[PATCH net-next] chelsio: Replace zero-length array with flexible-array member
From: Gustavo A. R. Silva
Date: Mon Feb 24 2020 - 11:27:41 EST
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
---
drivers/net/ethernet/chelsio/cxgb3/cxgb3_ioctl.h | 2 +-
drivers/net/ethernet/chelsio/cxgb3/t3_cpl.h | 2 +-
drivers/net/ethernet/chelsio/cxgb4/clip_tbl.h | 2 +-
drivers/net/ethernet/chelsio/cxgb4/cudbg_entity.h | 8 ++++----
drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c | 2 +-
drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.h | 2 +-
drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h | 2 +-
drivers/net/ethernet/chelsio/cxgb4/l2t.c | 2 +-
drivers/net/ethernet/chelsio/cxgb4/sched.h | 2 +-
drivers/net/ethernet/chelsio/cxgb4/smt.h | 2 +-
drivers/net/ethernet/chelsio/cxgb4/t4_msg.h | 2 +-
drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h | 2 +-
drivers/net/ethernet/chelsio/libcxgb/libcxgb_ppm.h | 4 ++--
13 files changed, 17 insertions(+), 17 deletions(-)
diff --git a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_ioctl.h b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_ioctl.h
index b19e4376ba76..401827b82aa1 100644
--- a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_ioctl.h
+++ b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_ioctl.h
@@ -79,7 +79,7 @@ struct ch_mem_range {
uint32_t addr;
uint32_t len;
uint32_t version;
- uint8_t buf[0];
+ uint8_t buf[];
};
struct ch_qset_params {
diff --git a/drivers/net/ethernet/chelsio/cxgb3/t3_cpl.h b/drivers/net/ethernet/chelsio/cxgb3/t3_cpl.h
index 852c399a8b0a..68bb5f39f3f1 100644
--- a/drivers/net/ethernet/chelsio/cxgb3/t3_cpl.h
+++ b/drivers/net/ethernet/chelsio/cxgb3/t3_cpl.h
@@ -1448,7 +1448,7 @@ struct cpl_rdma_terminate {
#endif
__be32 msn;
__be32 mo;
- __u8 data[0];
+ __u8 data[];
};
/* cpl_rdma_terminate.tid_len fields */
diff --git a/drivers/net/ethernet/chelsio/cxgb4/clip_tbl.h b/drivers/net/ethernet/chelsio/cxgb4/clip_tbl.h
index a0e0ae19649f..290c1058069a 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/clip_tbl.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/clip_tbl.h
@@ -29,7 +29,7 @@ struct clip_tbl {
atomic_t nfree;
struct list_head ce_free_head;
void *cl_list;
- struct list_head hash_list[0];
+ struct list_head hash_list[];
};
enum {
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cudbg_entity.h b/drivers/net/ethernet/chelsio/cxgb4/cudbg_entity.h
index f5be3ee1bdb4..dcab94cc2dee 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cudbg_entity.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/cudbg_entity.h
@@ -82,7 +82,7 @@ struct cudbg_ulprx_la {
struct cudbg_tp_la {
u32 size;
u32 mode;
- u8 data[0];
+ u8 data[];
};
static const char * const cudbg_region[] = {
@@ -134,7 +134,7 @@ struct cudbg_meminfo {
struct cudbg_cim_pif_la {
int size;
- u8 data[0];
+ u8 data[];
};
struct cudbg_clk_info {
@@ -339,13 +339,13 @@ struct cudbg_qdesc_entry {
u32 qid;
u32 desc_size;
u32 num_desc;
- u8 data[0]; /* Must be last */
+ u8 data[]; /* Must be last */
};
struct cudbg_qdesc_info {
u32 qdesc_entry_size;
u32 num_queues;
- u8 data[0]; /* Must be last */
+ u8 data[]; /* Must be last */
};
#define IREG_NUM_ELEM 4
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
index de30d61af065..fe883cb1a7af 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
@@ -984,7 +984,7 @@ static const char * const devlog_facility_strings[] = {
struct devlog_info {
unsigned int nentries; /* number of entries in log[] */
unsigned int first; /* first [temporal] entry in log[] */
- struct fw_devlog_e log[0]; /* Firmware Device Log */
+ struct fw_devlog_e log[]; /* Firmware Device Log */
};
/* Dump a Firmaware Device Log entry.
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.h b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.h
index ba95e13d52da..1471cf0deb58 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.h
@@ -49,7 +49,7 @@ struct seq_tab {
unsigned int rows; /* # of entries */
unsigned char width; /* size in bytes of each entry */
unsigned char skip_first; /* whether the first line is a header */
- char data[0]; /* the table data */
+ char data[]; /* the table data */
};
static inline unsigned int hex2val(char c)
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h
index a4b99edcc339..125868c6770a 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h
@@ -289,6 +289,6 @@ struct cxgb4_link {
struct cxgb4_tc_u32_table {
unsigned int size; /* number of entries in table */
- struct cxgb4_link table[0]; /* Jump table */
+ struct cxgb4_link table[]; /* Jump table */
};
#endif /* __CXGB4_TC_U32_PARSE_H */
diff --git a/drivers/net/ethernet/chelsio/cxgb4/l2t.c b/drivers/net/ethernet/chelsio/cxgb4/l2t.c
index 1a16449e9deb..12c3354172cd 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/l2t.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/l2t.c
@@ -59,7 +59,7 @@ struct l2t_data {
rwlock_t lock;
atomic_t nfree; /* number of free entries */
struct l2t_entry *rover; /* starting point for next allocation */
- struct l2t_entry l2tab[0]; /* MUST BE LAST */
+ struct l2t_entry l2tab[]; /* MUST BE LAST */
};
static inline unsigned int vlan_prio(const struct l2t_entry *e)
diff --git a/drivers/net/ethernet/chelsio/cxgb4/sched.h b/drivers/net/ethernet/chelsio/cxgb4/sched.h
index 5cc74a5a1774..5f8b871d79af 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/sched.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/sched.h
@@ -82,7 +82,7 @@ struct sched_class {
struct sched_table { /* per port scheduling table */
u8 sched_size;
- struct sched_class tab[0];
+ struct sched_class tab[];
};
static inline bool can_sched(struct net_device *dev)
diff --git a/drivers/net/ethernet/chelsio/cxgb4/smt.h b/drivers/net/ethernet/chelsio/cxgb4/smt.h
index 1268d6e93a47..541249d78914 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/smt.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/smt.h
@@ -66,7 +66,7 @@ struct smt_entry {
struct smt_data {
unsigned int smt_size;
rwlock_t lock;
- struct smt_entry smtab[0];
+ struct smt_entry smtab[];
};
struct smt_data *t4_init_smt(void);
diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4_msg.h b/drivers/net/ethernet/chelsio/cxgb4/t4_msg.h
index 575c6abcdae7..7d874f03d6c5 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/t4_msg.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/t4_msg.h
@@ -1511,7 +1511,7 @@ struct ulptx_sgl {
__be32 cmd_nsge;
__be32 len0;
__be64 addr0;
- struct ulptx_sge_pair sge[0];
+ struct ulptx_sge_pair sge[];
};
struct ulptx_idata {
diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h b/drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h
index accad1101ad1..703effc00a05 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h
@@ -737,7 +737,7 @@ struct fw_flowc_mnemval {
struct fw_flowc_wr {
__be32 op_to_nparams;
__be32 flowid_len16;
- struct fw_flowc_mnemval mnemval[0];
+ struct fw_flowc_mnemval mnemval[];
};
#define FW_FLOWC_WR_NPARAMS_S 0
diff --git a/drivers/net/ethernet/chelsio/libcxgb/libcxgb_ppm.h b/drivers/net/ethernet/chelsio/libcxgb/libcxgb_ppm.h
index 7b02c200dd1e..1b4156461ba1 100644
--- a/drivers/net/ethernet/chelsio/libcxgb/libcxgb_ppm.h
+++ b/drivers/net/ethernet/chelsio/libcxgb/libcxgb_ppm.h
@@ -122,7 +122,7 @@ struct cxgbi_ppm_pool {
unsigned int base; /* base index */
unsigned int next; /* next possible free index */
spinlock_t lock; /* ppm pool lock */
- unsigned long bmap[0];
+ unsigned long bmap[];
} ____cacheline_aligned_in_smp;
struct cxgbi_ppm {
@@ -145,7 +145,7 @@ struct cxgbi_ppm {
unsigned int next;
unsigned int max_index_in_edram;
unsigned long *ppod_bmap;
- struct cxgbi_ppod_data ppod_data[0];
+ struct cxgbi_ppod_data ppod_data[];
};
#define DDP_THRESHOLD 512
--
2.25.0