6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Devyn Liu <liudingyuan@xxxxxxxxxx> [ Upstream commit 5127c42c77de18651aa9e8e0a3ced190103b449c ] If the value of max_speed_hz is 0, it may cause a division by zero error in hisi_calc_effective_speed(). The value of max_speed_hz is provided by firmware. Firmware is generally considered as a trusted domain. However, as division by zero errors can cause system failure, for defense measure, the value of max_speed is validated here. So 0 is regarded as invalid and an error code is returned. Signed-off-by: Devyn Liu <liudingyuan@xxxxxxxxxx> Reviewed-by: Jay Fang <f.fangjian@xxxxxxxxxx> Link: https://patch.msgid.link/20240730032040.3156393-3-liudingyuan@xxxxxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/spi/spi-hisi-kunpeng.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/spi/spi-hisi-kunpeng.c b/drivers/spi/spi-hisi-kunpeng.c index 6910b4d4c427..16054695bdb0 100644 --- a/drivers/spi/spi-hisi-kunpeng.c +++ b/drivers/spi/spi-hisi-kunpeng.c @@ -481,6 +481,9 @@ static int hisi_spi_probe(struct platform_device *pdev) return -EINVAL; } + if (host->max_speed_hz == 0) + return dev_err_probe(dev, -EINVAL, "spi-max-frequency can't be 0\n"); + ret = device_property_read_u16(dev, "num-cs", &host->num_chipselect); if (ret) -- 2.43.0
