2023-11-02 00:38:12

by Ping-Ke Shih

[permalink] [raw]
Subject: [PATCH] wifi: rtw89: coex: use struct assignment to replace memcpy() to append TDMA content

To notify firmware TDMA timeslot assignment, append TDMA parameters when
sending policy H2C firmware command. However, compiler warns we do memcpy()
data to val[] field of TLV struct. To avoid this, assign the struct value
with simple '=' instead. Compile tested only.

rtw89/coex.c: In function '_append_tdma':
drivers/net/wireless/realtek/rtw89/coex.c:1585:17:
warning: writing 8 bytes into a region of size 0 [-Wstringop-overflow=]
1585 | memcpy(&v3->tdma, &dm->tdma, sizeof(v3->tdma));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from drivers/net/wireless/realtek/rtw89/coex.h:8,
from drivers/net/wireless/realtek/rtw89/coex.c:5:
drivers/net/wireless/realtek/rtw89/core.h:2703:37:
note: at offset [5714, 71249] into destination object 'ver' of size 8
2703 | const struct rtw89_btc_ver *ver;
| ^~~
drivers/net/wireless/realtek/rtw89/coex.c:1579:17:
warning: writing 8 bytes into a region of size 0 [-Wstringop-overflow=]
1579 | memcpy(v, &dm->tdma, sizeof(*v));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/wireless/realtek/rtw89/core.h:2703:37:
note: at offset [5710, 71245] into destination object 'ver' of size 8
2703 | const struct rtw89_btc_ver *ver;
| ^~~

Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Ping-Ke Shih <[email protected]>
---
drivers/net/wireless/realtek/rtw89/coex.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw89/coex.c b/drivers/net/wireless/realtek/rtw89/coex.c
index bdcc172639e4..b842cd9a86f8 100644
--- a/drivers/net/wireless/realtek/rtw89/coex.c
+++ b/drivers/net/wireless/realtek/rtw89/coex.c
@@ -1576,13 +1576,13 @@ static void _append_tdma(struct rtw89_dev *rtwdev)
if (ver->fcxtdma == 1) {
v = (struct rtw89_btc_fbtc_tdma *)&tlv->val[0];
tlv->len = sizeof(*v);
- memcpy(v, &dm->tdma, sizeof(*v));
+ *v = dm->tdma;
btc->policy_len += BTC_TLV_HDR_LEN + sizeof(*v);
} else {
tlv->len = sizeof(*v3);
v3 = (struct rtw89_btc_fbtc_tdma_v3 *)&tlv->val[0];
v3->fver = ver->fcxtdma;
- memcpy(&v3->tdma, &dm->tdma, sizeof(v3->tdma));
+ v3->tdma = dm->tdma;
btc->policy_len += BTC_TLV_HDR_LEN + sizeof(*v3);
}

--
2.25.1