On Tue, 2014-04-15 at 14:21 -0400, Stephen Smalley wrote:
> On 04/15/2014 12:40 PM, Stephen Smalley wrote:
> > On 04/15/2014 12:27 PM, Richard Haines wrote:
> >> The current detection of duplicate rules does not cover the state->out
> >> policy and therefore will duplicate filename transition rules if already
> >> present.
> >>
> >> Signed-off-by: Richard Haines <richard_c_haines@xxxxxxxxxxxxxx>
> >> ---
> >> libsepol/src/expand.c | 14 ++++++++++++++
> >> 1 file changed, 14 insertions(+)
> >>
> >> diff --git a/libsepol/src/expand.c b/libsepol/src/expand.c
> >> index acb6906..e908fdb 100644
> >> --- a/libsepol/src/expand.c
> >> +++ b/libsepol/src/expand.c
> >> @@ -1534,6 +1534,20 @@ static int expand_filename_trans(expand_state_t *state, filename_trans_rule_t *r
> >> if (cur_trans)
> >> continue;
> >>
> >> + /* Now check if duplicate rule in state->out policy */
> >> + cur_trans = state->out->filename_trans;
> >> +
> >> + while (cur_trans) {
> >> + if (cur_trans->stype == (i + 1) &&
> >> + cur_trans->ttype == (j + 1) &&
> >> + cur_trans->tclass == cur_rule->tclass &&
> >> + !strcmp(cur_trans->name, cur_rule->name))
> >> + break;
> >> + cur_trans = cur_trans->next;
> >> + }
> >> + if (cur_trans)
> >> + continue;
> >> +
> >> new_trans = malloc(sizeof(*new_trans));
> >> if (!new_trans) {
> >> ERR(state->handle, "Out of memory!");
> >
> > Isn't this effectively a revert of:
> >
> > commit a29f6820c52b60b9028298cde9962dd140bbf9ea
> > Author: Adam Tkac <atkac@xxxxxxxxxx>
> > Date: Fri May 25 17:55:08 2012 +0200
> >
> > libsepol: filename_trans: use some better sorting to compare and merge
> >
> > The kernel switched to using a hashtab for filename_trans rules in
> > commit 2463c26d50adc282d19317013ba0ff473823ca47
> > Author: Eric Paris <eparis@xxxxxxxxxx>
> > Date: Thu Apr 28 15:11:21 2011 -0400
> >
> > SELinux: put name based create rules in a hashtable
> >
> > Is there a reason we don't do this in libsepol too?
>
> So if I am reading a29f68 correctly, it is completely wrong and should
> just be reverted. That will fix the duplicate filename transition rules
> if I am not mistaken. Then separately, we can look at bringing over the
> switch to using a hashtab that was already done in the kernel and use
> that to speed up this checking? Comments?
I think that's a good idea. The kernel hashtab and this 'fix' were done
about the same time. I intended to bring the kernel hashtab over and
got distracted and then forgot about it...
Shouldn't be a hard thing, and I believe should get us back to having
bitwise the same policy in /sys/fs/selinux/policy as we have on disk...
-Eric
