On 4/28/25 08:36, Geert Uytterhoeven wrote:
Hi Kees,
On Sat, 26 Apr 2025 at 13:33, Helge Deller <del...@gmx.de> wrote:
On 4/26/25 08:23, Kees Cook wrote:
In preparation for making the kmalloc family of allocators type aware,
we need to make sure that the returned type from the allocation matches
the type of the variable being assigned. (Before, the allocator would
always return "void *", which can be implicitly cast to any pointer type.)
The assigned type is "struct dac_info *" but the returned type will be
"struct ics5342_info *", which has a larger allocation size. This is
by design, as struct ics5342_info contains struct dac_info as its first
member. Cast the allocation type to match the assignment.
Signed-off-by: Kees Cook <k...@kernel.org>
Thanks for your patch, which is now commit 8d2f0f5bbac87b9d ("fbdev:
arkfb: Cast ics5342_init() allocation type") in fbdev/for-next.
I applied your patch, but wouldn't this untested patch be cleaner and fulfill
the
same purpose to match a kzalloc return type?
diff --git a/drivers/video/fbdev/arkfb.c b/drivers/video/fbdev/arkfb.c
index 7d131e3d159a..a57c8a992e11 100644
--- a/drivers/video/fbdev/arkfb.c
+++ b/drivers/video/fbdev/arkfb.c
@@ -431,7 +431,8 @@ static struct dac_ops ics5342_ops = {
static struct dac_info * ics5342_init(dac_read_regs_t drr, dac_write_regs_t
dwr, void *data)
{
- struct dac_info *info = (struct dac_info *)kzalloc(sizeof(struct
ics5342_info), GFP_KERNEL);
+ struct ics5342_info *ics_info = kzalloc(sizeof(struct ics5342_info),
GFP_KERNEL);
sizeof(*ics_info)?
+ struct dac_info *info = &ics_info->dac;
Exactly my thought when I noticed this commit. Adding casts makes
it harder to notice any future discrepancies.
I've changed it accordingly.
Helge
