed16b4 100644 (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;
        }
 
index f956f13fb3dc04b4f9458e8a6bc8b06f8f5dde5c..6c1e97640f3f6519dbb4689adf578488483803d3 100644 (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;
 
index 951b3847e6f66a95775118a96bf3c4279bb528ef..ee330c61aa613e6792071b0fbd8144e565e4f18a 100644 (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;