malformed firmware file can cause out-of-bound access and crash during dsm_param bin loading. - add MIN/MAX param size to avoid out-of-bound access. - read start addr and size of param and check bound. - add condition that fw->size > param_size + _PAYLOAD_OFFSET to confirm enough data.

Signed-off-by: Steve Lee steves.lee@maximintegrated.com ---

Change log v2: * add condtion that param_size + _PAYLOAD_OFFSET is less than fw->size to confirm enough data * remove unintended code

sound/soc/codecs/max98390.c | 24 ++++++++++++++++++++---- sound/soc/codecs/max98390.h | 3 ++- 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/sound/soc/codecs/max98390.c b/sound/soc/codecs/max98390.c index be7cd0aeb6a6..0d63ebfbff2f 100644 --- a/sound/soc/codecs/max98390.c +++ b/sound/soc/codecs/max98390.c @@ -754,6 +754,7 @@ static struct snd_soc_dai_driver max98390_dai[] = { static int max98390_dsm_init(struct snd_soc_component *component) { int ret; + int param_size, param_start_addr; char filename[128]; const char *vendor, *product; struct max98390_priv *max98390 = @@ -780,14 +781,29 @@ static int max98390_dsm_init(struct snd_soc_component *component) dev_dbg(component->dev, "max98390: param fw size %zd\n", fw->size); + if (fw->size < MAX98390_DSM_PARAM_MIN_SIZE) { + dev_err(component->dev, + "param fw is invalid.\n"); + goto err_alloc; + } dsm_param = (char *)fw->data; + param_start_addr = (dsm_param[0] & 0xff) | (dsm_param[1] & 0xff) << 8; + param_size = (dsm_param[2] & 0xff) | (dsm_param[3] & 0xff) << 8; + if (param_size > MAX98390_DSM_PARAM_MAX_SIZE || + param_start_addr < DSM_STBASS_HPF_B0_BYTE0 || + fw->size < param_size + MAX98390_DSM_PAYLOAD_OFFSET) { + dev_err(component->dev, + "param fw is invalid.\n"); + goto err_alloc; + } + regmap_write(max98390->regmap, MAX98390_R203A_AMP_EN, 0x80); dsm_param += MAX98390_DSM_PAYLOAD_OFFSET; - regmap_bulk_write(max98390->regmap, DSM_EQ_BQ1_B0_BYTE0, - dsm_param, - fw->size - MAX98390_DSM_PAYLOAD_OFFSET); - release_firmware(fw); + regmap_bulk_write(max98390->regmap, param_start_addr, + dsm_param, param_size); regmap_write(max98390->regmap, MAX98390_R23E1_DSP_GLOBAL_EN, 0x01);

+err_alloc: + release_firmware(fw); err: return ret; } diff --git a/sound/soc/codecs/max98390.h b/sound/soc/codecs/max98390.h index f59cb114d957..5f444e7779b0 100644 --- a/sound/soc/codecs/max98390.h +++ b/sound/soc/codecs/max98390.h @@ -650,7 +650,8 @@

/* DSM register offset */ #define MAX98390_DSM_PAYLOAD_OFFSET 16 -#define MAX98390_DSM_PAYLOAD_OFFSET_2 495 +#define MAX98390_DSM_PARAM_MAX_SIZE 770 +#define MAX98390_DSM_PARAM_MIN_SIZE 670

struct max98390_priv { struct regmap *regmap;