tpm: fix potential buffer overruns caused by bit glitches on the bus

[sfrench/cifs-2.6.git] / drivers / char / tpm / tpm2-cmd.c

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index c17e75348a991e355236f2040f931e940541049f..a700f8f9ead797df39de4b5ef946fb5c2c65c95b 100644 (file)
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -683,6 +683,10 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
        if (!rc) {
                data_len = be16_to_cpup(
                        (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
+               if (data_len < MIN_KEY_SIZE ||  data_len > MAX_KEY_SIZE + 1) {
+                       rc = -EFAULT;
+                       goto out;
+               }
 
                rlength = be32_to_cpu(((struct tpm2_cmd *)&buf)
                                        ->header.out.length);