Am 05.03.19 um 22:17 schrieb Sean Young: > On Fri, Dec 21, 2018 at 09:24:46AM +0100, Matthias Schwarzott wrote: >> Am 21.12.18 um 05:54 schrieb Kangjie Lu: >>> 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> >> >> Reviewed-by: Matthias Schwarzott <zzam@xxxxxxxxxx> > > Unless it is tested on the actual hardware we can't apply this. This could > introduce regressions. > I tested it on a Hauppauge WinTV-HVR5500 tuning to DVB-C. Regards Matthias Tested-by: Matthias Schwarzott <zzam@xxxxxxxxxx> > Sean > >> >>> --- >>> 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, >>> >