On 2019/7/25 23:52, Takashi Iwai wrote:
On Thu, 25 Jul 2019 10:27:33 +0200, Jia-Ju Bai wrote:In build_adc_controls(), there is an if statement on line 773 to check whether ak->adc_info is NULL: if (! ak->adc_info || ! ak->adc_info[mixer_ch].switch_name) When ak->adc_info is NULL, it is used on line 792: knew.name = ak->adc_info[mixer_ch].selector_name; Thus, a possible null-pointer dereference may occur. To fix this bug, referring to lines 773 and 774, ak->adc_info and ak->adc_info[mixer_ch].selector_name are checked before being used. This bug is found by a static analysis tool STCheck written by us. Signed-off-by: Jia-Ju Bai <[email protected]> --- sound/i2c/other/ak4xxx-adda.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/sound/i2c/other/ak4xxx-adda.c b/sound/i2c/other/ak4xxx-adda.c index 5f59316f982a..9a891470e84a 100644 --- a/sound/i2c/other/ak4xxx-adda.c +++ b/sound/i2c/other/ak4xxx-adda.c @@ -775,11 +775,13 @@ static int build_adc_controls(struct snd_akm4xxx *ak) return err;memset(&knew, 0, sizeof(knew));- knew.name = ak->adc_info[mixer_ch].selector_name; - if (!knew.name) { + if (! ak->adc_info || + ! ak->adc_info[mixer_ch].selector_name) { knew.name = "Capture Channel"; knew.index = mixer_ch + ak->idx_offset * 2; } + else + knew.name = ak->adc_info[mixer_ch].selector_name;knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;knew.info = ak4xxx_capture_source_info;The code change itself looks good, but please follow the standard coding style. In short: please run checkpatch.pl, fix errors (some warnings may be ignored) and resubmit.
Okay, thanks for the advice. I will send a v2 patch. Best wishes, Jia-Ju Bai
