[PATCH 3.16 035/157] staging: rtl8712: uninitialized memory in read_bbreg_hdl()

[Ben Hutchings]

3.16.72-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 22c971db7dd4b0ad8dd88e99c407f7a1f4231a2e upstream.

Colin King reported a bug in read_bbreg_hdl():

	memcpy(pcmd->rsp, (u8 *)&val, pcmd->rspsz);

The problem is that "val" is uninitialized.

This code is obviously not useful, but so far as I can tell
"pcmd->cmdcode" is never GEN_CMD_CODE(_Read_BBREG) so it's not harmful
either.  For now the easiest fix is to just call r8712_free_cmd_obj()
and return.

Fixes: 2865d42c78a9 ("staging: r8712u: Add the new driver to the mainline kernel")
Reported-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/staging/rtl8712/rtl8712_cmd.c | 10 +---------
 drivers/staging/rtl8712/rtl8712_cmd.h |  2 +-
 2 files changed, 2 insertions(+), 10 deletions(-)

--- a/drivers/staging/rtl8712/rtl8712_cmd.c
+++ b/drivers/staging/rtl8712/rtl8712_cmd.c
@@ -155,19 +155,11 @@ static u8 write_macreg_hdl(struct _adapt
 
 static u8 read_bbreg_hdl(struct _adapter *padapter, u8 *pbuf)
 {
-	u32 val;
-	void (*pcmd_callback)(struct _adapter *dev, struct cmd_obj	*pcmd);
 	struct readBB_parm *prdbbparm;
 	struct cmd_obj *pcmd  = (struct cmd_obj *)pbuf;
 
 	prdbbparm = (struct readBB_parm *)pcmd->parmbuf;
-	if (pcmd->rsp && pcmd->rspsz > 0)
-		memcpy(pcmd->rsp, (u8 *)&val, pcmd->rspsz);
-	pcmd_callback = cmd_callback[pcmd->cmdcode].callback;
-	if (pcmd_callback == NULL)
-		r8712_free_cmd_obj(pcmd);
-	else
-		pcmd_callback(padapter, pcmd);
+	r8712_free_cmd_obj(pcmd);
 	return H2C_SUCCESS;
 }
 
--- a/drivers/staging/rtl8712/rtl8712_cmd.h
+++ b/drivers/staging/rtl8712/rtl8712_cmd.h
@@ -152,7 +152,7 @@ enum rtl8712_h2c_cmd {
 static struct _cmd_callback	cmd_callback[] = {
 	{GEN_CMD_CODE(_Read_MACREG), NULL}, /*0*/
 	{GEN_CMD_CODE(_Write_MACREG), NULL},
-	{GEN_CMD_CODE(_Read_BBREG), &r8712_getbbrfreg_cmdrsp_callback},
+	{GEN_CMD_CODE(_Read_BBREG), NULL},
 	{GEN_CMD_CODE(_Write_BBREG), NULL},
 	{GEN_CMD_CODE(_Read_RFREG), &r8712_getbbrfreg_cmdrsp_callback},
 	{GEN_CMD_CODE(_Write_RFREG), NULL}, /*5*/