2020-07-24 10:08:54

by Wangshaobo (bobo)

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

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 <[email protected]>
---
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

2020-07-28 12:16:21

by Arnaldo Carvalho de Melo

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

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 <[email protected]>
> ---
> 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

2020-07-29 23:50:28

by Ian Rogers

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

On Fri, Jul 24, 2020 at 3:07 AM Wang ShaoBo <[email protected]> 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 <[email protected]>
> ---
> 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
>

2020-07-30 01:13:44

by Arnaldo Carvalho de Melo

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

On July 29, 2020 8:47:36 PM GMT-03:00, Ian Rogers <[email protected]> wrote:
>On Fri, Jul 24, 2020 at 3:07 AM Wang ShaoBo
><[email protected]> 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 <[email protected]>
>> ---
>> 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.

2020-07-30 10:07:30

by Arnaldo Carvalho de Melo

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

Em Wed, Jul 29, 2020 at 04:47:36PM -0700, Ian Rogers escreveu:
> On Fri, Jul 24, 2020 at 3:07 AM Wang ShaoBo <[email protected]> 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 <[email protected]>
> > ---
> > 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

2020-07-31 12:00:00

by Wangshaobo (bobo)

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

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 <[email protected]> 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 <[email protected]>
>>> ---
>>> 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
>>>