[PATCH iproute2] tc_util: Fix parsing action control with space and slash

[PATCH iproute2] tc_util: Fix parsing action control with space and slash

[Roi Dayan]

For action police there is an conform-exceed action control
which can be for example "jump 2 / pipe".
The current parsing loop is doing one more iteration than necessary
and results in ok var being 3.

Example filter:

tc filter add dev enp8s0f0_0 ingress protocol ip prio 2 flower \
    verbose action police rate 100mbit burst 12m \
    conform-exceed jump 1 / pipe mirred egress redirect dev enp8s0f0_1 action drop

Before this change the command will fail.
Trying to add another "pipe" before mirred as a workaround for the stopping the loop
in ok var 3 resulting in result2 not being saved and wrong filter.

... conform-exceed jump 1 / pipe pipe mirred ...

Example dump of the action part:
... action order 1:  police 0x1 rate 100Mbit burst 12Mb mtu 2Kb action jump 1 overhead 0b  ...

Fix the behavior by removing redundant case 2 handling, either argc is over or breaking.

Example dump of the action part with the fix:
... action order 1:  police 0x1 rate 100Mbit burst 12Mb mtu 2Kb action jump 1/pipe overhead 0b ...

Signed-off-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Maor Dickman <maord@nvidia.com>
---
 tc/tc_util.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tc/tc_util.c b/tc/tc_util.c
index 48065897cee7..b82dbd5dc75d 100644
--- a/tc/tc_util.c
+++ b/tc/tc_util.c
@@ -476,7 +476,6 @@ static int parse_action_control_slash_spaces(int *argc_p, char ***argv_p,
 			NEXT_ARG();
 			/* fall-through */
 		case 0: /* fall-through */
-		case 2:
 			ret = parse_action_control(&argc, &argv,
 						   result_p, allow_num);
 			if (ret)
-- 
2.8.0

Re: [PATCH iproute2] tc_util: Fix parsing action control with space and slash

[Stephen Hemminger]

On Thu, 3 Feb 2022 14:20:46 +0200
Roi Dayan <roid@nvidia.com> wrote:

> For action police there is an conform-exceed action control
> which can be for example "jump 2 / pipe".
> The current parsing loop is doing one more iteration than necessary
> and results in ok var being 3.
> 
> Example filter:
> 
> tc filter add dev enp8s0f0_0 ingress protocol ip prio 2 flower \
>     verbose action police rate 100mbit burst 12m \
>     conform-exceed jump 1 / pipe mirred egress redirect dev enp8s0f0_1 action drop
> 
> Before this change the command will fail.
> Trying to add another "pipe" before mirred as a workaround for the stopping the loop
> in ok var 3 resulting in result2 not being saved and wrong filter.
> 
> ... conform-exceed jump 1 / pipe pipe mirred ...
> 
> Example dump of the action part:
> ... action order 1:  police 0x1 rate 100Mbit burst 12Mb mtu 2Kb action jump 1 overhead 0b  ...
> 
> Fix the behavior by removing redundant case 2 handling, either argc is over or breaking.
> 
> Example dump of the action part with the fix:
> ... action order 1:  police 0x1 rate 100Mbit burst 12Mb mtu 2Kb action jump 1/pipe overhead 0b ...
> 
> Signed-off-by: Roi Dayan <roid@nvidia.com>
> Reviewed-by: Maor Dickman <maord@nvidia.com>
> ---
>  tc/tc_util.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/tc/tc_util.c b/tc/tc_util.c
> index 48065897cee7..b82dbd5dc75d 100644
> --- a/tc/tc_util.c
> +++ b/tc/tc_util.c
> @@ -476,7 +476,6 @@ static int parse_action_control_slash_spaces(int *argc_p, char ***argv_p,
>  			NEXT_ARG();
>  			/* fall-through */
>  		case 0: /* fall-through */
> -		case 2:
>  			ret = parse_action_control(&argc, &argv,
>  						   result_p, allow_num);
>  			if (ret)

Applied, and removed the now unnecessary second fall-through comment.