diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index 324561845dc2375a4264101851ab7454cbff44e2..1dfc37e33c02de7d86b289021b10625a2c3340a9 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -198,8 +198,7 @@ static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count)
 
 	memcpy_fromio(buf, priv->rsp, 6);
 	expected = be32_to_cpup((__be32 *) &buf[2]);
-
-	if (expected > count)
+	if (expected > count || expected < 6)
 		return -EIO;
 
 	memcpy_fromio(&buf[6], &priv->rsp[6], expected - 6);