2012-10-17 08:29:05

by Hyunchul Lee

[permalink] [raw]
Subject: [PATCH] perf probe: convert_name_to_addr() allocated the wrong size buffers for names

The function allocated wrong size buffers for names

Cc: Masami Hiramatsu <[email protected]>
Cc: Srikar Dronamraju <[email protected]>
Signed-off-by: Hyeoncheol Lee <[email protected]>
---
tools/perf/util/probe-event.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 49a256e..5cd7c42 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2273,6 +2273,8 @@ int show_available_funcs(const char *target, struct strfilter *_filter,
return available_user_funcs(target);
}

+#define MAX_ADDRNAME_LEN (3 + sizeof(unsigned long long) * 2)
+
/*
* uprobe_events only accepts address:
* Convert function and any offset to address
@@ -2332,7 +2334,7 @@ static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec)
if (!pev->group) {
char *ptr1, *ptr2, *exec_copy;

- pev->group = zalloc(sizeof(char *) * 64);
+ pev->group = zalloc(sizeof(char) * 64);
exec_copy = strdup(exec);
if (!exec_copy) {
ret = -ENOMEM;
@@ -2352,14 +2354,15 @@ static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec)
free(exec_copy);
}
free(pp->function);
- pp->function = zalloc(sizeof(char *) * MAX_PROBE_ARGS);
+ pp->function = zalloc(sizeof(char) * MAX_ADDRNAME_LEN);
if (!pp->function) {
ret = -ENOMEM;
pr_warning("Failed to allocate memory by zalloc.\n");
goto out;
}
- e_snprintf(pp->function, MAX_PROBE_ARGS, "0x%llx", vaddr);
- ret = 0;
+ ret = e_snprintf(pp->function, MAX_ADDRNAME_LEN, "0x%llx", vaddr);
+ if (ret > 0)
+ ret = 0;

out:
if (map) {
--
1.7.10.4


Subject: Re: [PATCH] perf probe: convert_name_to_addr() allocated the wrong size buffers for names

(2012/10/17 17:28), Hyeoncheol Lee wrote:
> The function allocated wrong size buffers for names
>
> Cc: Masami Hiramatsu <[email protected]>
> Cc: Srikar Dronamraju <[email protected]>
> Signed-off-by: Hyeoncheol Lee <[email protected]>
> ---
> tools/perf/util/probe-event.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index 49a256e..5cd7c42 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -2273,6 +2273,8 @@ int show_available_funcs(const char *target, struct strfilter *_filter,
> return available_user_funcs(target);
> }
>

Please add a comment like below on the code.

/*
* sizeof(type) * 2 returns the maximum length of hexadecimal number
* of type, because each half byte is encoding in one hex character.
* Another 3 bytes are for "0x" and null character.
*/

Others are OK for me :)

Thanks!

> +#define MAX_ADDRNAME_LEN (3 + sizeof(unsigned long long) * 2)
> +
> /*
> * uprobe_events only accepts address:
> * Convert function and any offset to address
> @@ -2332,7 +2334,7 @@ static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec)
> if (!pev->group) {
> char *ptr1, *ptr2, *exec_copy;
>
> - pev->group = zalloc(sizeof(char *) * 64);
> + pev->group = zalloc(sizeof(char) * 64);
> exec_copy = strdup(exec);
> if (!exec_copy) {
> ret = -ENOMEM;
> @@ -2352,14 +2354,15 @@ static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec)
> free(exec_copy);
> }
> free(pp->function);
> - pp->function = zalloc(sizeof(char *) * MAX_PROBE_ARGS);
> + pp->function = zalloc(sizeof(char) * MAX_ADDRNAME_LEN);
> if (!pp->function) {
> ret = -ENOMEM;
> pr_warning("Failed to allocate memory by zalloc.\n");
> goto out;
> }
> - e_snprintf(pp->function, MAX_PROBE_ARGS, "0x%llx", vaddr);
> - ret = 0;
> + ret = e_snprintf(pp->function, MAX_ADDRNAME_LEN, "0x%llx", vaddr);
> + if (ret > 0)
> + ret = 0;
>
> out:
> if (map) {
>


--
Masami HIRAMATSU
IT Management Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: [email protected]

2012-10-18 01:20:40

by Namhyung Kim

[permalink] [raw]
Subject: Re: [PATCH] perf probe: convert_name_to_addr() allocated the wrong size buffers for names

Hi,

On Wed, 17 Oct 2012 20:06:54 +0900, Masami Hiramatsu wrote:
> (2012/10/17 17:28), Hyeoncheol Lee wrote:
>> The function allocated wrong size buffers for names
>>
>> Cc: Masami Hiramatsu <[email protected]>
>> Cc: Srikar Dronamraju <[email protected]>
>> Signed-off-by: Hyeoncheol Lee <[email protected]>
>> ---
>> tools/perf/util/probe-event.c | 11 +++++++----
>> 1 file changed, 7 insertions(+), 4 deletions(-)
>>
>> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
>> index 49a256e..5cd7c42 100644
>> --- a/tools/perf/util/probe-event.c
>> +++ b/tools/perf/util/probe-event.c
>> @@ -2273,6 +2273,8 @@ int show_available_funcs(const char *target, struct strfilter *_filter,
>> return available_user_funcs(target);
>> }
>>
>
> Please add a comment like below on the code.
>
> /*
> * sizeof(type) * 2 returns the maximum length of hexadecimal number
> * of type, because each half byte is encoding in one hex character.
> * Another 3 bytes are for "0x" and null character.
> */
>
> Others are OK for me :)
>
> Thanks!
>
>> +#define MAX_ADDRNAME_LEN (3 + sizeof(unsigned long long) * 2)
>> +
>> /*
>> * uprobe_events only accepts address:
>> * Convert function and any offset to address
>> @@ -2332,7 +2334,7 @@ static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec)
>> if (!pev->group) {
>> char *ptr1, *ptr2, *exec_copy;
>>
>> - pev->group = zalloc(sizeof(char *) * 64);
>> + pev->group = zalloc(sizeof(char) * 64);

I guess we don't need this 'sizeof(char)' part?


>> exec_copy = strdup(exec);
>> if (!exec_copy) {
>> ret = -ENOMEM;
>> @@ -2352,14 +2354,15 @@ static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec)
>> free(exec_copy);
>> }
>> free(pp->function);
>> - pp->function = zalloc(sizeof(char *) * MAX_PROBE_ARGS);
>> + pp->function = zalloc(sizeof(char) * MAX_ADDRNAME_LEN);

Ditto.

Thanks,
Namhyung


>> if (!pp->function) {
>> ret = -ENOMEM;
>> pr_warning("Failed to allocate memory by zalloc.\n");
>> goto out;
>> }
>> - e_snprintf(pp->function, MAX_PROBE_ARGS, "0x%llx", vaddr);
>> - ret = 0;
>> + ret = e_snprintf(pp->function, MAX_ADDRNAME_LEN, "0x%llx", vaddr);
>> + if (ret > 0)
>> + ret = 0;
>>
>> out:
>> if (map) {
>>

Subject: Re: [PATCH] perf probe: convert_name_to_addr() allocated the wrong size buffers for names

(2012/10/18 10:20), Namhyung Kim wrote:
> Hi,
>
> On Wed, 17 Oct 2012 20:06:54 +0900, Masami Hiramatsu wrote:
>> (2012/10/17 17:28), Hyeoncheol Lee wrote:
>>> The function allocated wrong size buffers for names
>>>
>>> Cc: Masami Hiramatsu <[email protected]>
>>> Cc: Srikar Dronamraju <[email protected]>
>>> Signed-off-by: Hyeoncheol Lee <[email protected]>
>>> ---
>>> tools/perf/util/probe-event.c | 11 +++++++----
>>> 1 file changed, 7 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
>>> index 49a256e..5cd7c42 100644
>>> --- a/tools/perf/util/probe-event.c
>>> +++ b/tools/perf/util/probe-event.c
>>> @@ -2273,6 +2273,8 @@ int show_available_funcs(const char *target, struct strfilter *_filter,
>>> return available_user_funcs(target);
>>> }
>>>
>>
>> Please add a comment like below on the code.
>>
>> /*
>> * sizeof(type) * 2 returns the maximum length of hexadecimal number
>> * of type, because each half byte is encoding in one hex character.
>> * Another 3 bytes are for "0x" and null character.
>> */
>>
>> Others are OK for me :)
>>
>> Thanks!
>>
>>> +#define MAX_ADDRNAME_LEN (3 + sizeof(unsigned long long) * 2)
>>> +
>>> /*
>>> * uprobe_events only accepts address:
>>> * Convert function and any offset to address
>>> @@ -2332,7 +2334,7 @@ static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec)
>>> if (!pev->group) {
>>> char *ptr1, *ptr2, *exec_copy;
>>>
>>> - pev->group = zalloc(sizeof(char *) * 64);
>>> + pev->group = zalloc(sizeof(char) * 64);
>
> I guess we don't need this 'sizeof(char)' part?

Indeed, we don't need it from the viewpoint of C.
However I'd like to keep that, because it gives us a hint that
this buffer is used for string.

Thank you,

>
>
>>> exec_copy = strdup(exec);
>>> if (!exec_copy) {
>>> ret = -ENOMEM;
>>> @@ -2352,14 +2354,15 @@ static int convert_name_to_addr(struct perf_probe_event *pev, const char *exec)
>>> free(exec_copy);
>>> }
>>> free(pp->function);
>>> - pp->function = zalloc(sizeof(char *) * MAX_PROBE_ARGS);
>>> + pp->function = zalloc(sizeof(char) * MAX_ADDRNAME_LEN);
>
> Ditto.
>
> Thanks,
> Namhyung
>
>
>>> if (!pp->function) {
>>> ret = -ENOMEM;
>>> pr_warning("Failed to allocate memory by zalloc.\n");
>>> goto out;
>>> }
>>> - e_snprintf(pp->function, MAX_PROBE_ARGS, "0x%llx", vaddr);
>>> - ret = 0;
>>> + ret = e_snprintf(pp->function, MAX_ADDRNAME_LEN, "0x%llx", vaddr);
>>> + if (ret > 0)
>>> + ret = 0;
>>>
>>> out:
>>> if (map) {
>>>


--
Masami HIRAMATSU
IT Management Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: [email protected]