Re: [PATCH ima-evm-utils] Add sanity check for file parameter of ima_boot_aggregate

[Mimi Zohar <zohar@linux.ibm.com>]

On Fri, 2020-07-17 at 14:04 +0200, Petr Vorel wrote:
> Parameter expects to be a copy of
> /sys/kernel/security/tpm0/binary_bios_measurements (i.e. regular file,
> not a directory, block or character device, socket, ...)
> 
> Fixes: f49e982 ("ima-evm-utils: read the TPM 1.2 binary_bios_measurements")
> 
> Signed-off-by: Petr Vorel <pvorel@suse.cz>
> ---
> Hi Mimi,
> 
> feel free to modify this patchset to fits your needs (unless I'm wrong
> and this should not be applied at all).
> 

Thanks!  I made minor changes as noted below.  A subsequent patch
makes a similar change for the new TPM 1.2 PCRs.

> 
>  src/evmctl.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/src/evmctl.c b/src/evmctl.c
> index 04dc2ad..3ad5039 100644
> --- a/src/evmctl.c
> +++ b/src/evmctl.c
> @@ -2082,6 +2082,13 @@ static int read_binary_bios_measurements(char *file, struct tpm_bank_info *bank)
>  	int len;
>  	int i;
> 
> +	struct stat s;
> +	stat(file, &s);

Checked stat return code.


> +	if (!S_ISREG(s.st_mode)) {
> +		log_errno("Not a regular file or link to regular file.\n");

Prefixed message with "Bios event log: not ..."

> +		return 1;
> +	}
> +
>  	fp = fopen(file, "r");
>  	if (!fp) {
>  		log_errno("Failed to open TPM 1.2 event log.\n");