Commit 18f0fb57 authored Sep 08, 2021 by Dan Carpenter Committed by Greg Kroah-Hartman Nov 17, 2021

tpm: Check for integer overflow in tpm2_map_response_body()



commit a0bcce2b2a169e10eb265c8f0ebdd5ae4c875670 upstream.

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: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent f38f3da3

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;