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FAILED: patch "[PATCH] leds: lm3697: Fix out-of-bound access" failed to apply to 5.9-stable tree

PATCH [email protected] 3 participants 4 messages Nov 3, 2020 – Nov 25, 2020

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#0 lore raw

The patch below does not apply to the 5.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 98d278ca00bd8f62c8bc98bd9e65372d16eb6956 Mon Sep 17 00:00:00 2001
From: Gabriel David <[email protected]>
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 <[email protected]>
[removed extra rename, minor tweaks]
Signed-off-by Pavel Machek <[email protected]>
Cc [email protected]
drivers/leds/leds-lm3697.c +5 -3
index 64c0794801e6..7d216cdb91a8 100644
@@ -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);
#1 lore raw

Hi Greg,

Quoted 5 lines · On Tue, Nov 03, 2020 at 12:58:26PM +0100, [email protected] wrote:

The patch below does not apply to the 5.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

Here is the backport. Please consider for 5.9-stable.

--
Regards
Sudip

From cbaecee1e0a2aee549ecbe7f2f66a767794faef8 Mon Sep 17 00:00:00 2001
From: Gabriel David <[email protected]>
Date: Fri, 2 Oct 2020 18:27:00 -0400
Subject: [PATCH] leds: lm3697: Fix out-of-bound access

commit 98d278ca00bd8f62c8bc98bd9e65372d16eb6956 upstream

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 <[email protected]>
[removed extra rename, minor tweaks]
Signed-off-by Pavel Machek <[email protected]>
Cc [email protected]
[sudip: use client->dev]
Signed-off-by Sudip Mukherjee <[email protected]>
---
 drivers/leds/leds-lm3697.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)
drivers/leds/leds-lm3697.c +5 -3
index 024983088d59..31f5ed486839 100644
@@ -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(&priv->client->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)

@@ -307,8 +308,8 @@ static int lm3697_probe(struct i2c_client *client,
 	int ret;
 
 	count = device_get_child_node_count(&client->dev);
-	if (!count) {
-		dev_err(&client->dev, "LEDs are not defined in device tree!");
+	if (!count || count > LM3697_MAX_CONTROL_BANKS) {
+		dev_err(&client->dev, "Strange device tree!");
 		return -ENODEV;
 	}
 

@@ -322,6 +323,7 @@ static int lm3697_probe(struct i2c_client *client,
 
 	led->client = client;
 	led->dev = &client->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);
Signature · 1 line
2.11.0
author maintainer
#2 lore raw
Quoted 10 lines · Sudip Mukherjee

Hi Greg,

Quoted 5 lines · On Tue, Nov 03, 2020 at 12:58:26PM +0100, [email protected] wrote:

The patch below does not apply to the 5.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

Here is the backport. Please consider for 5.9-stable.

Now applied, thanks.

greg k-h

#3 lore raw
Quoted 5 lines · Greg KH
Quoted 4 lines · Sudip Mukherjee

Hi Greg,

Quoted 1 line · On Tue, Nov 03, 2020 at 12:58:26PM +0100, [email protected] wrote:
Quoted 8 lines
Quoted 6 lines
Quoted 4 lines

The patch below does not apply to the 5.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

Here is the backport. Please consider for 5.9-stable.

Now applied, thanks.

Note that this is theoretical problem as device trees triggering it are not circulating in the wild.

Best regards,
Pavel

Signature · 1 line
http://www.livejournal.com/~pavelmachek