[PATCH 5.16 102/186] auxdisplay: lcd2s: Fix memory leak in ->remove()

From: Greg Kroah-Hartman
Date: Mon Mar 07 2022 - 05:26:30 EST


From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

commit 898c0a15425a5bcaa8d44bd436eae5afd2483796 upstream.

Once allocated the struct lcd2s_data is never freed.
Fix the memory leak by switching to devm_kzalloc().

Fixes: 8c9108d014c5 ("auxdisplay: add a driver for lcd2s character display")
Cc: Lars Poeschel <poeschel@xxxxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/auxdisplay/lcd2s.c | 18 +++++++-----------
1 file changed, 7 insertions(+), 11 deletions(-)

--- a/drivers/auxdisplay/lcd2s.c
+++ b/drivers/auxdisplay/lcd2s.c
@@ -298,6 +298,10 @@ static int lcd2s_i2c_probe(struct i2c_cl
I2C_FUNC_SMBUS_WRITE_BLOCK_DATA))
return -EIO;

+ lcd2s = devm_kzalloc(&i2c->dev, sizeof(*lcd2s), GFP_KERNEL);
+ if (!lcd2s)
+ return -ENOMEM;
+
/* Test, if the display is responding */
err = lcd2s_i2c_smbus_write_byte(i2c, LCD2S_CMD_DISPLAY_OFF);
if (err < 0)
@@ -307,12 +311,6 @@ static int lcd2s_i2c_probe(struct i2c_cl
if (!lcd)
return -ENOMEM;

- lcd2s = kzalloc(sizeof(struct lcd2s_data), GFP_KERNEL);
- if (!lcd2s) {
- err = -ENOMEM;
- goto fail1;
- }
-
lcd->drvdata = lcd2s;
lcd2s->i2c = i2c;
lcd2s->charlcd = lcd;
@@ -321,24 +319,22 @@ static int lcd2s_i2c_probe(struct i2c_cl
err = device_property_read_u32(&i2c->dev, "display-height-chars",
&lcd->height);
if (err)
- goto fail2;
+ goto fail1;

err = device_property_read_u32(&i2c->dev, "display-width-chars",
&lcd->width);
if (err)
- goto fail2;
+ goto fail1;

lcd->ops = &lcd2s_ops;

err = charlcd_register(lcd2s->charlcd);
if (err)
- goto fail2;
+ goto fail1;

i2c_set_clientdata(i2c, lcd2s);
return 0;

-fail2:
- kfree(lcd2s);
fail1:
kfree(lcd);
return err;