Messages in this thread | | | Date | Fri, 7 Jun 2019 20:07:17 +0800 | From | Gen Zhang <> | Subject | Re: [PATCH] clk: fix a missing-free bug in clk_cpy_name() |
| |
On Fri, Jun 07, 2019 at 11:10:37AM +0200, Jiri Slaby wrote: > On 07. 06. 19, 3:52, Gen Zhang wrote: > >>>>> @@ -3491,6 +3492,8 @@ static int clk_core_populate_parent_map(struct clk_core *core) > >>>>> kfree_const(parents[i].name); > >>>>> kfree_const(parents[i].fw_name); > >>>>> } while (--i >= 0); > >>>>> + kfree_const(parent->name); > >>>>> + kfree_const(parent->fw_name); > >>>> > >>>> Both of them were just freed in the loop above, no? > >>> for (i = 0, parent = parents; i < num_parents; i++, parent++) > >>> Is 'parent' the same as the one from the loop above? > >> > >> Yes. Did it change somehow? > > parent++? > > parent++ is done after the loop body. Or what do you mean? > > >>> Moreover, should 'parents[i].name' and 'parents[i].fw_name' be freed by > >>> kfree_const()? > >>> > >> > >> Yes? They're allocated with kstrdup_const() in clk_cpy_name(), or > >> they're NULL by virtue of the kcalloc and then kfree_const() does > >> nothing. > > I re-examined clk_cpy_name(). They are the second parameter of > > clk_cpy_name(). The first parameter is allocated, not the second one. > > So 'parent->name' and 'parent->fw_name' should be freed, not > > 'parents[i].name' or 'parents[i].fw_name'. Am I totally misunderstanding > > this clk_cpy_name()? :-( > > The second parameter (the source) is parent_data[i].*, not parents[i].* > (the destination). parent->fw_name and parent->name are properly freed > in the do {} while loop as parents[i].name and parents[i].fw_name, given > i hasn't changed yet. I am not sure what you mean at all. Are you > uncertain about the C code flow? > > thanks, > -- > js > suse labs Thanks your patient explainaton. I think I need some time to figure out this part of code.
Thanks Gen
| |