[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Date: Sun, 11 Mar 2018 18:01:05 -0400
From: Mimi Zohar <zohar@...ux.vnet.ibm.com>
To: Tycho Andersen <tycho@...ho.ws>,
Dmitry Kasatkin
<dmitry.kasatkin@...il.com>
Cc: linux-integrity@...r.kernel.org, linux-kernel@...r.kernel.org,
kernel-hardening@...ts.openwall.com
Subject: Re: [PATCH v3] ima: drop vla in ima_audit_measurement()
On Thu, 2018-03-08 at 16:08 -0700, Tycho Andersen wrote:
> In keeping with the directive to get rid of VLAs [1], let's drop the VLA
> from ima_audit_measurement(). We need to adjust the return type of
> ima_audit_measurement, because now this function can fail if an allocation
> fails.
>
> [1]: https://lkml.org/lkml/2018/3/7/621
>
> v2: just use audit_log_format instead of doing a second allocation
> v3: ignore failures in ima_audit_measurement()
>
> Signed-off-by: Tycho Andersen <tycho@...ho.ws>
Thanks, this patch has been applied.
Mimi
> ---
> security/integrity/ima/ima_api.c | 16 ++++++++++------
> 1 file changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
> index 08fe405338e1..2aab9170ef68 100644
> --- a/security/integrity/ima/ima_api.c
> +++ b/security/integrity/ima/ima_api.c
> @@ -308,14 +308,17 @@ void ima_audit_measurement(struct integrity_iint_cache *iint,
> const unsigned char *filename)
> {
> struct audit_buffer *ab;
> - char hash[(iint->ima_hash->length * 2) + 1];
> + char *hash;
> const char *algo_name = hash_algo_name[iint->ima_hash->algo];
> - char algo_hash[sizeof(hash) + strlen(algo_name) + 2];
> int i;
>
> if (iint->flags & IMA_AUDITED)
> return;
>
> + hash = kzalloc((iint->ima_hash->length * 2) + 1, GFP_KERNEL);
> + if (!hash)
> + return;
> +
> for (i = 0; i < iint->ima_hash->length; i++)
> hex_byte_pack(hash + (i * 2), iint->ima_hash->digest[i]);
> hash[i * 2] = '\0';
> @@ -323,18 +326,19 @@ void ima_audit_measurement(struct integrity_iint_cache *iint,
> ab = audit_log_start(current->audit_context, GFP_KERNEL,
> AUDIT_INTEGRITY_RULE);
> if (!ab)
> - return;
> + goto out;
>
> audit_log_format(ab, "file=");
> audit_log_untrustedstring(ab, filename);
> - audit_log_format(ab, " hash=");
> - snprintf(algo_hash, sizeof(algo_hash), "%s:%s", algo_name, hash);
> - audit_log_untrustedstring(ab, algo_hash);
> + audit_log_format(ab, " hash=\"%s:%s\"", algo_name, hash);
>
> audit_log_task_info(ab, current);
> audit_log_end(ab);
>
> iint->flags |= IMA_AUDITED;
> +out:
> + kfree(hash);
> + return;
> }
>
> /*
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
