diff options
| author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-02-25 03:27:46 +0300 |
|---|---|---|
| committer | Kalle Valo <kvalo@codeaurora.org> | 2020-03-23 19:51:56 +0300 |
| commit | a1b7714b72fd2ba5dead01b465a9e37863051eff (patch) | |
| tree | e78f28e0e23b04a1f595b1811f9255bc0beacff5 /drivers/net/wireless/realtek/rtlwifi | |
| parent | 4bbf92b7a190b8d20c2ee0ef17a0dbc1e4ba4acb (diff) | |
| download | linux-a1b7714b72fd2ba5dead01b465a9e37863051eff.tar.xz | |
wireless: realtek: 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: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200225002746.GA26789@embeddedor
Diffstat (limited to 'drivers/net/wireless/realtek/rtlwifi')
| -rw-r--r-- | drivers/net/wireless/realtek/rtlwifi/wifi.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/net/wireless/realtek/rtlwifi/wifi.h b/drivers/net/wireless/realtek/rtlwifi/wifi.h index 1cff9f07c9e9..13421cf2d201 100644 --- a/drivers/net/wireless/realtek/rtlwifi/wifi.h +++ b/drivers/net/wireless/realtek/rtlwifi/wifi.h @@ -1051,13 +1051,13 @@ struct rtl_hdr_3addr { u8 addr2[ETH_ALEN]; u8 addr3[ETH_ALEN]; __le16 seq_ctl; - u8 payload[0]; + u8 payload[]; } __packed; struct rtl_info_element { u8 id; u8 len; - u8 data[0]; + u8 data[]; } __packed; struct rtl_probe_rsp { @@ -1068,7 +1068,7 @@ struct rtl_probe_rsp { /*SSID, supported rates, FH params, DS params, * CF params, IBSS params, TIM (if beacon), RSN */ - struct rtl_info_element info_element[0]; + struct rtl_info_element info_element[]; } __packed; /*LED related.*/ |