Commit a0bcce2b authored by Dan Carpenter's avatar Dan Carpenter Committed by Jarkko Sakkinen
Browse files

tpm: Check for integer overflow in tpm2_map_response_body() 



The "4 * be32_to_cpu(data->count)" multiplication can potentially
overflow which would lead to memory corruption.  Add a check for that.

Cc: stable@vger.kernel.org
Fixes: 745b361e ("tpm: infrastructure for TPM spaces")
Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
parent 4091c004

drivers/char/tpm/tpm2-space.c

+3 −0
Original line number Diff line number Diff line
@@ -455,6 +455,9 @@ static int tpm2_map_response_body(struct tpm_chip *chip, u32 cc, u8 *rsp, 
	if (be32_to_cpu(data->capability) != TPM2_CAP_HANDLES)

		return 0;



	if (be32_to_cpu(data->count) > (UINT_MAX - TPM_HEADER_SIZE - 9) / 4)

		return -EFAULT;



	if (len != TPM_HEADER_SIZE + 9 + 4 * be32_to_cpu(data->count))

		return -EFAULT;