[PATCH RFC] netlabel: remove unused param from audit_log_format()

[PATCH RFC] netlabel: remove unused param from audit_log_format()

[Alex Dewar]

Commit d3b990b7f327 ("netlabel: fix problems with mapping removal")
added a check to return an error if ret_val != 0, before ret_val is
later used in a log message. Now it will unconditionally print "...
res=0". So don't print res anymore.

Addresses-Coverity: ("Dead code")
Fixes: d3b990b7f327 ("netlabel: fix problems with mapping removal")
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
---

I wasn't sure whether it was intended that something other than ret_val
be printed in the log, so that's why I'm sending this as an RFC.


 net/netlabel/netlabel_domainhash.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
index f73a8382c275..526762b2f3a9 100644
--- a/net/netlabel/netlabel_domainhash.c
+++ b/net/netlabel/netlabel_domainhash.c
@@ -612,9 +612,8 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
 	audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
 	if (audit_buf != NULL) {
 		audit_log_format(audit_buf,
-				 " nlbl_domain=%s res=%u",
-				 entry->domain ? entry->domain : "(default)",
-				 ret_val == 0 ? 1 : 0);
+				 " nlbl_domain=%s",
+				 entry->domain ? entry->domain : "(default)");
 		audit_log_end(audit_buf);
 	}
 
-- 
2.28.0

Re: [PATCH RFC] netlabel: remove unused param from audit_log_format()

[Paul Moore]

On Thu, Aug 27, 2020 at 12:39 PM Alex Dewar <alex.dewar90@gmail.com> wrote:
>
> Commit d3b990b7f327 ("netlabel: fix problems with mapping removal")
> added a check to return an error if ret_val != 0, before ret_val is
> later used in a log message. Now it will unconditionally print "...
> res=0". So don't print res anymore.
>
> Addresses-Coverity: ("Dead code")
> Fixes: d3b990b7f327 ("netlabel: fix problems with mapping removal")
> Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
> ---
>
> I wasn't sure whether it was intended that something other than ret_val
> be printed in the log, so that's why I'm sending this as an RFC.

It's intentional for a couple of reasons:

* The people who care about audit logs like to see success/fail (e.g.
"res=X") for audit events/records, so printing this out gives them the
warm fuzzies.

* For a lot of awful reasons that I won't bore you with, we really
don't want to add/remove fields in the middle of an audit record so we
pretty much need to keep the "res=0" there even if it seems a bit
redundant.

So NACK from me, but thanks for paying attention just the same :)

>  net/netlabel/netlabel_domainhash.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
> index f73a8382c275..526762b2f3a9 100644
> --- a/net/netlabel/netlabel_domainhash.c
> +++ b/net/netlabel/netlabel_domainhash.c
> @@ -612,9 +612,8 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
>         audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
>         if (audit_buf != NULL) {
>                 audit_log_format(audit_buf,
> -                                " nlbl_domain=%s res=%u",
> -                                entry->domain ? entry->domain : "(default)",
> -                                ret_val == 0 ? 1 : 0);
> +                                " nlbl_domain=%s",
> +                                entry->domain ? entry->domain : "(default)");
>                 audit_log_end(audit_buf);
>         }
>

-- 
paul moore
www.paul-moore.com

Re: [PATCH RFC] netlabel: remove unused param from audit_log_format()

[Alex Dewar]

On Thu, Aug 27, 2020 at 01:00:58PM -0400, Paul Moore wrote:
> On Thu, Aug 27, 2020 at 12:39 PM Alex Dewar <alex.dewar90@gmail.com> wrote:
> >
> > Commit d3b990b7f327 ("netlabel: fix problems with mapping removal")
> > added a check to return an error if ret_val != 0, before ret_val is
> > later used in a log message. Now it will unconditionally print "...
> > res=0". So don't print res anymore.
> >
> > Addresses-Coverity: ("Dead code")
> > Fixes: d3b990b7f327 ("netlabel: fix problems with mapping removal")
> > Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
> > ---
> >
> > I wasn't sure whether it was intended that something other than ret_val
> > be printed in the log, so that's why I'm sending this as an RFC.
> 
> It's intentional for a couple of reasons:
> 
> * The people who care about audit logs like to see success/fail (e.g.
> "res=X") for audit events/records, so printing this out gives them the
> warm fuzzies.
> 
> * For a lot of awful reasons that I won't bore you with, we really
> don't want to add/remove fields in the middle of an audit record so we
> pretty much need to keep the "res=0" there even if it seems a bit
> redundant.
> 
> So NACK from me, but thanks for paying attention just the same :)

Would you rather just have an explicit "res=0" in there, without looking
at ret_val? The thing is that ret_val will *always* be zero at this point in
the code, because, if not, the function will already have returned.
That's why Coverity flagged it up as a redundant check.

> 
> >  net/netlabel/netlabel_domainhash.c | 5 ++---
> >  1 file changed, 2 insertions(+), 3 deletions(-)
> >
> > diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
> > index f73a8382c275..526762b2f3a9 100644
> > --- a/net/netlabel/netlabel_domainhash.c
> > +++ b/net/netlabel/netlabel_domainhash.c
> > @@ -612,9 +612,8 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
> >         audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
> >         if (audit_buf != NULL) {
> >                 audit_log_format(audit_buf,
> > -                                " nlbl_domain=%s res=%u",
> > -                                entry->domain ? entry->domain : "(default)",
> > -                                ret_val == 0 ? 1 : 0);
> > +                                " nlbl_domain=%s",
> > +                                entry->domain ? entry->domain : "(default)");
> >                 audit_log_end(audit_buf);
> >         }
> >
> 
> -- 
> paul moore
> www.paul-moore.com

Re: [PATCH RFC] netlabel: remove unused param from audit_log_format()

[Alex Dewar]

On Thu, Aug 27, 2020 at 06:06:34PM +0100, Alex Dewar wrote:
> On Thu, Aug 27, 2020 at 01:00:58PM -0400, Paul Moore wrote:
> > On Thu, Aug 27, 2020 at 12:39 PM Alex Dewar <alex.dewar90@gmail.com> wrote:
> > >
> > > Commit d3b990b7f327 ("netlabel: fix problems with mapping removal")
> > > added a check to return an error if ret_val != 0, before ret_val is
> > > later used in a log message. Now it will unconditionally print "...
> > > res=0". So don't print res anymore.
> > >
> > > Addresses-Coverity: ("Dead code")
> > > Fixes: d3b990b7f327 ("netlabel: fix problems with mapping removal")
> > > Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
> > > ---
> > >
> > > I wasn't sure whether it was intended that something other than ret_val
> > > be printed in the log, so that's why I'm sending this as an RFC.
> > 
> > It's intentional for a couple of reasons:
> > 
> > * The people who care about audit logs like to see success/fail (e.g.
> > "res=X") for audit events/records, so printing this out gives them the
> > warm fuzzies.
> > 
> > * For a lot of awful reasons that I won't bore you with, we really
> > don't want to add/remove fields in the middle of an audit record so we
> > pretty much need to keep the "res=0" there even if it seems a bit
> > redundant.
> > 
> > So NACK from me, but thanks for paying attention just the same :)
> 
> Would you rather just have an explicit "res=0" in there, without looking
> at ret_val? The thing is that ret_val will *always* be zero at this point in
> the code, because, if not, the function will already have returned.
> That's why Coverity flagged it up as a redundant check.

Sorry, I meant "res=1". The code will always print res=1, because
ret_val is always 0.
> 
> > 
> > >  net/netlabel/netlabel_domainhash.c | 5 ++---
> > >  1 file changed, 2 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
> > > index f73a8382c275..526762b2f3a9 100644
> > > --- a/net/netlabel/netlabel_domainhash.c
> > > +++ b/net/netlabel/netlabel_domainhash.c
> > > @@ -612,9 +612,8 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
> > >         audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
> > >         if (audit_buf != NULL) {
> > >                 audit_log_format(audit_buf,
> > > -                                " nlbl_domain=%s res=%u",
> > > -                                entry->domain ? entry->domain : "(default)",
> > > -                                ret_val == 0 ? 1 : 0);
> > > +                                " nlbl_domain=%s",
> > > +                                entry->domain ? entry->domain : "(default)");
> > >                 audit_log_end(audit_buf);
> > >         }
> > >
> > 
> > -- 
> > paul moore
> > www.paul-moore.com

Re: [PATCH RFC] netlabel: remove unused param from audit_log_format()

[Paul Moore]

On Thu, Aug 27, 2020 at 1:20 PM Alex Dewar <alex.dewar90@gmail.com> wrote:
> On Thu, Aug 27, 2020 at 06:06:34PM +0100, Alex Dewar wrote:
> > On Thu, Aug 27, 2020 at 01:00:58PM -0400, Paul Moore wrote:
> > > On Thu, Aug 27, 2020 at 12:39 PM Alex Dewar <alex.dewar90@gmail.com> wrote:
> > > >
> > > > Commit d3b990b7f327 ("netlabel: fix problems with mapping removal")
> > > > added a check to return an error if ret_val != 0, before ret_val is
> > > > later used in a log message. Now it will unconditionally print "...
> > > > res=0". So don't print res anymore.
> > > >
> > > > Addresses-Coverity: ("Dead code")
> > > > Fixes: d3b990b7f327 ("netlabel: fix problems with mapping removal")
> > > > Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
> > > > ---
> > > >
> > > > I wasn't sure whether it was intended that something other than ret_val
> > > > be printed in the log, so that's why I'm sending this as an RFC.
> > >
> > > It's intentional for a couple of reasons:
> > >
> > > * The people who care about audit logs like to see success/fail (e.g.
> > > "res=X") for audit events/records, so printing this out gives them the
> > > warm fuzzies.
> > >
> > > * For a lot of awful reasons that I won't bore you with, we really
> > > don't want to add/remove fields in the middle of an audit record so we
> > > pretty much need to keep the "res=0" there even if it seems a bit
> > > redundant.
> > >
> > > So NACK from me, but thanks for paying attention just the same :)
> >
> > Would you rather just have an explicit "res=0" in there, without looking
> > at ret_val? The thing is that ret_val will *always* be zero at this point in
> > the code, because, if not, the function will already have returned.
> > That's why Coverity flagged it up as a redundant check.
>
> Sorry, I meant "res=1". The code will always print res=1, because
> ret_val is always 0.

That's okay, I can't tell you how many times I've made that mistake
with "res=" :)

Anyway, yes at that point ret_val should always be 0, and "res=X"
should always be "res=1", so if you wanted to change it to a fixed
value so you could get rid of the ternary statement that would be
okay.

> > > >  net/netlabel/netlabel_domainhash.c | 5 ++---
> > > >  1 file changed, 2 insertions(+), 3 deletions(-)
> > > >
> > > > diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
> > > > index f73a8382c275..526762b2f3a9 100644
> > > > --- a/net/netlabel/netlabel_domainhash.c
> > > > +++ b/net/netlabel/netlabel_domainhash.c
> > > > @@ -612,9 +612,8 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
> > > >         audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
> > > >         if (audit_buf != NULL) {
> > > >                 audit_log_format(audit_buf,
> > > > -                                " nlbl_domain=%s res=%u",
> > > > -                                entry->domain ? entry->domain : "(default)",
> > > > -                                ret_val == 0 ? 1 : 0);
> > > > +                                " nlbl_domain=%s",
> > > > +                                entry->domain ? entry->domain : "(default)");
> > > >                 audit_log_end(audit_buf);
> > > >         }
> > > >

-- 
paul moore
www.paul-moore.com

[PATCH v2] netlabel: remove unused param from audit_log_format()

[Alex Dewar]

Commit d3b990b7f327 ("netlabel: fix problems with mapping removal")
added a check to return an error if ret_val != 0, before ret_val is
later used in a log message. Now it will unconditionally print "...
res=1". So just drop the check.

Addresses-Coverity: ("Dead code")
Fixes: d3b990b7f327 ("netlabel: fix problems with mapping removal")
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
---
v2: Still print the res field, because it's useful (Paul)

 net/netlabel/netlabel_domainhash.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
index f73a8382c275e..dc8c39f51f7d3 100644
--- a/net/netlabel/netlabel_domainhash.c
+++ b/net/netlabel/netlabel_domainhash.c
@@ -612,9 +612,8 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
 	audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
 	if (audit_buf != NULL) {
 		audit_log_format(audit_buf,
-				 " nlbl_domain=%s res=%u",
-				 entry->domain ? entry->domain : "(default)",
-				 ret_val == 0 ? 1 : 0);
+				 " nlbl_domain=%s res=1",
+				 entry->domain ? entry->domain : "(default)");
 		audit_log_end(audit_buf);
 	}
 
-- 
2.28.0

Re: [PATCH v2] netlabel: remove unused param from audit_log_format()

[Paul Moore]

On Fri, Aug 28, 2020 at 9:56 AM Alex Dewar <alex.dewar90@gmail.com> wrote:
>
> Commit d3b990b7f327 ("netlabel: fix problems with mapping removal")
> added a check to return an error if ret_val != 0, before ret_val is
> later used in a log message. Now it will unconditionally print "...
> res=1". So just drop the check.
>
> Addresses-Coverity: ("Dead code")
> Fixes: d3b990b7f327 ("netlabel: fix problems with mapping removal")
> Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
> ---
> v2: Still print the res field, because it's useful (Paul)
>
>  net/netlabel/netlabel_domainhash.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)

Thanks Alex.

Acked-by: Paul Moore <paul@paul-moore.com>

> diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
> index f73a8382c275e..dc8c39f51f7d3 100644
> --- a/net/netlabel/netlabel_domainhash.c
> +++ b/net/netlabel/netlabel_domainhash.c
> @@ -612,9 +612,8 @@ int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
>         audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
>         if (audit_buf != NULL) {
>                 audit_log_format(audit_buf,
> -                                " nlbl_domain=%s res=%u",
> -                                entry->domain ? entry->domain : "(default)",
> -                                ret_val == 0 ? 1 : 0);
> +                                " nlbl_domain=%s res=1",
> +                                entry->domain ? entry->domain : "(default)");
>                 audit_log_end(audit_buf);
>         }
>
> --
> 2.28.0
>


-- 
paul moore
www.paul-moore.com

Re: [PATCH v2] netlabel: remove unused param from audit_log_format()

[David Miller]

From: Alex Dewar <alex.dewar90@gmail.com>
Date: Fri, 28 Aug 2020 14:55:23 +0100

> Commit d3b990b7f327 ("netlabel: fix problems with mapping removal")
> added a check to return an error if ret_val != 0, before ret_val is
> later used in a log message. Now it will unconditionally print "...
> res=1". So just drop the check.
> 
> Addresses-Coverity: ("Dead code")
> Fixes: d3b990b7f327 ("netlabel: fix problems with mapping removal")
> Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
> ---
> v2: Still print the res field, because it's useful (Paul)

Applied to net-next, thank you.