treewide: Replace zero-length arrays with flexible-array members

There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].

This code was transformed with the help of Coccinelle:
(next-20220214$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)

@@
identifier S, member, array;
type T1, T2;
@@

struct S {
  ...
  T1 member;
  T2 array[
- 0
  ];
};

UAPI and wireless changes were intentionally excluded from this patch
and will be sent out separately.

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/78
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/npc.h b/drivers/net/ethernet/marvell/octeontx2/af/npc.h
index 77fd39e2c8db..9b6e587e78b4 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/npc.h
+++ b/drivers/net/ethernet/marvell/octeontx2/af/npc.h
@@ -455,7 +455,7 @@ struct npc_coalesced_kpu_prfl {
 	u8 name[NPC_NAME_LEN]; /* KPU Profile name */
 	u64 version; /* KPU firmware/profile version */
 	u8 num_prfl; /* No of NPC profiles. */
-	u16 prfl_sz[0];
+	u16 prfl_sz[];
 };
 
 struct npc_mcam_kex {
@@ -482,7 +482,7 @@ struct npc_kpu_fwdata {
 	 * struct npc_kpu_profile_cam[entries];
 	 * struct npc_kpu_profile_action[entries];
 	 */
-	u8	data[0];
+	u8	data[];
 } __packed;
 
 struct npc_lt_def {
@@ -572,7 +572,7 @@ struct npc_kpu_profile_fwdata {
 	 *  Custom KPU CAM and ACTION configuration entries.
 	 * struct npc_kpu_fwdata kpu[kpus];
 	 */
-	u8	data[0];
+	u8	data[];
 } __packed;
 
 struct rvu_npc_mcam_rule {