[PATCH stable 4.9 20/21] media: dvb_frontend: fix wrong cast in compat_ioctl

From: Florian Fainelli
Date: Fri Jun 05 2020 - 12:26:54 EST


From: Katsuhiro Suzuki <suzuki.katsuhiro@xxxxxxxxxxxxx>

commit 5c6c9c4830b76d851d38829611b3c3e4be0f5cdf upstream

FE_GET_PROPERTY has always failed as following situations:
- Use compatible ioctl
- The array of 'struct dtv_property' has 2 or more items

This patch fixes wrong cast to a pointer 'struct dtv_property' from a
pointer of 2nd or after item of 'struct compat_dtv_property' array.

Signed-off-by: Katsuhiro Suzuki <suzuki.katsuhiro@xxxxxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
drivers/media/dvb-core/dvb_frontend.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c
index 34f55a2ba071..740dedf03361 100644
--- a/drivers/media/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb-core/dvb_frontend.c
@@ -2081,7 +2081,7 @@ static int dvb_frontend_handle_compat_ioctl(struct file *file, unsigned int cmd,
}
for (i = 0; i < tvps->num; i++) {
err = dtv_property_process_get(
- fe, &getp, (struct dtv_property *)tvp + i, file);
+ fe, &getp, (struct dtv_property *)(tvp + i), file);
if (err < 0) {
kfree(tvp);
return err;
--
2.17.1