[PATCH 5.12 001/363] KEYS: trusted: Fix memory leak on object td

From: Greg Kroah-Hartman
Date: Mon May 17 2021 - 10:08:04 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

commit 83a775d5f9bfda95b1c295f95a3a041a40c7f321 upstream.

Two error return paths are neglecting to free allocated object td,
causing a memory leak. Fix this by returning via the error return
path that securely kfree's td.

Fixes clang scan-build warning:
security/keys/trusted-keys/trusted_tpm1.c:496:10: warning: Potential
memory leak [unix.Malloc]

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 5df16caada3f ("KEYS: trusted: Fix incorrect handling of tpm_get_random()")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
Signed-off-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
security/keys/trusted-keys/trusted_tpm1.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

--- a/security/keys/trusted-keys/trusted_tpm1.c
+++ b/security/keys/trusted-keys/trusted_tpm1.c
@@ -500,10 +500,12 @@ static int tpm_seal(struct tpm_buf *tb,

ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE);
if (ret < 0)
- return ret;
+ goto out;

- if (ret != TPM_NONCE_SIZE)
- return -EIO;
+ if (ret != TPM_NONCE_SIZE) {
+ ret = -EIO;
+ goto out;
+ }

ordinal = htonl(TPM_ORD_SEAL);
datsize = htonl(datalen);