Help - invalid count value
by Chat Overlay Streaming
Hi there,
I tried to use the TPM2 AES256 / AES256CTR to encrypt a file. When I ran
the following command, I got an error message in an infinite loop and had
to reboot my machine.
$ tpm2_encryptdecrypt -c 0x81010000 --iv=iv.input:iv.output -p ${pswd} -o
enc_test.data test.data
The error message was
tpm tpm0 invalid count value ffffffff 1000
tpm tpm0 invalid count value ffffffff 1000
...
tpm tpm0 invalid count value ffffffff 1000
Digging the location where the error message comes from, I found it was in
the tpm driver file: file tpm-interface.c
static ssize_t *tpm_try_transmit*(struct tpm_chip *chip, void *buf, size_t
bufsiz)
{
struct tpm_header *header = buf;
...
*count = be32_to_cpu(header->length); // ---> count = ffffffff *
...
*if (count > bufsiz) { // ---> bufsiz = 1000 dev_err(&chip->dev,
"invalid count value %x %zx\n", count, bufsiz); *return
-E2BIG;
* }*
....
}
My question is did someone meet the same problem? And how can I debug this
problem?
I double checked the tpm2-abrmd service. It was running okay.
The builds for my test are:
1. rpi-kernel: 5.4.y
2. tpm2-tss: 3.0.x
3. tpm2-abrmd: 2.3.2
4. tpm2-tools: 4.2.X
5. tpm2-tss-engine: v1.1.x
My test environments:
RPI 3B & 4B
AES in the TPM was enabled.
Attached is my test script.
Thanks a lot,
Ben
