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>

5 files changed, 7 insertions, 7 deletions

diff --git a/drivers/net/ethernet/freescale/enetc/enetc_hw.h b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
index 1514e6a4a3ff..ce5b677e8c2f 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_hw.h
+++ b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
@@ -881,7 +881,7 @@ struct sgcl_data {
 	u32		bth;
 	u32		ct;
 	u32		cte;
-	struct sgce	sgcl[0];
+	struct sgce	sgcl[];
 };
 
 #define ENETC_CBDR_FMI_MR	BIT(0)
diff --git a/drivers/net/ethernet/i825xx/sun3_82586.h b/drivers/net/ethernet/i825xx/sun3_82586.h
index 79aef681ac85..451cb3d26cb5 100644
--- a/drivers/net/ethernet/i825xx/sun3_82586.h
+++ b/drivers/net/ethernet/i825xx/sun3_82586.h
@@ -250,7 +250,7 @@ struct mcsetup_cmd_struct
   unsigned short cmd_cmd;
   unsigned short cmd_link;
   unsigned short mc_cnt;		/* number of bytes in the MC-List */
-  unsigned char  mc_list[0][6];  	/* pointer to 6 bytes entries */
+  unsigned char  mc_list[][6];  	/* pointer to 6 bytes entries */
 };
 
 /*
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 {
diff --git a/drivers/net/ethernet/qlogic/qed/qed_mfw_hsi.h b/drivers/net/ethernet/qlogic/qed/qed_mfw_hsi.h
index b70ee8200e15..6459dd3feb37 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_mfw_hsi.h
+++ b/drivers/net/ethernet/qlogic/qed/qed_mfw_hsi.h
@@ -2470,6 +2470,6 @@ struct nvm_meta_bin_t {
 	u32 version;
 #define NVM_META_BIN_VERSION 1
 	u32 num_options;
-	u32 options[0];
+	u32 options[];
 };
 #endif
diff --git a/drivers/net/ethernet/ti/davinci_mdio.c b/drivers/net/ethernet/ti/davinci_mdio.c
index a4efd5e35158..fce2626e34fa 100644
--- a/drivers/net/ethernet/ti/davinci_mdio.c
+++ b/drivers/net/ethernet/ti/davinci_mdio.c
@@ -70,7 +70,7 @@ struct davinci_mdio_regs {
 #define USERACCESS_DATA		(0xffff)
 
 		u32	physel;
-	}	user[0];
+	}	user[];
 };
 
 static const struct mdio_platform_data default_pdata = {