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

From: Mateusz Guzik
Date: Sun Jun 29 2014 - 11:37:34 EST


On Sun, Jun 29, 2014 at 04:40:17PM +0200, Toralf FÃrster wrote:
> On 06/29/2014 12:04 AM, Mateusz Guzik wrote:
> > On Sat, Jun 28, 2014 at 11:52:37PM +0200, Toralf FÃrster 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
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