[PATCH v2] media: si2165: fix a missing check of return value

From: Kangjie Lu
Date: Thu Dec 20 2018 - 23:55:57 EST


si2165_readreg8() may fail. Looking into si2165_readreg8(), we will find
that "val_tmp" will be an uninitialized value when regmap_read() fails.
"val_tmp" is then assigned to "val". So if si2165_readreg8() fails,
"val" will be a random value. Further use will lead to undefined
behaviors. The fix checks if si2165_readreg8() fails, and if so, returns
its error code upstream.

Signed-off-by: Kangjie Lu <kjlu@xxxxxxx>
---
drivers/media/dvb-frontends/si2165.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/media/dvb-frontends/si2165.c b/drivers/media/dvb-frontends/si2165.c
index feacd8da421d..d55d8f169dca 100644
--- a/drivers/media/dvb-frontends/si2165.c
+++ b/drivers/media/dvb-frontends/si2165.c
@@ -275,18 +275,20 @@ static u32 si2165_get_fe_clk(struct si2165_state *state)

static int si2165_wait_init_done(struct si2165_state *state)
{
- int ret = -EINVAL;
+ int ret;
u8 val = 0;
int i;

for (i = 0; i < 3; ++i) {
- si2165_readreg8(state, REG_INIT_DONE, &val);
+ ret = si2165_readreg8(state, REG_INIT_DONE, &val);
+ if (ret < 0)
+ return ret;
if (val == 0x01)
return 0;
usleep_range(1000, 50000);
}
dev_err(&state->client->dev, "init_done was not set\n");
- return ret;
+ return -EINVAL;
}

static int si2165_upload_firmware_block(struct si2165_state *state,
--
2.17.2 (Apple Git-113)