diff options
| author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-02-24 10:32:52 -0600 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-02-24 15:26:17 -0800 |
| commit | f49b2759821e3af7c3740b52ca91053b16c91103 (patch) | |
| tree | b05ada22b0dc60a17935a1e0a6ccaa25385479b9 | |
| parent | 65dc2f1a44df01eab3c93b7ecdd3fb393f9e81a2 (diff) | |
toshiba: Replace zero-length array with flexible-array member
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@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/ethernet/toshiba/ps3_gelic_net.h | 2 | ||||
| -rw-r--r-- | drivers/net/ethernet/toshiba/ps3_gelic_wireless.h | 2 | ||||
| -rw-r--r-- | drivers/net/ethernet/toshiba/spider_net.h | 2 | ||||
| -rw-r--r-- | drivers/net/ethernet/toshiba/tc35815.c | 2 |
4 files changed, 4 insertions, 4 deletions
diff --git a/drivers/net/ethernet/toshiba/ps3_gelic_net.h b/drivers/net/ethernet/toshiba/ps3_gelic_net.h index 805903d..68f324e 100644 --- a/drivers/net/ethernet/toshiba/ps3_gelic_net.h +++ b/drivers/net/ethernet/toshiba/ps3_gelic_net.h @@ -308,7 +308,7 @@ struct gelic_port { struct gelic_card *card; struct net_device *netdev; enum gelic_port_type type; - long priv[0]; /* long for alignment */ + long priv[]; /* long for alignment */ }; static inline struct gelic_card *port_to_card(struct gelic_port *p) diff --git a/drivers/net/ethernet/toshiba/ps3_gelic_wireless.h b/drivers/net/ethernet/toshiba/ps3_gelic_wireless.h index 4041d94..1f203d1 100644 --- a/drivers/net/ethernet/toshiba/ps3_gelic_wireless.h +++ b/drivers/net/ethernet/toshiba/ps3_gelic_wireless.h @@ -158,7 +158,7 @@ struct gelic_eurus_scan_info { __be32 reserved2; __be32 reserved3; __be32 reserved4; - u8 elements[0]; /* ie */ + u8 elements[]; /* ie */ } __packed; /* the hypervisor returns bbs up to 16 */ diff --git a/drivers/net/ethernet/toshiba/spider_net.h b/drivers/net/ethernet/toshiba/spider_net.h index c0c68cb..05b1a07 100644 --- a/drivers/net/ethernet/toshiba/spider_net.h +++ b/drivers/net/ethernet/toshiba/spider_net.h @@ -470,7 +470,7 @@ struct spider_net_card { struct spider_net_extra_stats spider_stats; /* Must be last item in struct */ - struct spider_net_descr darray[0]; + struct spider_net_descr darray[]; }; #endif diff --git a/drivers/net/ethernet/toshiba/tc35815.c b/drivers/net/ethernet/toshiba/tc35815.c index 3fd43d3..b50c3ec 100644 --- a/drivers/net/ethernet/toshiba/tc35815.c +++ b/drivers/net/ethernet/toshiba/tc35815.c @@ -367,7 +367,7 @@ struct TxFD { struct RxFD { struct FDesc fd; - struct BDesc bd[0]; /* variable length */ + struct BDesc bd[]; /* variable length */ }; struct FrFD { |