Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions).
As found with Coccinelle[1], add __counted_by for struct mca_data. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: "Martin PoviĊĦer" <povik+...@cutebit.org> Cc: Liam Girdwood <lgirdw...@gmail.com> Cc: Mark Brown <broo...@kernel.org> Cc: Jaroslav Kysela <pe...@perex.cz> Cc: Takashi Iwai <ti...@suse.com> Cc: as...@lists.linux.dev Cc: alsa-de...@alsa-project.org Signed-off-by: Kees Cook <keesc...@chromium.org> --- sound/soc/apple/mca.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/soc/apple/mca.c b/sound/soc/apple/mca.c index ce77934f3eef..99e547ef95e6 100644 --- a/sound/soc/apple/mca.c +++ b/sound/soc/apple/mca.c @@ -161,7 +161,7 @@ struct mca_data { struct mutex port_mutex; int nclusters; - struct mca_cluster clusters[]; + struct mca_cluster clusters[] __counted_by(nclusters); }; static void mca_modify(struct mca_cluster *cl, int regoffset, u32 mask, u32 val) -- 2.34.1
