[PATCH] tpm: Fix memory leak in tpmm_chip_alloc

From: GUO Zihua
Date: Mon Mar 07 2022 - 06:22:29 EST


Fix a memory leak in tpmm_chip_alloc. devm_add_action_or_reset would
call put_device on error, while tpm->devs is left untouched. Call
put_device on tpm->devs as well if devm_add_action_or_reset returns an
error.

Fixes: fdc915f7f719 ("tpm: expose spaces via a device link /dev/tpmrm")
Signed-off-by: GUO Zihua <guozihua@xxxxxxxxxx>
---
drivers/char/tpm/tpm-chip.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index b009e7479b70..0a92334e8c40 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -308,6 +308,12 @@ static int tpm_class_shutdown(struct device *dev)
return 0;
}

+static void tpm_chip_free(struct tpm_chip *chip)
+{
+ put_device(&chip->devs);
+ put_device(&chip->dev);
+}
+
/**
* tpm_chip_alloc() - allocate a new struct tpm_chip instance
* @pdev: device to which the chip is associated
@@ -396,8 +402,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
return chip;

out:
- put_device(&chip->devs);
- put_device(&chip->dev);
+ tpm_chip_free(chip);
return ERR_PTR(rc);
}
EXPORT_SYMBOL_GPL(tpm_chip_alloc);
@@ -420,8 +425,8 @@ struct tpm_chip *tpmm_chip_alloc(struct device *pdev,
return chip;

rc = devm_add_action_or_reset(pdev,
- (void (*)(void *)) put_device,
- &chip->dev);
+ (void (*)(void *)) tpm_chip_free,
+ chip);
if (rc)
return ERR_PTR(rc);

--
2.17.1