* [bug report] perf env: Add perf_env__cpuid, perf_env__{nr_}pmu_mappings
@ 2022-02-08 11:22 Dan Carpenter
2022-02-09 15:09 ` Jiri Olsa
0 siblings, 1 reply; 3+ messages in thread
From: Dan Carpenter @ 2022-02-08 11:22 UTC (permalink / raw)
To: kim.phillips; +Cc: linux-perf-users
Hello Kim Phillips,
This is a semi-automatic email about new static checker warnings.
The patch 9fe8895a27a8: "perf env: Add perf_env__cpuid,
perf_env__{nr_}pmu_mappings" from Aug 17, 2021, leads to the
following Smatch complaint:
./tools/perf/util/env.c:476 perf_env__nr_pmu_mappings()
error: we previously assumed 'env' could be null (see line 470)
./tools/perf/util/env.c
469
470 if (!env || !env->nr_pmu_mappings) { /* Assume local operation */
^^^
Checks for NULL
471 status = perf_env__read_pmu_mappings(env);
472 if (status)
473 return 0;
474 }
475
476 return env->nr_pmu_mappings;
^^^^
Unchecked dereference
477 }
regards,
dan carpenter
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [bug report] perf env: Add perf_env__cpuid, perf_env__{nr_}pmu_mappings
2022-02-08 11:22 [bug report] perf env: Add perf_env__cpuid, perf_env__{nr_}pmu_mappings Dan Carpenter
@ 2022-02-09 15:09 ` Jiri Olsa
0 siblings, 0 replies; 3+ messages in thread
From: Jiri Olsa @ 2022-02-09 15:09 UTC (permalink / raw)
To: Dan Carpenter; +Cc: kim.phillips, linux-perf-users
On Tue, Feb 08, 2022 at 02:22:39PM +0300, Dan Carpenter wrote:
> Hello Kim Phillips,
>
> This is a semi-automatic email about new static checker warnings.
>
> The patch 9fe8895a27a8: "perf env: Add perf_env__cpuid,
> perf_env__{nr_}pmu_mappings" from Aug 17, 2021, leads to the
> following Smatch complaint:
>
> ./tools/perf/util/env.c:476 perf_env__nr_pmu_mappings()
> error: we previously assumed 'env' could be null (see line 470)
>
> ./tools/perf/util/env.c
> 469
> 470 if (!env || !env->nr_pmu_mappings) { /* Assume local operation */
> ^^^
> Checks for NULL
>
> 471 status = perf_env__read_pmu_mappings(env);
> 472 if (status)
> 473 return 0;
> 474 }
> 475
> 476 return env->nr_pmu_mappings;
> ^^^^
> Unchecked dereference
>
> 477 }
>
> regards,
> dan carpenter
I think we need to bail out for !env
jirka
---
diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
index 579e44c59914..bc30d8cd2790 100644
--- a/tools/perf/util/env.c
+++ b/tools/perf/util/env.c
@@ -467,7 +467,10 @@ int perf_env__nr_pmu_mappings(struct perf_env *env)
{
int status;
- if (!env || !env->nr_pmu_mappings) { /* Assume local operation */
+ if (!env)
+ return 0;
+
+ if (!env->nr_pmu_mappings) { /* Assume local operation */
status = perf_env__read_pmu_mappings(env);
if (status)
return 0;
@@ -480,7 +483,10 @@ const char *perf_env__pmu_mappings(struct perf_env *env)
{
int status;
- if (!env || !env->pmu_mappings) { /* Assume local operation */
+ if (!env)
+ return NULL;
+
+ if (!env->pmu_mappings) { /* Assume local operation */
status = perf_env__read_pmu_mappings(env);
if (status)
return NULL;
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [bug report] perf env: Add perf_env__cpuid, perf_env__{nr_}pmu_mappings
@ 2022-07-18 13:15 Dan Carpenter
0 siblings, 0 replies; 3+ messages in thread
From: Dan Carpenter @ 2022-07-18 13:15 UTC (permalink / raw)
To: kim.phillips; +Cc: linux-perf-users
Hello Kim Phillips,
This is a semi-automatic email about new static checker warnings.
The patch 9fe8895a27a8: "perf env: Add perf_env__cpuid,
perf_env__{nr_}pmu_mappings" from Aug 17, 2021, leads to the
following Smatch complaint:
tools/perf/util/env.c:467 perf_env__cpuid()
error: we previously assumed 'env' could be null (see line 461)
tools/perf/util/env.c
457 const char *perf_env__cpuid(struct perf_env *env)
458 {
459 int status;
460
461 if (!env || !env->cpuid) { /* Assume local operation */
462 status = perf_env__read_cpuid(env);
463 if (status)
464 return NULL;
If env is NULL and perf_env__read_cpuid() return zero then we are
toasted.
465 }
466
467 return env->cpuid;
468 }
A couple of the neighboring functions are written the same way. I'm not
sure why they don't generate checker warnings.
regards,
dan carpenter
^ permalink raw reply [flat|nested] 3+ messages in thread
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2022-02-09 15:09 ` Jiri Olsa
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