[PATCH] perf iostat: Release the port list if command allocation fails

[PATCH] perf iostat: Release the port list if command allocation fails

[lirongqing]

From: Li RongQing <lirongqing@baidu.com>

The event-group builder takes ownership of the root port list and frees
it on its normal and parsing-error paths. If allocation of the event
command fails, however, it returns directly without releasing the list,
its pointer array or its ports.

Use the existing cleanup path for this allocation failure too, before
any port has been transferred to an event.

Found while testing the iostat fixes with allocation fault injection.

Fixes: f9ed693e8bc0 ("perf stat: Enable iostat mode for x86 platforms")
Signed-off-by: Li RongQing <lirongqing@baidu.com>
---
 tools/perf/arch/x86/util/iostat.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/perf/arch/x86/util/iostat.c b/tools/perf/arch/x86/util/iostat.c
index 2dc5ac6..f8b4939 100644
--- a/tools/perf/arch/x86/util/iostat.c
+++ b/tools/perf/arch/x86/util/iostat.c
@@ -342,8 +342,10 @@ static int iostat_event_group(struct evlist *evl,
 	struct perf_cpu cpu;
 	unsigned int cpu_map_idx;
 
-	if (!iostat_cmd)
-		return -ENOMEM;
+	if (!iostat_cmd) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
 	for (idx = 0; idx < list->nr_entries; idx++) {
 		sprintf(iostat_cmd, iostat_cmd_template,
-- 
2.9.4

Re: [PATCH] perf iostat: Release the port list if command allocation fails

[Namhyung Kim]

Hello,

On Fri, Nov 06, 2026 at 10:18:40AM +0800, lirongqing wrote:
> From: Li RongQing <lirongqing@baidu.com>
> 
> The event-group builder takes ownership of the root port list and frees
> it on its normal and parsing-error paths. If allocation of the event
> command fails, however, it returns directly without releasing the list,
> its pointer array or its ports.
> 
> Use the existing cleanup path for this allocation failure too, before
> any port has been transferred to an event.
> 
> Found while testing the iostat fixes with allocation fault injection.
> 
> Fixes: f9ed693e8bc0 ("perf stat: Enable iostat mode for x86 platforms")
> Signed-off-by: Li RongQing <lirongqing@baidu.com>

This patch doesn't apply.  Can you please rebase onto the current
perf-tools-next?

Thanks,
Namhyung

> ---
>  tools/perf/arch/x86/util/iostat.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/arch/x86/util/iostat.c b/tools/perf/arch/x86/util/iostat.c
> index 2dc5ac6..f8b4939 100644
> --- a/tools/perf/arch/x86/util/iostat.c
> +++ b/tools/perf/arch/x86/util/iostat.c
> @@ -342,8 +342,10 @@ static int iostat_event_group(struct evlist *evl,
>  	struct perf_cpu cpu;
>  	unsigned int cpu_map_idx;
>  
> -	if (!iostat_cmd)
> -		return -ENOMEM;
> +	if (!iostat_cmd) {
> +		ret = -ENOMEM;
> +		goto err;
> +	}
>  
>  	for (idx = 0; idx < list->nr_entries; idx++) {
>  		sprintf(iostat_cmd, iostat_cmd_template,
> -- 
> 2.9.4
>