tpm: check the chip reference before using it

If a driver calls tpm_dev_vendor_release for a device already released then the driver will oops. Signed-off-by: Andi Shyti <andi.shyti@gmail.com> Signed-off-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>

tpm: check the chip reference before using it
If a driver calls tpm_dev_vendor_release for a device already released then the driver will oops. Signed-off-by: Andi Shyti <andi.shyti@gmail.com> Signed-off-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Andi Shyti · Rajiv Andrade
1 parent dad79cb892
Showing 1 changed file with 6 additions and 0 deletions Side-by-side Diff
drivers/char/tpm/tpm.c
@@ -1330,6 +1330,9 @@
  
 void tpm_dev_vendor_release(struct tpm_chip *chip)
 {
+	if (!chip)
+		return;
+
 	if (chip->vendor.release)
 		chip->vendor.release(chip->dev);
  
@@ -1346,6 +1349,9 @@
 void tpm_dev_release(struct device *dev)
 {
 	struct tpm_chip *chip = dev_get_drvdata(dev);
+
+	if (!chip)
+		return;
  
 	tpm_dev_vendor_release(chip);
...	...	@@ -1330,6 +1330,9 @@
1330	1330
1331	1331	void tpm_dev_vendor_release(struct tpm_chip *chip)
1332	1332	{
	1333	+ if (!chip)
	1334	+ return;
	1335	+
1333	1336	if (chip->vendor.release)
1334	1337	chip->vendor.release(chip->dev);
1335	1338
...	...	@@ -1346,6 +1349,9 @@
1346	1349	void tpm_dev_release(struct device *dev)
1347	1350	{
1348	1351	struct tpm_chip *chip = dev_get_drvdata(dev);
	1352	+
	1353	+ if (!chip)
	1354	+ return;
1349	1355
1350	1356	tpm_dev_vendor_release(chip);
1351	1357