staging: rtl8723bs: Replace one-element array with flexible-array in struct ndis_80211_var_ie
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].
Refactor the code according to the use of a flexible-array member in
struct ndis_80211_var_ie, instead of a one-element array.
Also, this helps with the ongoing efforts to enable -Warray-bounds and
fix the following warnings:
CC [M] drivers/staging/rtl8723bs/core/rtw_wlan_util.o
In file included from ./drivers/staging/rtl8723bs/include/drv_types.h:20,
from drivers/staging/rtl8723bs/core/rtw_wlan_util.c:9:
drivers/staging/rtl8723bs/core/rtw_wlan_util.c: In function ‘HT_caps_handler’:
./drivers/staging/rtl8723bs/include/basic_types.h:108:11: warning: array subscript 1 is above array bounds of ‘u8[1]’ {aka ‘unsigned char[1]’} [-Warray-bounds]
108 | (EF1BYTE(*((u8 *)(__pstart))))
| ^
./drivers/staging/rtl8723bs/include/basic_types.h:42:8: note: in definition of macro ‘EF1BYTE’
42 | ((u8)(_val))
| ^~~~
./drivers/staging/rtl8723bs/include/basic_types.h:127:4: note: in expansion of macro ‘LE_P1BYTE_TO_HOST_1BYTE’
127 | (LE_P1BYTE_TO_HOST_1BYTE(__pstart) >> (__bitoffset)) & \
| ^~~~~~~~~~~~~~~~~~~~~~~
./drivers/staging/rtl8723bs/include/rtw_ht.h:97:55: note: in expansion of macro ‘LE_BITS_TO_1BYTE’
97 | #define GET_HT_CAPABILITY_ELE_RX_STBC(_pEleStart) LE_BITS_TO_1BYTE((_pEleStart)+1, 0, 2)
| ^~~~~~~~~~~~~~~~
drivers/staging/rtl8723bs/core/rtw_wlan_util.c:1104:58: note: in expansion of macro ‘GET_HT_CAPABILITY_ELE_RX_STBC’
1104 | if (TEST_FLAG(phtpriv->stbc_cap, STBC_HT_ENABLE_TX) && GET_HT_CAPABILITY_ELE_RX_STBC(pIE->data)) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/rtl8723bs/core/rtw_wlan_util.c:1051:75: warning: array subscript 2 is above array bounds of ‘u8[1]’ {aka ‘unsigned char[1]’} [-Warray-bounds]
1051 | if ((pmlmeinfo->HT_caps.u.HT_cap_element.AMPDU_para & 0x3) > (pIE->data[i] & 0x3))
| ~~~~~~~~~^~~
drivers/staging/rtl8723bs/core/rtw_wlan_util.c: In function ‘check_assoc_AP’:
drivers/staging/rtl8723bs/core/rtw_wlan_util.c:1606:19: warning: array subscript 4 is above array bounds of ‘u8[1]’ {aka ‘unsigned char[1]’} [-Warray-bounds]
1606 | if (pIE->data[4] == 1)
| ~~~~~~~~~^~~
drivers/staging/rtl8723bs/core/rtw_wlan_util.c:1609:20: warning: array subscript 5 is above array bounds of ‘u8[1]’ {aka ‘unsigned char[1]’} [-Warray-bounds]
1609 | if (pIE->data[5] & RT_HT_CAP_USE_92SE)
| ~~~~~~~~~^~~
drivers/staging/rtl8723bs/core/rtw_wlan_util.c:1613:19: warning: array subscript 5 is above array bounds of ‘u8[1]’ {aka ‘unsigned char[1]’} [-Warray-bounds]
1613 | if (pIE->data[5] & RT_HT_CAP_USE_SOFTAP)
| ~~~~~~~~~^~~
drivers/staging/rtl8723bs/core/rtw_wlan_util.c:1617:20: warning: array subscript 6 is above array bounds of ‘u8[1]’ {aka ‘unsigned char[1]’} [-Warray-bounds]
1617 | if (pIE->data[6] & RT_HT_CAP_USE_JAGUAR_BCUT) {
| ~~~~~~~~~^~~
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9/process/deprecated.html#zero-length-and-one-element-arrays
Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/109
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
1 file changed
