[PATCH 4.14 27/49] staging: rtl8712: uninitialized memory in read_bbreg_hdl()

Greg Kroah-Hartman
2019-05-02T15:24:16Z

[ Upstream commit 22c971db7dd4b0ad8dd88e99c407f7a1f4231a2e ]

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@canonical.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
---
drivers/staging/rtl8712/rtl8712_cmd.c | 10 +---------
drivers/staging/rtl8712/rtl8712_cmd.h | 2 +-
2 files changed, 2 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/rtl8712/rtl8712_cmd.c b/drivers/staging/rtl8712/rtl8712_cmd.c
index 0104aced113e..ccda04e916c5 100644
--- a/drivers/staging/rtl8712/rtl8712_cmd.c
+++ b/drivers/staging/rtl8712/rtl8712_cmd.c
@@ -159,17 +159,9 @@ static u8 write_macreg_hdl(struct _adapter *padapter, u8 *pbuf)

static u8 read_bbreg_hdl(struct _adapter *padapter, u8 *pbuf)
{
- u32 val;
- void (*pcmd_callback)(struct _adapter *dev, struct cmd_obj *pcmd);
struct cmd_obj *pcmd = (struct cmd_obj *)pbuf;

- if (pcmd->rsp && pcmd->rspsz > 0)
- memcpy(pcmd->rsp, (u8 *)&val, pcmd->rspsz);
- pcmd_callback = cmd_callback[pcmd->cmdcode].callback;
- if (!pcmd_callback)
- r8712_free_cmd_obj(pcmd);
- else
- pcmd_callback(padapter, pcmd);
+ r8712_free_cmd_obj(pcmd);
return H2C_SUCCESS;
}

diff --git a/drivers/staging/rtl8712/rtl8712_cmd.h b/drivers/staging/rtl8712/rtl8712_cmd.h
index 67e9e910aef9..d10a59d4a550 100644
--- 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*/
--
2.19.1