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[PATCH v1] perf hwmon_pmu: Ensure hwmon key union is zeroed before use

Ian Rogers posted 1 patch 1 year, 2 months ago 
tools/perf/util/hwmon_pmu.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
[PATCH v1] perf hwmon_pmu: Ensure hwmon key union is zeroed before use
Posted by Ian Rogers 1 year, 2 months ago 
Non-zero values led to mismatches in testing. This was reproducible
with -fsanitize=undefined.

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Closes: https://lore.kernel.org/lkml/Zzdtj0PEWEX3ATwL@x1/
Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/util/hwmon_pmu.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/hwmon_pmu.c b/tools/perf/util/hwmon_pmu.c
index ac2245acdc6d..4d9d6f405434 100644
--- a/tools/perf/util/hwmon_pmu.c
+++ b/tools/perf/util/hwmon_pmu.c
@@ -274,7 +274,7 @@ static int hwmon_pmu__read_events(struct hwmon_pmu *pmu)
 		int number;
 		enum hwmon_item item;
 		bool alarm;
-		union hwmon_pmu_event_key key = {};
+		union hwmon_pmu_event_key key = { .type_and_num = 0 };
 		struct hwmon_pmu_event_value *value;
 
 		if (ent->d_type != DT_REG)
@@ -560,7 +560,7 @@ bool hwmon_pmu__have_event(struct perf_pmu *pmu, const char *name)
 	struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
 	enum hwmon_type type;
 	int number;
-	union hwmon_pmu_event_key key = {};
+	union hwmon_pmu_event_key key = { .type_and_num = 0 };
 	struct hashmap_entry *cur;
 	size_t bkt;
 
@@ -623,10 +623,11 @@ static int hwmon_pmu__config_term(const struct hwmon_pmu *hwm,
 					return -EINVAL;
 			} else {
 				union hwmon_pmu_event_key key = {
-					.type = type,
-					.num = number,
+					.type_and_num = 0,
 				};
 
+				key.type = type;
+				key.num = number;
 				attr->config = key.type_and_num;
 			}
 			return 0;
-- 
2.47.0.371.ga323438b13-goog
Re: [PATCH v1] perf hwmon_pmu: Ensure hwmon key union is zeroed before use
Posted by Namhyung Kim 1 year, 2 months ago 
On Tue, 19 Nov 2024 15:00:33 -0800, Ian Rogers wrote:

> Non-zero values led to mismatches in testing. This was reproducible
> with -fsanitize=undefined.
> 
> 

Applied to perf-tools-next, thanks!

Best regards,
Namhyung
Re: [PATCH v1] perf hwmon_pmu: Ensure hwmon key union is zeroed before use
Posted by Namhyung Kim 1 year, 2 months ago 
On Tue, Nov 19, 2024 at 03:00:33PM -0800, Ian Rogers wrote:
> Non-zero values led to mismatches in testing. This was reproducible
> with -fsanitize=undefined.

It's sad the compiler didn't initialize all the members if it has
members with different size.

> 
> Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
> Closes: https://lore.kernel.org/lkml/Zzdtj0PEWEX3ATwL@x1/
> Signed-off-by: Ian Rogers <irogers@google.com>

Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks,
Namhyung

> ---
>  tools/perf/util/hwmon_pmu.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/perf/util/hwmon_pmu.c b/tools/perf/util/hwmon_pmu.c
> index ac2245acdc6d..4d9d6f405434 100644
> --- a/tools/perf/util/hwmon_pmu.c
> +++ b/tools/perf/util/hwmon_pmu.c
> @@ -274,7 +274,7 @@ static int hwmon_pmu__read_events(struct hwmon_pmu *pmu)
>  		int number;
>  		enum hwmon_item item;
>  		bool alarm;
> -		union hwmon_pmu_event_key key = {};
> +		union hwmon_pmu_event_key key = { .type_and_num = 0 };
>  		struct hwmon_pmu_event_value *value;
>  
>  		if (ent->d_type != DT_REG)
> @@ -560,7 +560,7 @@ bool hwmon_pmu__have_event(struct perf_pmu *pmu, const char *name)
>  	struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
>  	enum hwmon_type type;
>  	int number;
> -	union hwmon_pmu_event_key key = {};
> +	union hwmon_pmu_event_key key = { .type_and_num = 0 };
>  	struct hashmap_entry *cur;
>  	size_t bkt;
>  
> @@ -623,10 +623,11 @@ static int hwmon_pmu__config_term(const struct hwmon_pmu *hwm,
>  					return -EINVAL;
>  			} else {
>  				union hwmon_pmu_event_key key = {
> -					.type = type,
> -					.num = number,
> +					.type_and_num = 0,
>  				};
>  
> +				key.type = type;
> +				key.num = number;
>  				attr->config = key.type_and_num;
>  			}
>  			return 0;
> -- 
> 2.47.0.371.ga323438b13-goog
>
Re: [PATCH v1] perf hwmon_pmu: Ensure hwmon key union is zeroed before use
Posted by Arnaldo Carvalho de Melo 1 year, 2 months ago 
On Tue, Nov 19, 2024 at 03:00:33PM -0800, Ian Rogers wrote:
> Non-zero values led to mismatches in testing. This was reproducible
> with -fsanitize=undefined.

Unfortunately, not yet, see below, I'll have some meetings and will try
to get back at this, to try and take advantage I went thru the code
yesterday.

- Arnaldo

⬢ [acme@toolbox perf-tools-next]$ git log --oneline -5
9ae6c7a4bd02acbd (HEAD -> perf-tools-next) perf hwmon_pmu: Ensure hwmon key union is zeroed before use
3e37de098af38179 perf tests hwmon_pmu: Remove double evlist__delete()
0565017a0ac824c2 perf test: Correct hwmon test PMU detection
85c60a01b85ee956 (perf-tools-next/tmp.perf-tools-next, perf-tools-next/perf-tools-next, perf-tools-next.korg/tmp.perf-tools-next, perf-tools-next.korg/perf-tools-next, acme/tmp.perf-tools-next, acme/perf-tools-next, acme.korg/tmp.perf-tools-next, acme.korg/perf-tools-next) perf: Remove unused del_perf_probe_events()
8f997865ee9e7328 perf pmu: Move pmu_metrics_table__find and remove ARM override
⬢ [acme@toolbox perf-tools-next]$

⬢ [acme@toolbox perf-tools-next]$ perf test 11
 11: Hwmon PMU                                                       :
 11.1: Basic parsing test                                            : Ok
 11.2: Parsing without PMU name                                      : FAILED!
 11.3: Parsing with PMU name                                         : FAILED!
⬢ [acme@toolbox perf-tools-next]$ perf -v
perf version 6.12.rc6.g9ae6c7a4bd02
⬢ [acme@toolbox perf-tools-next]$

root@x1:~# perf -vv
perf version 6.12.rc6.g9ae6c7a4bd02
                   aio: [ on  ]  # HAVE_AIO_SUPPORT
                   bpf: [ on  ]  # HAVE_LIBBPF_SUPPORT
         bpf_skeletons: [ on  ]  # HAVE_BPF_SKEL
            debuginfod: [ on  ]  # HAVE_DEBUGINFOD_SUPPORT
                 dwarf: [ on  ]  # HAVE_LIBDW_SUPPORT
    dwarf_getlocations: [ on  ]  # HAVE_LIBDW_SUPPORT
          dwarf-unwind: [ on  ]  # HAVE_DWARF_UNWIND_SUPPORT
              auxtrace: [ on  ]  # HAVE_AUXTRACE_SUPPORT
              libaudit: [ OFF ]  # HAVE_LIBAUDIT_SUPPORT
                libbfd: [ OFF ]  # HAVE_LIBBFD_SUPPORT
           libcapstone: [ on  ]  # HAVE_LIBCAPSTONE_SUPPORT
             libcrypto: [ on  ]  # HAVE_LIBCRYPTO_SUPPORT
    libdw-dwarf-unwind: [ on  ]  # HAVE_LIBDW_SUPPORT
                libelf: [ on  ]  # HAVE_LIBELF_SUPPORT
               libnuma: [ on  ]  # HAVE_LIBNUMA_SUPPORT
            libopencsd: [ on  ]  # HAVE_CSTRACE_SUPPORT
               libperl: [ on  ]  # HAVE_LIBPERL_SUPPORT
               libpfm4: [ on  ]  # HAVE_LIBPFM
             libpython: [ on  ]  # HAVE_LIBPYTHON_SUPPORT
              libslang: [ on  ]  # HAVE_SLANG_SUPPORT
         libtraceevent: [ on  ]  # HAVE_LIBTRACEEVENT
             libunwind: [ OFF ]  # HAVE_LIBUNWIND_SUPPORT
                  lzma: [ on  ]  # HAVE_LZMA_SUPPORT
numa_num_possible_cpus: [ on  ]  # HAVE_LIBNUMA_SUPPORT
         syscall_table: [ on  ]  # HAVE_SYSCALL_TABLE_SUPPORT
                  zlib: [ on  ]  # HAVE_ZLIB_SUPPORT
                  zstd: [ on  ]  # HAVE_ZSTD_SUPPORT
root@x1:~# perf test 11
 11: Hwmon PMU                                                       :
 11.1: Basic parsing test                                            : Ok
 11.2: Parsing without PMU name                                      : FAILED!
 11.3: Parsing with PMU name                                         : FAILED!
root@x1:~# perf test -vv 11
 11: Hwmon PMU                                                       :
 11.1: Basic parsing test:
--- start ---
test child forked, pid 152385
hwmon_pmu: not a hwmon type 'badtype' in file name 'badtype5_baditem'
hwmon_pmu: not a hwmon item 'baditem' in file name 'humidity6_baditem'
---- end(0) ----
 11.1: Basic parsing test                                            : Ok
 11.2: Parsing without PMU name:
--- start ---
test child forked, pid 152386
Testing 'temp_test_hwmon_event1'
Using CPUID GenuineIntel-6-BA-3
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'pwm1'
Not a hwmon file 'pwm1'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: removing event 'pwm1' that has no input file
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
FAILED tests/hwmon_pmu.c:158 failed to parse event 'temp_test_hwmon_event1', err 1
event syntax error: 'temp_test_hwmon_event1'
                     \___ Bad event name

Unable to find event on a PMU of 'temp_test_hwmon_event1'
---- end(-1) ----
 11.2: Parsing without PMU name                                      : FAILED!
 11.3: Parsing with PMU name:
--- start ---
test child forked, pid 152387
Testing 'temp_test_hwmon_event1'
Using CPUID GenuineIntel-6-BA-3
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'pwm1'
Not a hwmon file 'pwm1'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: removing event 'pwm1' that has no input file
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
hwmon_pmu: not a hwmon file 'uevent'
Not a hwmon file 'uevent'
hwmon_pmu: not a hwmon file 'name'
Not a hwmon file 'name'
FAILED tests/hwmon_pmu.c:158 failed to parse event 'temp_test_hwmon_event1', err 1
event syntax error: 'temp_test_hwmon_event1'
                     \___ Bad event name

Unable to find event on a PMU of 'temp_test_hwmon_event1'
---- end(-1) ----
 11.3: Parsing with PMU name                                         : FAILED!
root@x1:~#
 
> Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
> Closes: https://lore.kernel.org/lkml/Zzdtj0PEWEX3ATwL@x1/
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tools/perf/util/hwmon_pmu.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/perf/util/hwmon_pmu.c b/tools/perf/util/hwmon_pmu.c
> index ac2245acdc6d..4d9d6f405434 100644
> --- a/tools/perf/util/hwmon_pmu.c
> +++ b/tools/perf/util/hwmon_pmu.c
> @@ -274,7 +274,7 @@ static int hwmon_pmu__read_events(struct hwmon_pmu *pmu)
>  		int number;
>  		enum hwmon_item item;
>  		bool alarm;
> -		union hwmon_pmu_event_key key = {};
> +		union hwmon_pmu_event_key key = { .type_and_num = 0 };
>  		struct hwmon_pmu_event_value *value;
>  
>  		if (ent->d_type != DT_REG)
> @@ -560,7 +560,7 @@ bool hwmon_pmu__have_event(struct perf_pmu *pmu, const char *name)
>  	struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
>  	enum hwmon_type type;
>  	int number;
> -	union hwmon_pmu_event_key key = {};
> +	union hwmon_pmu_event_key key = { .type_and_num = 0 };
>  	struct hashmap_entry *cur;
>  	size_t bkt;
>  
> @@ -623,10 +623,11 @@ static int hwmon_pmu__config_term(const struct hwmon_pmu *hwm,
>  					return -EINVAL;
>  			} else {
>  				union hwmon_pmu_event_key key = {
> -					.type = type,
> -					.num = number,
> +					.type_and_num = 0,
>  				};
>  
> +				key.type = type;
> +				key.num = number;
>  				attr->config = key.type_and_num;
>  			}
>  			return 0;
> -- 
> 2.47.0.371.ga323438b13-goog
>

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