[PATCH 2/2] staging: rtl8192e: Change state information from u16 to u8

Atul Gopinathan
2021-02-20T18:27:32Z

The "CcxRmState" field in struct "rtllib_network" is defined
as a u16 array of size 2 (so, 4 bytes in total).

But the operations performed on this array throughout the code
base (in rtl8192e/) are all in byte size 2 indicating that this
array's type was defined wrongly.

There are two situation were u16 type of this field could yield
incorrect behaviour:

1. In rtllib_rx.c:1970:
memcpy(network->CcxRmState, &info_element->data[4], 2);

Here last 2 bytes (index 4 and 5) from the info_element->data[]
array are meant to be copied into CcxRmState[].
Note that "data" array here is an array of type u8.

2. In function "update_network()" in staging/rtl8192e/rtllib_rx.c:
memcpy(dst->CcxRmState, src->CcxRmState, 2);

Here again, only 2 bytes are copied from the source state to
destination state.

There are no instances of "CcxRmState" requiring u16 data type.
Here is the output of "grep -IRn 'CcxRmState'" on the rtl8192e/
directory for reviewing:

rtllib_rx.c:1970: memcpy(network->CcxRmState, &info_element->data[4], 2);
rtllib_rx.c:1971: if (network->CcxRmState[0] != 0)
rtllib_rx.c:1975: network->MBssidMask = network->CcxRmState[1] & 0x07;
rtllib_rx.c:2520: memcpy(dst->CcxRmState, src->CcxRmState, 2);
rtllib.h:1108: u8 CcxRmState[2];

//Note: The last line of output is my commit to this patch (u8 instead
of u16).

Signed-off-by: Atul Gopinathan <atulgopinathan@gmail.com>
---
drivers/staging/rtl8192e/rtllib.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/rtl8192e/rtllib.h b/drivers/staging/rtl8192e/rtllib.h
index b84f00b8d18b..4cabaf21c1ca 100644
--- a/drivers/staging/rtl8192e/rtllib.h
+++ b/drivers/staging/rtl8192e/rtllib.h
@@ -1101,15 +1101,15 @@ struct rtllib_network {
u8 hidden_ssid[IW_ESSID_MAX_SIZE + 1];
u8 hidden_ssid_len;
struct rtllib_qos_data qos_data;

bool bWithAironetIE;
bool bCkipSupported;
bool bCcxRmEnable;
- u16 CcxRmState[2];
+ u8 CcxRmState[2];
bool bMBssidValid;
u8 MBssidMask;
u8 MBssid[ETH_ALEN];
bool bWithCcxVerNum;
u8 BssCcxVerNumber;
/* These are network statistics */
struct rtllib_rx_stats stats;
--
2.27.0