Use __member_size() to get the size of the flex-array member at compile
time, instead of the convoluted expression `__struct_size(p) - sizeof(*p)`

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
 drivers/gpu/drm/nouveau/nvif/outp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/nouveau/nvif/outp.c b/drivers/gpu/drm/nouveau/nvif/outp.c
index 1ea20b2bdd29..32f6c5eb92af 100644
--- a/drivers/gpu/drm/nouveau/nvif/outp.c
+++ b/drivers/gpu/drm/nouveau/nvif/outp.c
@@ -198,7 +198,7 @@ nvif_outp_hda_eld(struct nvif_outp *outp, int head, void *data, u32 size)
 	DEFINE_RAW_FLEX(struct nvif_outp_hda_eld_v0, mthd, data, 128);
 	int ret;
 
-	if (WARN_ON(size > (__struct_size(mthd) - sizeof(*mthd))))
+	if (WARN_ON(size > __member_size(mthd->data)))
 		return -EINVAL;
 
 	mthd->version = 0;
-- 
2.43.0

On Tue, Apr 22, 2025 at 09:45:39AM -0600, Gustavo A. R. Silva wrote:
> Use __member_size() to get the size of the flex-array member at compile
> time, instead of the convoluted expression `__struct_size(p) - sizeof(*p)`
> 
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Applied to drm-misc-next, thanks!

On Tue, Apr 22, 2025 at 09:45:39AM -0600, Gustavo A. R. Silva wrote:
> Use __member_size() to get the size of the flex-array member at compile
> time, instead of the convoluted expression `__struct_size(p) - sizeof(*p)`
> 
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Reviewed-by: Kees Cook <kees@kernel.org>

-- 
Kees Cook