[PATCH -next] tools build: Check return value of fwrite_unlocked in jvmti_agent.c

[PATCH -next] tools build: Check return value of fwrite_unlocked in jvmti_agent.c

[Wang ShaoBo]

Function jvmti_write_code called by compiled_method_load_cb may return
error in using fwrite_unlocked, this failure should be captured and
warned.

Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
---
 tools/perf/jvmti/jvmti_agent.c | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/tools/perf/jvmti/jvmti_agent.c b/tools/perf/jvmti/jvmti_agent.c
index 88108598d6e9..a1fe6aa16b6d 100644
--- a/tools/perf/jvmti/jvmti_agent.c
+++ b/tools/perf/jvmti/jvmti_agent.c
@@ -363,7 +363,7 @@ jvmti_write_code(void *agent, char const *sym,
 	struct jr_code_load rec;
 	size_t sym_len;
 	FILE *fp = agent;
-	int ret = -1;
+	int ret;
 
 	/* don't care about 0 length function, no samples */
 	if (size == 0)
@@ -401,16 +401,23 @@ jvmti_write_code(void *agent, char const *sym,
 	rec.code_index = code_generation++;
 
 	ret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
-	fwrite_unlocked(sym, sym_len, 1, fp);
+	if (ret)
+		goto error;
+	ret = fwrite_unlocked(sym, sym_len, 1, fp);
+	if (ret)
+		goto error;
 
-	if (code)
-		fwrite_unlocked(code, size, 1, fp);
+	if (code) {
+		ret = fwrite_unlocked(code, size, 1, fp);
+		if (ret)
+			goto error;
+	}
 
 	funlockfile(fp);
-
-	ret = 0;
-
-	return ret;
+	return 0;
+error:
+	funlockfile(fp);
+	return -1;
 }
 
 int
-- 
2.17.1

Re: [PATCH -next] tools build: Check return value of fwrite_unlocked in jvmti_agent.c

[Arnaldo Carvalho de Melo]

Em Fri, Jul 24, 2020 at 06:07:06PM +0800, Wang ShaoBo escreveu:
> Function jvmti_write_code called by compiled_method_load_cb may return
> error in using fwrite_unlocked, this failure should be captured and
> warned.

Thanks, applied.

- Arnaldo
 
> Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
> ---
>  tools/perf/jvmti/jvmti_agent.c | 23 +++++++++++++++--------
>  1 file changed, 15 insertions(+), 8 deletions(-)
> 
> diff --git a/tools/perf/jvmti/jvmti_agent.c b/tools/perf/jvmti/jvmti_agent.c
> index 88108598d6e9..a1fe6aa16b6d 100644
> --- a/tools/perf/jvmti/jvmti_agent.c
> +++ b/tools/perf/jvmti/jvmti_agent.c
> @@ -363,7 +363,7 @@ jvmti_write_code(void *agent, char const *sym,
>  	struct jr_code_load rec;
>  	size_t sym_len;
>  	FILE *fp = agent;
> -	int ret = -1;
> +	int ret;
>  
>  	/* don't care about 0 length function, no samples */
>  	if (size == 0)
> @@ -401,16 +401,23 @@ jvmti_write_code(void *agent, char const *sym,
>  	rec.code_index = code_generation++;
>  
>  	ret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
> -	fwrite_unlocked(sym, sym_len, 1, fp);
> +	if (ret)
> +		goto error;
> +	ret = fwrite_unlocked(sym, sym_len, 1, fp);
> +	if (ret)
> +		goto error;
>  
> -	if (code)
> -		fwrite_unlocked(code, size, 1, fp);
> +	if (code) {
> +		ret = fwrite_unlocked(code, size, 1, fp);
> +		if (ret)
> +			goto error;
> +	}
>  
>  	funlockfile(fp);
> -
> -	ret = 0;
> -
> -	return ret;
> +	return 0;
> +error:
> +	funlockfile(fp);
> +	return -1;
>  }
>  
>  int
> -- 
> 2.17.1
> 

-- 

- Arnaldo

Re: [PATCH -next] tools build: Check return value of fwrite_unlocked in jvmti_agent.c

[Ian Rogers]

On Fri, Jul 24, 2020 at 3:07 AM Wang ShaoBo <bobo.shaobowang@huawei.com> wrote:
>
> Function jvmti_write_code called by compiled_method_load_cb may return
> error in using fwrite_unlocked, this failure should be captured and
> warned.
>
> Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
> ---
>  tools/perf/jvmti/jvmti_agent.c | 23 +++++++++++++++--------
>  1 file changed, 15 insertions(+), 8 deletions(-)
>
> diff --git a/tools/perf/jvmti/jvmti_agent.c b/tools/perf/jvmti/jvmti_agent.c
> index 88108598d6e9..a1fe6aa16b6d 100644
> --- a/tools/perf/jvmti/jvmti_agent.c
> +++ b/tools/perf/jvmti/jvmti_agent.c
> @@ -363,7 +363,7 @@ jvmti_write_code(void *agent, char const *sym,
>         struct jr_code_load rec;
>         size_t sym_len;
>         FILE *fp = agent;
> -       int ret = -1;
> +       int ret;
>
>         /* don't care about 0 length function, no samples */
>         if (size == 0)
> @@ -401,16 +401,23 @@ jvmti_write_code(void *agent, char const *sym,
>         rec.code_index = code_generation++;
>
>         ret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
> -       fwrite_unlocked(sym, sym_len, 1, fp);
> +       if (ret)
> +               goto error;

Sorry, it seems I lost a reply to this. Won't ret here be the number
of items written and not an error code? Consequently all writes will
immediately goto error?

Thanks,
Ian

> +       ret = fwrite_unlocked(sym, sym_len, 1, fp);
> +       if (ret)
> +               goto error;
>
> -       if (code)
> -               fwrite_unlocked(code, size, 1, fp);
> +       if (code) {
> +               ret = fwrite_unlocked(code, size, 1, fp);
> +               if (ret)
> +                       goto error;
> +       }
>
>         funlockfile(fp);
> -
> -       ret = 0;
> -
> -       return ret;
> +       return 0;
> +error:
> +       funlockfile(fp);
> +       return -1;
>  }
>
>  int
> --
> 2.17.1
>

Re: [PATCH -next] tools build: Check return value of fwrite_unlocked in jvmti_agent.c

[Arnaldo Carvalho de Melo]

On July 29, 2020 8:47:36 PM GMT-03:00, Ian Rogers <irogers@google.com> wrote:
>On Fri, Jul 24, 2020 at 3:07 AM Wang ShaoBo
><bobo.shaobowang@huawei.com> wrote:
>>
>> Function jvmti_write_code called by compiled_method_load_cb may
>return
>> error in using fwrite_unlocked, this failure should be captured and
>> warned.
>>
>> Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
>> ---
>>  tools/perf/jvmti/jvmti_agent.c | 23 +++++++++++++++--------
>>  1 file changed, 15 insertions(+), 8 deletions(-)
>>
>> diff --git a/tools/perf/jvmti/jvmti_agent.c
>b/tools/perf/jvmti/jvmti_agent.c
>> index 88108598d6e9..a1fe6aa16b6d 100644
>> --- a/tools/perf/jvmti/jvmti_agent.c
>> +++ b/tools/perf/jvmti/jvmti_agent.c
>> @@ -363,7 +363,7 @@ jvmti_write_code(void *agent, char const *sym,
>>         struct jr_code_load rec;
>>         size_t sym_len;
>>         FILE *fp = agent;
>> -       int ret = -1;
>> +       int ret;
>>
>>         /* don't care about 0 length function, no samples */
>>         if (size == 0)
>> @@ -401,16 +401,23 @@ jvmti_write_code(void *agent, char const *sym,
>>         rec.code_index = code_generation++;
>>
>>         ret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
>> -       fwrite_unlocked(sym, sym_len, 1, fp);
>> +       if (ret)
>> +               goto error;
>
>Sorry, it seems I lost a reply to this. Won't ret here be the number
>of items written and not an error code? Consequently all writes will
>immediately goto error?

Good thing this is in tmp.perf/core, you're right, the test has to be (ret < 0)... I'll fix, thanks!

Also we need some 'perf test' for this :-/

- Arnaldo
>
>Thanks,
>Ian
>
>> +       ret = fwrite_unlocked(sym, sym_len, 1, fp);
>> +       if (ret)
>> +               goto error;
>>
>> -       if (code)
>> -               fwrite_unlocked(code, size, 1, fp);
>> +       if (code) {
>> +               ret = fwrite_unlocked(code, size, 1, fp);
>> +               if (ret)
>> +                       goto error;
>> +       }
>>
>>         funlockfile(fp);
>> -
>> -       ret = 0;
>> -
>> -       return ret;
>> +       return 0;
>> +error:
>> +       funlockfile(fp);
>> +       return -1;
>>  }
>>
>>  int
>> --
>> 2.17.1
>>

-- 
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Re: [PATCH -next] tools build: Check return value of fwrite_unlocked in jvmti_agent.c

[Arnaldo Carvalho de Melo]

Em Wed, Jul 29, 2020 at 04:47:36PM -0700, Ian Rogers escreveu:
> On Fri, Jul 24, 2020 at 3:07 AM Wang ShaoBo <bobo.shaobowang@huawei.com> wrote:
> >
> > Function jvmti_write_code called by compiled_method_load_cb may return
> > error in using fwrite_unlocked, this failure should be captured and
> > warned.
> >
> > Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
> > ---
> >  tools/perf/jvmti/jvmti_agent.c | 23 +++++++++++++++--------
> >  1 file changed, 15 insertions(+), 8 deletions(-)
> >
> > diff --git a/tools/perf/jvmti/jvmti_agent.c b/tools/perf/jvmti/jvmti_agent.c
> > index 88108598d6e9..a1fe6aa16b6d 100644
> > --- a/tools/perf/jvmti/jvmti_agent.c
> > +++ b/tools/perf/jvmti/jvmti_agent.c
> > @@ -363,7 +363,7 @@ jvmti_write_code(void *agent, char const *sym,
> >         struct jr_code_load rec;
> >         size_t sym_len;
> >         FILE *fp = agent;
> > -       int ret = -1;
> > +       int ret;
> >
> >         /* don't care about 0 length function, no samples */
> >         if (size == 0)
> > @@ -401,16 +401,23 @@ jvmti_write_code(void *agent, char const *sym,
> >         rec.code_index = code_generation++;
> >
> >         ret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
> > -       fwrite_unlocked(sym, sym_len, 1, fp);
> > +       if (ret)
> > +               goto error;
> 
> Sorry, it seems I lost a reply to this. Won't ret here be the number
> of items written and not an error code? Consequently all writes will
> immediately goto error?

Yeah, I removed it from tmp.perf/core.

Wang, please address Ian review, and consider having just one out exit
label.

- Arnaldo
 
> Thanks,
> Ian
> 
> > +       ret = fwrite_unlocked(sym, sym_len, 1, fp);
> > +       if (ret)
> > +               goto error;
> >
> > -       if (code)
> > -               fwrite_unlocked(code, size, 1, fp);
> > +       if (code) {
> > +               ret = fwrite_unlocked(code, size, 1, fp);
> > +               if (ret)
> > +                       goto error;
> > +       }
> >
> >         funlockfile(fp);
> > -
> > -       ret = 0;
> > -
> > -       return ret;
> > +       return 0;
> > +error:
> > +       funlockfile(fp);
> > +       return -1;
> >  }
> >
> >  int
> > --
> > 2.17.1
> >

-- 

- Arnaldo

Re: [PATCH -next] tools build: Check return value of fwrite_unlocked in jvmti_agent.c

[Wangshaobo (bobo)]

在 2020/7/30 18:03, Arnaldo Carvalho de Melo 写道:
> Em Wed, Jul 29, 2020 at 04:47:36PM -0700, Ian Rogers escreveu:
>> On Fri, Jul 24, 2020 at 3:07 AM Wang ShaoBo <bobo.shaobowang@huawei.com> wrote:
>>> Function jvmti_write_code called by compiled_method_load_cb may return
>>> error in using fwrite_unlocked, this failure should be captured and
>>> warned.
>>>
>>> Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
>>> ---
>>>   tools/perf/jvmti/jvmti_agent.c | 23 +++++++++++++++--------
>>>   1 file changed, 15 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/tools/perf/jvmti/jvmti_agent.c b/tools/perf/jvmti/jvmti_agent.c
>>> index 88108598d6e9..a1fe6aa16b6d 100644
>>> --- a/tools/perf/jvmti/jvmti_agent.c
>>> +++ b/tools/perf/jvmti/jvmti_agent.c
>>> @@ -363,7 +363,7 @@ jvmti_write_code(void *agent, char const *sym,
>>>          struct jr_code_load rec;
>>>          size_t sym_len;
>>>          FILE *fp = agent;
>>> -       int ret = -1;
>>> +       int ret;
>>>
>>>          /* don't care about 0 length function, no samples */
>>>          if (size == 0)
>>> @@ -401,16 +401,23 @@ jvmti_write_code(void *agent, char const *sym,
>>>          rec.code_index = code_generation++;
>>>
>>>          ret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
>>> -       fwrite_unlocked(sym, sym_len, 1, fp);
>>> +       if (ret)
>>> +               goto error;
>> Sorry, it seems I lost a reply to this. Won't ret here be the number
>> of items written and not an error code? Consequently all writes will
>> immediately goto error?
> Yeah, I removed it from tmp.perf/core.
>
> Wang, please address Ian review, and consider having just one out exit
> label.
>
> - Arnaldo
>   

I am sorry I forgot what does fwrite_unlocked return, as same as fwrite 
error happens,

the return val is a short item count (or zero)  but not equals the items 
written. I have fixed

it and already sent v2 and address Ian review, thanks a lot.

... and i refer to the writing of function jvmti_write_debug_info() for 
giving out exit label,

thanks again,

- Wang ShaoBo

>> Thanks,
>> Ian
>>
>>> +       ret = fwrite_unlocked(sym, sym_len, 1, fp);
>>> +       if (ret)
>>> +               goto error;
>>>
>>> -       if (code)
>>> -               fwrite_unlocked(code, size, 1, fp);
>>> +       if (code) {
>>> +               ret = fwrite_unlocked(code, size, 1, fp);
>>> +               if (ret)
>>> +                       goto error;
>>> +       }
>>>
>>>          funlockfile(fp);
>>> -
>>> -       ret = 0;
>>> -
>>> -       return ret;
>>> +       return 0;
>>> +error:
>>> +       funlockfile(fp);
>>> +       return -1;
>>>   }
>>>
>>>   int
>>> --
>>> 2.17.1
>>>