[PATCH v3] rtw_security: fix cast to restricted __le32

From: Jhih-Ming Huang
Date: Fri Jun 18 2021 - 14:18:14 EST


This patch fixes the sparse warning of fix cast to restricted __le32.

There was a change for replacing private CRC-32 routines with in kernel
ones.
However, the author used le32_to_cpu to convert crc32_le(), and we
should cpu_to_le32.

Ths commit also fixes the payload checking by memcmp instead of checking element
by element.

Signed-off-by: Jhih-Ming Huang <fbihjmeric@xxxxxxxxx>
---
drivers/staging/rtl8723bs/core/rtw_security.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/rtl8723bs/core/rtw_security.c b/drivers/staging/rtl8723bs/core/rtw_security.c
index a99f439328f1..97a7485f8f58 100644
--- a/drivers/staging/rtl8723bs/core/rtw_security.c
+++ b/drivers/staging/rtl8723bs/core/rtw_security.c
@@ -121,7 +121,7 @@ void rtw_wep_decrypt(struct adapter *padapter, u8 *precvframe)
arc4_crypt(ctx, payload, payload, length);

/* calculate icv and compare the icv */
- *((u32 *)crc) = le32_to_cpu(~crc32_le(~0, payload, length - 4));
+ *crc = cpu_to_le32(~crc32_le(~0, payload, length - 4));

}
}
@@ -618,10 +618,9 @@ u32 rtw_tkip_decrypt(struct adapter *padapter, u8 *precvframe)
arc4_setkey(ctx, rc4key, 16);
arc4_crypt(ctx, payload, payload, length);

- *((u32 *)crc) = le32_to_cpu(~crc32_le(~0, payload, length - 4));
+ *crc = cpu_to_le32(~crc32_le(~0, payload, length - 4));

- if (crc[3] != payload[length - 1] || crc[2] != payload[length - 2] ||
- crc[1] != payload[length - 3] || crc[0] != payload[length - 4])
+ if (memcmp(&crc, payload + length - 4, 4) != 0)
res = _FAIL;
} else {
res = _FAIL;
--
2.32.0.288