Re: [PATCH 1/2] selinux: simple cleanup for cond_read_node()

[Stephen Smalley <sds@tycho.nsa.gov>]

On 06/18/2014 03:36 PM, Paul Moore wrote:
> On Sunday, June 15, 2014 01:19:01 AM Namhyung Kim wrote:
>> The node->cur_state and len can be read in a single call of next_entry().
>> And setting len before reading is a dead write so can be eliminated.
>>
>> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
>> ---
>>  security/selinux/ss/conditional.c | 9 ++-------
>>  1 file changed, 2 insertions(+), 7 deletions(-)
>>
>> diff --git a/security/selinux/ss/conditional.c
>> b/security/selinux/ss/conditional.c index 377d148e7157..4766a38fae9a 100644
>> --- a/security/selinux/ss/conditional.c
>> +++ b/security/selinux/ss/conditional.c
>> @@ -402,19 +402,14 @@ static int cond_read_node(struct policydb *p, struct
>> cond_node *node, void *fp) int rc;
>>  	struct cond_expr *expr = NULL, *last = NULL;
>>
>> -	rc = next_entry(buf, fp, sizeof(u32));
>> +	rc = next_entry(buf, fp, sizeof(buf));
> 
> This is a bit nit-picky, but how about using "sizeof(u32) * 2"?  It is more 
> consistent with the rest of the function and helps underscore that we are 

Concur - I don't want to assume that the buf size is always the same as
the next read size (e.g. we sometimes use the same buf for multiple reads).