Re: [PATCH v5 2/2] KEYS: Avoid false positive ENOMEM error on key read
From: Waiman Long <longman@redhat.com>
Date: 2020-03-20 00:08:08
Also in:
keyrings, linux-integrity, linux-security-module, lkml
On 3/19/20 3:46 PM, Jarkko Sakkinen wrote:
On Wed, Mar 18, 2020 at 06:14:57PM -0400, Waiman Long wrote:quoted
+ * It is possible, though unlikely, that the key + * changes in between the up_read->down_read period. + * If the key becomes longer, we will have to + * allocate a larger buffer and redo the key read + * again. + */ + if (!tmpbuf || unlikely(ret > tmpbuflen)) {Shouldn't you check that tmpbuflen stays below buflen (why else you had made copy of buflen otherwise)?
The check above this thunk:
if ((ret > 0) && (ret <= buflen)) {
will make sure that ret will not be larger than buflen. So tmpbuflen
will never be bigger than buflen.
Cheers,
Longman