2014-06-28 21:52:41

by Toralf Förster

Subject: lib/argv_split.c : should argv be kfree'ed ?

/me wonders if this patch is needed here :


diff --git a/lib/argv_split.c b/lib/argv_split.c
index e927ed0..7de4cb4 100644
--- a/lib/argv_split.c
+++ b/lib/argv_split.c
@@ -85,6 +85,7 @@ char **argv_split(gfp_t gfp, const char *str, int *argcp)
*argv++ = argv_str;
}
}
+ kfree (argv);
*argv = NULL;

if (argcp)

--
Toralf

2014-06-28 22:04:33

by Mateusz Guzik

Subject: Re: lib/argv_split.c : should argv be kfree'ed ?

On Sat, Jun 28, 2014 at 11:52:37PM +0200, Toralf Förster wrote:
> /me wonders if this patch is needed here :
>
>
> diff --git a/lib/argv_split.c b/lib/argv_split.c
> index e927ed0..7de4cb4 100644
> --- a/lib/argv_split.c
> +++ b/lib/argv_split.c
> @@ -85,6 +85,7 @@ char **argv_split(gfp_t gfp, const char *str, int *argcp)
> *argv++ = argv_str;
> }
> }
> + kfree (argv);
> *argv = NULL;
>
> if (argcp)
>

No, see argv_free.

--
Mateusz Guzik

2014-06-29 14:40:21

by Toralf Förster

Subject: Re: lib/argv_split.c : should argv be kfree'ed ?

On 06/29/2014 12:04 AM, Mateusz Guzik wrote:
> On Sat, Jun 28, 2014 at 11:52:37PM +0200, Toralf Förster wrote:
>> /me wonders if this patch is needed here :
>>
>>
>> diff --git a/lib/argv_split.c b/lib/argv_split.c
>> index e927ed0..7de4cb4 100644
>> --- a/lib/argv_split.c
>> +++ b/lib/argv_split.c
>> @@ -85,6 +85,7 @@ char **argv_split(gfp_t gfp, const char *str, int *argcp)
>> *argv++ = argv_str;
>> }
>> }
>> + kfree (argv);
>> *argv = NULL;
>>
>> if (argcp)
>>
>
> No, see argv_free.
>
Ah, understood, it is in the responsibility of the caller to avoid the memleak.
BTW may I ask you about your opinion about this warning of cppcheck in lib/flex_array.c:

for (part_nr = start_part; part_nr <= end_part; part_nr++) {<--- Memory leak: part
part = __fa_get_part(fa, part_nr, flags);
if (!part)
return -ENOMEM;
}
return 0;

--
Toralf

2014-06-29 15:37:23

by Mateusz Guzik

Subject: Re: lib/argv_split.c : should argv be kfree'ed ?

On Sun, Jun 29, 2014 at 04:40:17PM +0200, Toralf Förster wrote:
> On 06/29/2014 12:04 AM, Mateusz Guzik wrote:
> > On Sat, Jun 28, 2014 at 11:52:37PM +0200, Toralf Förster wrote:
> >> /me wonders if this patch is needed here :
> >>
> >>
> >> diff --git a/lib/argv_split.c b/lib/argv_split.c
> >> index e927ed0..7de4cb4 100644
> >> --- a/lib/argv_split.c
> >> +++ b/lib/argv_split.c
> >> @@ -85,6 +85,7 @@ char **argv_split(gfp_t gfp, const char *str, int *argcp)
> >> *argv++ = argv_str;
> >> }
> >> }
> >> + kfree (argv);
> >> *argv = NULL;
> >>
> >> if (argcp)
> >>
> >
> > No, see argv_free.
> >
> Ah, understood, it is in the responsibility of the caller to avoid the memleak.
> BTW may I ask you about your opinion about this warning of cppcheck in lib/flex_array.c:
>
> for (part_nr = start_part; part_nr <= end_part; part_nr++) {<--- Memory leak: part
> part = __fa_get_part(fa, part_nr, flags);
> if (!part)
> return -ENOMEM;
> }
> return 0;
>


static struct flex_array_part *
__fa_get_part(struct flex_array *fa, int part_nr, gfp_t flags)
{
struct flex_array_part *part = fa->parts[part_nr];
if (!part) {
part = kmalloc(sizeof(struct flex_array_part), flags);
if (!part)
return NULL;
if (!(flags & __GFP_ZERO))
memset(part, FLEX_ARRAY_FREE,
sizeof(struct flex_array_part));
fa->parts[part_nr] = part;

^^^^^^^^^^^^^^^^^^^^^^^^^^
}
return part;
}


Allocated memory is not leaked. It is stored in 'fa' and is perfectly
reachable afterwards.

'part' in flex_array_prealloc is only used for error checking.

--
Mateusz Guzik