diff options
| author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-02-25 05:04:13 +0300 |
|---|---|---|
| committer | Kalle Valo <kvalo@codeaurora.org> | 2020-03-23 20:11:09 +0300 |
| commit | 2a6be797d232a4aec7be013964a5c2b8a1a46a3e (patch) | |
| tree | e5922f955bcd68a8644cf6a26be57f1e1cfd6113 /drivers/net/wireless/marvell/mwl8k.c | |
| parent | 7b9307134058cefb9c2416266a7ae6fc4af57915 (diff) | |
| download | linux-2a6be797d232a4aec7be013964a5c2b8a1a46a3e.tar.xz | |
wireless: marvell: 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>
Acked-by: Ganapathi Bhat <ganapathi.bhat@nxp.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200225020413.GA8057@embeddedor
Diffstat (limited to 'drivers/net/wireless/marvell/mwl8k.c')
| -rw-r--r-- | drivers/net/wireless/marvell/mwl8k.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/net/wireless/marvell/mwl8k.c b/drivers/net/wireless/marvell/mwl8k.c index d55f229abeea..47fb4b3ea004 100644 --- a/drivers/net/wireless/marvell/mwl8k.c +++ b/drivers/net/wireless/marvell/mwl8k.c @@ -592,7 +592,7 @@ struct mwl8k_cmd_pkt { __u8 seq_num; __u8 macid; __le16 result; - char payload[0]; + char payload[]; } __packed; /* @@ -806,7 +806,7 @@ static int mwl8k_load_firmware(struct ieee80211_hw *hw) struct mwl8k_dma_data { __le16 fwlen; struct ieee80211_hdr wh; - char data[0]; + char data[]; } __packed; /* Routines to add/remove DMA header from skb. */ @@ -2955,7 +2955,7 @@ mwl8k_cmd_rf_antenna(struct ieee80211_hw *hw, int antenna, int mask) struct mwl8k_cmd_set_beacon { struct mwl8k_cmd_pkt header; __le16 beacon_len; - __u8 beacon[0]; + __u8 beacon[]; }; static int mwl8k_cmd_set_beacon(struct ieee80211_hw *hw, |