[PATCH 1/1] Solves Bug 1462 - `nft -j list set` does not show counters

[PATCH 1/1] Solves Bug 1462 - `nft -j list set` does not show counters

[Gopal Yadav]

Solves Bug 1462 - `nft -j list set` does not show counters

Signed-off-by: Gopal Yadav <gopunop@gmail.com>
---
 src/json.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/json.c b/src/json.c
index 5856f9fc..6ad48fdd 100644
--- a/src/json.c
+++ b/src/json.c
@@ -589,7 +589,7 @@ json_t *set_elem_expr_json(const struct expr *expr, struct output_ctx *octx)
 		return NULL;
 
 	/* these element attributes require formal set elem syntax */
-	if (expr->timeout || expr->expiration || expr->comment) {
+	if (expr->timeout || expr->expiration || expr->comment || expr->stmt) {
 		root = json_pack("{s:o}", "val", root);
 
 		if (expr->timeout) {
@@ -604,6 +604,10 @@ json_t *set_elem_expr_json(const struct expr *expr, struct output_ctx *octx)
 			tmp = json_string(expr->comment);
 			json_object_set_new(root, "comment", tmp);
 		}
+		if(expr->stmt) {
+			tmp = expr->stmt->ops->json(expr->stmt, octx);
+			json_object_update(root, tmp);
+		}
 		return json_pack("{s:o}", "elem", root);
 	}
 
-- 
2.17.1

Re: [PATCH 1/1] Solves Bug 1462 - `nft -j list set` does not show counters

[Jose M. Guisado]

Hi Gopal,

On 3/10/20 14:58, Gopal Yadav wrote:
> Solves Bug 1462 - `nft -j list set` does not show counters
> 
> Signed-off-by: Gopal Yadav <gopunop@gmail.com>
> ---
>   src/json.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/src/json.c b/src/json.c
> index 5856f9fc..6ad48fdd 100644
> --- a/src/json.c
> +++ b/src/json.c
> @@ -589,7 +589,7 @@ json_t *set_elem_expr_json(const struct expr *expr, struct output_ctx *octx)
>   		return NULL;
>   
>   	/* these element attributes require formal set elem syntax */
> -	if (expr->timeout || expr->expiration || expr->comment) {
> +	if (expr->timeout || expr->expiration || expr->comment || expr->stmt) {
>   		root = json_pack("{s:o}", "val", root);
>   
>   		if (expr->timeout) {
> @@ -604,6 +604,10 @@ json_t *set_elem_expr_json(const struct expr *expr, struct output_ctx *octx)
>   			tmp = json_string(expr->comment);
>   			json_object_set_new(root, "comment", tmp);
>   		}
> +		if(expr->stmt) {
> +			tmp = expr->stmt->ops->json(expr->stmt, octx);

You can compact this using stmt_print_json

> +			json_object_update(root, tmp);

ASAN reports memleaks when using json_object_update. You should use 
json_object_update_new, or maybe json_object_update_missing_new to 
ensure only new keys are created.

> +		}
>   		return json_pack("{s:o}", "elem", root);
>   	}
>   
> 

Re: [PATCH 1/1] Solves Bug 1462 - `nft -j list set` does not show counters

[Gopal Yadav]

On Tue, Oct 6, 2020 at 4:03 PM Jose M. Guisado <guigom@riseup.net> wrote:
>
> Hi Gopal,
>
> On 3/10/20 14:58, Gopal Yadav wrote:
> > +                     tmp = expr->stmt->ops->json(expr->stmt, octx);
>
> You can compact this using stmt_print_json
>
> > +                     json_object_update(root, tmp);
>
> ASAN reports memleaks when using json_object_update. You should use
> json_object_update_new, or maybe json_object_update_missing_new to
> ensure only new keys are created.

Should I always run ASAN before submitting patches as a regular practice?
json_object_update_missing_new() was raising a warning so I have used
json_object_update_missing() in the updated patch.

Re: [PATCH 1/1] Solves Bug 1462 - `nft -j list set` does not show counters

[Jose M. Guisado]

On 6/10/20 14:42, Gopal Yadav wrote:
> Should I always run ASAN before submitting patches as a regular practice?

I usually check for leaks when submitting patches, using either ASAN or 
Valgrind.

> json_object_update_missing_new() was raising a warning so I have used
> json_object_update_missing() in the updated patch.

I've been unable to reproduce said warning when using 
json_object_update_missing_new.

You need to use the *_new function, because it will call json_decref on 
tmp for you. If not the reference to tmp is leaked.

You should version your patches, have a look at the patch submission 
guidelines in the nftables wiki [1]

[1] 
https://wiki.nftables.org/wiki-nftables/index.php/Portal:DeveloperDocs/Patch_submission_guidelines

Re: [PATCH 1/1] Solves Bug 1462 - `nft -j list set` does not show counters

[Gopal Yadav]

On Tue, Oct 6, 2020 at 7:15 PM Jose M. Guisado <guigom@riseup.net> wrote:
>
> On 6/10/20 14:42, Gopal Yadav wrote:
> > Should I always run ASAN before submitting patches as a regular practice?
>
> I usually check for leaks when submitting patches, using either ASAN or
> Valgrind.
>
> > json_object_update_missing_new() was raising a warning so I have used
> > json_object_update_missing() in the updated patch.
>
> I've been unable to reproduce said warning when using
> json_object_update_missing_new.
>
> You need to use the *_new function, because it will call json_decref on
> tmp for you. If not the reference to tmp is leaked.

Since on using *_new() build fails, should I call json_decref(tmp)
explicitly after json_object_update_missing()?

I couldn't get ASAN to run, but I ran valgrind by doing `valgrind nft
list ruleset` on both versions, with & without json_decref(tmp). Both
of them produce the same output which says no leaks:

==5967== Memcheck, a memory error detector
==5967== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==5967== Using Valgrind-3.13.0 and LibVEX; rerun with -h for copyright info
==5967== Command: nft list ruleset
==5967==
table inet dev {
    set ports_udp {
        type inet_service
        size 65536
        flags dynamic,timeout
        timeout 30d
        elements = { 53 expires 29d6h14m26s268ms counter packets 0 bytes 0 }
    }
}
==5967==
==5967== HEAP SUMMARY:
==5967==     in use at exit: 0 bytes in 0 blocks
==5967==   total heap usage: 78 allocs, 78 frees, 390,728 bytes allocated
==5967==
==5967== All heap blocks were freed -- no leaks are possible
==5967==
==5967== For counts of detected and suppressed errors, rerun with: -v
==5967== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)