Re: [PATCH v3] tpm: Repeal and replace tpm_buf_init*() and tpm_buf_destroy()

[Jarkko Sakkinen <jarkko@kernel.org>]

On Tue, Jul 01, 2025 at 03:11:51AM +0300, Jarkko Sakkinen wrote:
> From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
> 
> Repeal and replace tpm_buf_init() and tpm_buf_init_sized() with
> tpm_buf_alloc(), which returns PAGE_SIZE of memory with the struct tpm_buf
> header in the beginning of the returned buffer. This leaves 4088 bytes of
> free space for data.

A minor error: it is now 4090 bytes:

struct tpm_buf {
	u16 flags;
	u16 length;
	u16 handles;
	u8 data[];
};

I guess this should be changed into:

struct tpm_buf {
	u8 flags;
	u8 handles;
	u16 length;
	u8 data[];
}

It's not strictly necessary given that we are already "above the
hardware spec" but it neither makes much sense to keep `handles`
or `flags` 16-bit words with MSB always empty in both of the
words.

BR, Jarkko