The host_node pointer was assigned and freed in adv7533_parse_dt(), and
later, adv7533_attach_dsi() used the same. Fix this use-after-free issue
with the below changes:
1. Drop host_node from struct adv7511 and instead use a local pointer in
adv7511_probe().
2. Update adv7533_parse_dt() to return the host_node.
3. Pass the host_node as a parameter to adv7533_attach_dsi().
4. Call of_node_put() after use.
Fixes: 1e4d58cd7f88 ("drm/bridge: adv7533: Create a MIPI DSI device")
Cc: sta...@vger.kernel.org
Signed-off-by: Biju Das <biju.das...@bp.renesas.com>
---
Changes in v4:
- Updated commit description.
- Dropped host_node from struct adv7511 and instead used a local pointer
in probe(). Also freeing of host_node pointer after use is done in
probe().
Changes in v3:
- Replace __free construct with readable of_node_put().
Changes in v2:
- Added the tag "Cc: sta...@vger.kernel.org" in the sign-off area.
- Dropped Archit Taneja invalid Mail address
---
drivers/gpu/drm/bridge/adv7511/adv7511.h | 6 +++---
drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 22 ++++++++++++++------
drivers/gpu/drm/bridge/adv7511/adv7533.c | 20 +++++++++---------
3 files changed, 29 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h
b/drivers/gpu/drm/bridge/adv7511/adv7511.h
index ec0b7f3d889c..9f3fae7cc597 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511.h
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511.h
@@ -383,7 +383,6 @@ struct adv7511 {
struct regulator_bulk_data *supplies;
/* ADV7533 DSI RX related params */
- struct device_node *host_node;
struct mipi_dsi_device *dsi;
u8 num_dsi_lanes;
bool use_timing_gen;
@@ -417,8 +416,9 @@ enum drm_mode_status adv7533_mode_valid(struct adv7511 *adv,
const struct drm_display_mode *mode);
int adv7533_patch_registers(struct adv7511 *adv);
int adv7533_patch_cec_registers(struct adv7511 *adv);
-int adv7533_attach_dsi(struct adv7511 *adv);
-int adv7533_parse_dt(struct device_node *np, struct adv7511 *adv);
+int adv7533_attach_dsi(struct adv7511 *adv, struct device_node *host_node);
+struct device_node *adv7533_parse_dt(struct device_node *np,
+ struct adv7511 *adv);
#ifdef CONFIG_DRM_I2C_ADV7511_AUDIO
int adv7511_audio_init(struct device *dev, struct adv7511 *adv7511);
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index eb5919b38263..3f1f309791a5 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -1209,6 +1209,7 @@ static int adv7511_parse_dt(struct device_node *np,
static int adv7511_probe(struct i2c_client *i2c)
{
struct adv7511_link_config link_config;
+ struct device_node *host_node = NULL;
struct adv7511 *adv7511;
struct device *dev = &i2c->dev;
unsigned int val;
@@ -1233,12 +1234,17 @@ static int adv7511_probe(struct i2c_client *i2c)
if (ret && ret != -ENODEV)
return ret;
- if (adv7511->info->link_config)
+ if (adv7511->info->link_config) {
ret = adv7511_parse_dt(dev->of_node, &link_config);
- else
- ret = adv7533_parse_dt(dev->of_node, adv7511);
- if (ret)
- return ret;
+ if (ret)
+ return ret;
+ }
+
+ if (adv7511->info->has_dsi) {
+ host_node = adv7533_parse_dt(dev->of_node, adv7511);
+ if (IS_ERR(host_node))
+ return PTR_ERR(host_node);
+ }
ret = adv7511_init_regulators(adv7511);
if (ret)
@@ -1343,9 +1349,11 @@ static int adv7511_probe(struct i2c_client *i2c)
}
if (adv7511->info->has_dsi) {
- ret = adv7533_attach_dsi(adv7511);
+ ret = adv7533_attach_dsi(adv7511, host_node);
if (ret)
goto err_unregister_audio;
+
+ of_node_put(host_node);
}
return 0;
@@ -1362,6 +1370,8 @@ static int adv7511_probe(struct i2c_client *i2c)
err_i2c_unregister_edid:
i2c_unregister_device(adv7511->i2c_edid);
uninit_regulators:
+ if (host_node)
+ of_node_put(host_node);
adv7511_uninit_regulators(adv7511);
return ret;
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7533.c
b/drivers/gpu/drm/bridge/adv7511/adv7533.c
index 4481489aaf5e..5d0e55ef4028 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7533.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7533.c
@@ -131,7 +131,7 @@ int adv7533_patch_cec_registers(struct adv7511 *adv)
ARRAY_SIZE(adv7533_cec_fixed_registers));
}
-int adv7533_attach_dsi(struct adv7511 *adv)
+int adv7533_attach_dsi(struct adv7511 *adv, struct device_node *host_node)
{
struct device *dev = &adv->i2c_main->dev;
struct mipi_dsi_host *host;
@@ -142,7 +142,7 @@ int adv7533_attach_dsi(struct adv7511 *adv)
.node = NULL,
};
- host = of_find_mipi_dsi_host_by_node(adv->host_node);
+ host = of_find_mipi_dsi_host_by_node(host_node);
if (!host)
return dev_err_probe(dev, -EPROBE_DEFER,
"failed to find dsi host\n");
@@ -166,22 +166,22 @@ int adv7533_attach_dsi(struct adv7511 *adv)
return 0;
}
-int adv7533_parse_dt(struct device_node *np, struct adv7511 *adv)
+struct device_node *adv7533_parse_dt(struct device_node *np,
+ struct adv7511 *adv)
{
+ struct device_node *host_node;
u32 num_lanes;
of_property_read_u32(np, "adi,dsi-lanes", &num_lanes);
if (num_lanes < 1 || num_lanes > 4)
- return -EINVAL;
+ return ERR_PTR(-EINVAL);
adv->num_dsi_lanes = num_lanes;
- adv->host_node = of_graph_get_remote_node(np, 0, 0);
- if (!adv->host_node)
- return -ENODEV;
-
- of_node_put(adv->host_node);
+ host_node = of_graph_get_remote_node(np, 0, 0);
+ if (!host_node)
+ return ERR_PTR(-ENODEV);
adv->use_timing_gen = !of_property_read_bool(np,
"adi,disable-timing-generator");
@@ -190,5 +190,5 @@ int adv7533_parse_dt(struct device_node *np, struct adv7511
*adv)
adv->rgb = true;
adv->embedded_sync = false;
- return 0;
+ return host_node;
}
--
2.43.0
