From 98d278ca00bd8f62c8bc98bd9e65372d16eb6956 Mon Sep 17 00:00:00 2001 From: Gabriel David Date: Fri, 2 Oct 2020 18:27:00 -0400 Subject: [PATCH] leds: lm3697: Fix out-of-bound access If both LED banks aren't used in device tree, an out-of-bounds condition in lm3697_init occurs because of the for loop assuming that all the banks are used. Fix it by adding a variable that contains the number of used banks. Signed-off-by: Gabriel David [removed extra rename, minor tweaks] Signed-off-by: Pavel Machek Cc: stable@kernel.org --- drivers/leds/leds-lm3697.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/leds/leds-lm3697.c b/drivers/leds/leds-lm3697.c index 64c0794801e6..7d216cdb91a8 100644 --- a/drivers/leds/leds-lm3697.c +++ b/drivers/leds/leds-lm3697.c @@ -78,6 +78,7 @@ struct lm3697 { struct mutex lock; int bank_cfg; + int num_banks; struct lm3697_led leds[]; }; @@ -180,7 +181,7 @@ static int lm3697_init(struct lm3697 *priv) if (ret) dev_err(dev, "Cannot write OUTPUT config\n"); - for (i = 0; i < LM3697_MAX_CONTROL_BANKS; i++) { + for (i = 0; i < priv->num_banks; i++) { led = &priv->leds[i]; ret = ti_lmu_common_set_ramp(&led->lmu_data); if (ret) @@ -301,8 +302,8 @@ static int lm3697_probe(struct i2c_client *client, int ret; count = device_get_child_node_count(dev); - if (!count) { - dev_err(dev, "LEDs are not defined in device tree!"); + if (!count || count > LM3697_MAX_CONTROL_BANKS) { + dev_err(dev, "Strange device tree!"); return -ENODEV; } @@ -315,6 +316,7 @@ static int lm3697_probe(struct i2c_client *client, led->client = client; led->dev = dev; + led->num_banks = count; led->regmap = devm_regmap_init_i2c(client, &lm3697_regmap_config); if (IS_ERR(led->regmap)) { ret = PTR_ERR(led->regmap);