'tpm2_load_cmd' allocates a tempoary blob indirectly via 'tpm2_key_decode' but it is not freed in the failure paths. Address this by wrapping the blob into with a cleanup helper.

Cc: stable@vger.kernel.org # v5.13+ Fixes: f2219745250f ("security: keys: trusted: use ASN.1 TPM2 key format for the blobs") Signed-off-by: Jarkko Sakkinen jarkko@kernel.org --- v9: - Fixed up the commit message. It was not up to date and referred to wrong function. - Simplified the patch considereably. It was not optimally small. v8: - No changes. v7: - Fix compiler warning. v6: - A new patch in this version. --- security/keys/trusted-keys/trusted_tpm2.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c index 4467e880ebd5..225b8c9932bf 100644 --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -366,6 +366,7 @@ static int tpm2_load_cmd(struct tpm_chip *chip, struct trusted_key_options *options, u32 *blob_handle) { + u8 *blob_ref __free(kfree) = NULL; struct tpm_buf buf; unsigned int private_len; unsigned int public_len; @@ -379,6 +380,9 @@ static int tpm2_load_cmd(struct tpm_chip *chip, /* old form */ blob = payload->blob; payload->old_format = 1; + } else { + /* Bind for cleanup: */ + blob_ref = blob; }

/* new format carries keyhandle but old format doesn't */ @@ -443,8 +447,6 @@ static int tpm2_load_cmd(struct tpm_chip *chip, (__be32 *) &buf.data[TPM_HEADER_SIZE]);

out: - if (blob != payload->blob) - kfree(blob); tpm_buf_destroy(&buf);

return tpm_ret_to_err(rc);