[PATCH v2 0/2] perf probe: Fix uninitialized variable

[PATCH v2 0/2] perf probe: Fix uninitialized variable

[James Clark]

Changes since V1:

 * Split into a fixes commit and tidyup
 * Pick up tags

James Clark (2):
  perf probe: Fix uninitialized variable
  perf probe: Rename err label

 tools/perf/util/probe-event.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

-- 
2.34.1

[PATCH v2 1/2] perf probe: Fix uninitialized variable

[James Clark]

Since the linked fixes: commit, err is returned uninitialized due to the
removal of "return 0". Initialize err to fix it.

This fixes the following intermittent test failure on release builds:

 $ perf test "testsuite_probe"
 ...
 -- [ FAIL ] -- perf_probe :: test_invalid_options :: mutually exclusive options :: -L foo -V bar (output regexp parsing)
 Regexp not found: \"Error: switch .+ cannot be used with switch .+\"
 ...

Fixes: 080e47b2a237 ("perf probe: Introduce quotation marks support")
Tested-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: James Clark <james.clark@linaro.org>
---
 tools/perf/util/probe-event.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 6d51a4c98ad7..eaa0318e9b87 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -1370,7 +1370,7 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
 {
 	char *buf = strdup(arg);
 	char *p;
-	int err;
+	int err = 0;
 
 	if (!buf)
 		return -ENOMEM;
-- 
2.34.1

[PATCH v2 2/2] perf probe: Rename err label

[James Clark]

Rename err to out to avoid confusion because buf is still supposed to be
freed in non error cases.

Tested-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: James Clark <james.clark@linaro.org>
---
 tools/perf/util/probe-event.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index eaa0318e9b87..35af6570cf9b 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -1383,20 +1383,20 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
 		if (p == buf) {
 			semantic_error("No file/function name in '%s'.\n", p);
 			err = -EINVAL;
-			goto err;
+			goto out;
 		}
 		*(p++) = '\0';
 
 		err = parse_line_num(&p, &lr->start, "start line");
 		if (err)
-			goto err;
+			goto out;
 
 		if (*p == '+' || *p == '-') {
 			const char c = *(p++);
 
 			err = parse_line_num(&p, &lr->end, "end line");
 			if (err)
-				goto err;
+				goto out;
 
 			if (c == '+') {
 				lr->end += lr->start;
@@ -1416,11 +1416,11 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
 		if (lr->start > lr->end) {
 			semantic_error("Start line must be smaller"
 				       " than end line.\n");
-			goto err;
+			goto out;
 		}
 		if (*p != '\0') {
 			semantic_error("Tailing with invalid str '%s'.\n", p);
-			goto err;
+			goto out;
 		}
 	}
 
@@ -1431,7 +1431,7 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
 			lr->file = strdup_esq(p);
 			if (lr->file == NULL) {
 				err = -ENOMEM;
-				goto err;
+				goto out;
 			}
 		}
 		if (*buf != '\0')
@@ -1439,7 +1439,7 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
 		if (!lr->function && !lr->file) {
 			semantic_error("Only '@*' is not allowed.\n");
 			err = -EINVAL;
-			goto err;
+			goto out;
 		}
 	} else if (strpbrk_esq(buf, "/."))
 		lr->file = strdup_esq(buf);
@@ -1448,10 +1448,10 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
 	else {	/* Invalid name */
 		semantic_error("'%s' is not a valid function name.\n", buf);
 		err = -EINVAL;
-		goto err;
+		goto out;
 	}
 
-err:
+out:
 	free(buf);
 	return err;
 }
-- 
2.34.1

Re: [PATCH v2 1/2] perf probe: Fix uninitialized variable

[Arnaldo Carvalho de Melo]

On Wed, Dec 11, 2024 at 08:55:23AM +0000, James Clark wrote:
> Since the linked fixes: commit, err is returned uninitialized due to the
> removal of "return 0". Initialize err to fix it.
> 
> This fixes the following intermittent test failure on release builds:
> 
>  $ perf test "testsuite_probe"
>  ...
>  -- [ FAIL ] -- perf_probe :: test_invalid_options :: mutually exclusive options :: -L foo -V bar (output regexp parsing)
>  Regexp not found: \"Error: switch .+ cannot be used with switch .+\"
>  ...

So Namhyung, this one should go to perf-tools, I can pick the second on
perf-tools-next, so that we keep perf-tools as small as possible.

- Arnaldo
 
> Fixes: 080e47b2a237 ("perf probe: Introduce quotation marks support")
> Tested-by: Namhyung Kim <namhyung@kernel.org>
> Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> Signed-off-by: James Clark <james.clark@linaro.org>
> ---
>  tools/perf/util/probe-event.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index 6d51a4c98ad7..eaa0318e9b87 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -1370,7 +1370,7 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
>  {
>  	char *buf = strdup(arg);
>  	char *p;
> -	int err;
> +	int err = 0;
>  
>  	if (!buf)
>  		return -ENOMEM;
> -- 
> 2.34.1

Re: [PATCH v2 1/2] perf probe: Fix uninitialized variable

[Namhyung Kim]

Hello,

On Wed, Dec 11, 2024 at 10:15:30AM -0300, Arnaldo Carvalho de Melo wrote:
> On Wed, Dec 11, 2024 at 08:55:23AM +0000, James Clark wrote:
> > Since the linked fixes: commit, err is returned uninitialized due to the
> > removal of "return 0". Initialize err to fix it.
> > 
> > This fixes the following intermittent test failure on release builds:
> > 
> >  $ perf test "testsuite_probe"
> >  ...
> >  -- [ FAIL ] -- perf_probe :: test_invalid_options :: mutually exclusive options :: -L foo -V bar (output regexp parsing)
> >  Regexp not found: \"Error: switch .+ cannot be used with switch .+\"
> >  ...
> 
> So Namhyung, this one should go to perf-tools, I can pick the second on
> perf-tools-next, so that we keep perf-tools as small as possible.

Sure, will replace and force-push.

Thanks,
Namhyung

Re: [PATCH v2 1/2] perf probe: Fix uninitialized variable

[Namhyung Kim]

On Wed, Dec 11, 2024 at 09:18:45AM -0800, Namhyung Kim wrote:
> Hello,
> 
> On Wed, Dec 11, 2024 at 10:15:30AM -0300, Arnaldo Carvalho de Melo wrote:
> > On Wed, Dec 11, 2024 at 08:55:23AM +0000, James Clark wrote:
> > > Since the linked fixes: commit, err is returned uninitialized due to the
> > > removal of "return 0". Initialize err to fix it.
> > > 
> > > This fixes the following intermittent test failure on release builds:
> > > 
> > >  $ perf test "testsuite_probe"
> > >  ...
> > >  -- [ FAIL ] -- perf_probe :: test_invalid_options :: mutually exclusive options :: -L foo -V bar (output regexp parsing)
> > >  Regexp not found: \"Error: switch .+ cannot be used with switch .+\"
> > >  ...
> > 
> > So Namhyung, this one should go to perf-tools, I can pick the second on
> > perf-tools-next, so that we keep perf-tools as small as possible.
> 
> Sure, will replace and force-push.

Applied patch 1 to perf-tools, thanks!

Best regards,
Namhyung

Re: [PATCH v2 2/2] perf probe: Rename err label

[Arnaldo Carvalho de Melo]

On Wed, Dec 11, 2024 at 08:55:24AM +0000, James Clark wrote:
> Rename err to out to avoid confusion because buf is still supposed to be
> freed in non error cases.

Thanks, applied to perf-tools-next,

- Arnaldo
 
> Tested-by: Namhyung Kim <namhyung@kernel.org>
> Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> Signed-off-by: James Clark <james.clark@linaro.org>
> ---
>  tools/perf/util/probe-event.c | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)
> 
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index eaa0318e9b87..35af6570cf9b 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -1383,20 +1383,20 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
>  		if (p == buf) {
>  			semantic_error("No file/function name in '%s'.\n", p);
>  			err = -EINVAL;
> -			goto err;
> +			goto out;
>  		}
>  		*(p++) = '\0';
>  
>  		err = parse_line_num(&p, &lr->start, "start line");
>  		if (err)
> -			goto err;
> +			goto out;
>  
>  		if (*p == '+' || *p == '-') {
>  			const char c = *(p++);
>  
>  			err = parse_line_num(&p, &lr->end, "end line");
>  			if (err)
> -				goto err;
> +				goto out;
>  
>  			if (c == '+') {
>  				lr->end += lr->start;
> @@ -1416,11 +1416,11 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
>  		if (lr->start > lr->end) {
>  			semantic_error("Start line must be smaller"
>  				       " than end line.\n");
> -			goto err;
> +			goto out;
>  		}
>  		if (*p != '\0') {
>  			semantic_error("Tailing with invalid str '%s'.\n", p);
> -			goto err;
> +			goto out;
>  		}
>  	}
>  
> @@ -1431,7 +1431,7 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
>  			lr->file = strdup_esq(p);
>  			if (lr->file == NULL) {
>  				err = -ENOMEM;
> -				goto err;
> +				goto out;
>  			}
>  		}
>  		if (*buf != '\0')
> @@ -1439,7 +1439,7 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
>  		if (!lr->function && !lr->file) {
>  			semantic_error("Only '@*' is not allowed.\n");
>  			err = -EINVAL;
> -			goto err;
> +			goto out;
>  		}
>  	} else if (strpbrk_esq(buf, "/."))
>  		lr->file = strdup_esq(buf);
> @@ -1448,10 +1448,10 @@ int parse_line_range_desc(const char *arg, struct line_range *lr)
>  	else {	/* Invalid name */
>  		semantic_error("'%s' is not a valid function name.\n", buf);
>  		err = -EINVAL;
> -		goto err;
> +		goto out;
>  	}
>  
> -err:
> +out:
>  	free(buf);
>  	return err;
>  }
> -- 
> 2.34.1
>