| Message ID | 20211112002706.453289-2-marijn.suijten@somainline.org (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | backlight: qcom-wled: fix and solidify handling of enabled-strings | expand |
On Fri, Nov 12, 2021 at 01:26:54AM +0100, Marijn Suijten wrote: > The strings passed in DT may possibly cause out-of-bounds register > accesses and should be validated before use. > > Fixes: 775d2ffb4af6 ("backlight: qcom-wled: Restructure the driver for WLED3") > Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org> > Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Daniel.
diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c index d094299c2a48..8a42ed89c59c 100644 --- a/drivers/video/backlight/qcom-wled.c +++ b/drivers/video/backlight/qcom-wled.c @@ -1528,12 +1528,28 @@ static int wled_configure(struct wled *wled) string_len = of_property_count_elems_of_size(dev->of_node, "qcom,enabled-strings", sizeof(u32)); - if (string_len > 0) + if (string_len > 0) { + if (string_len > wled->max_string_count) { + dev_err(dev, "Cannot have more than %d strings\n", + wled->max_string_count); + return -EINVAL; + } + of_property_read_u32_array(dev->of_node, "qcom,enabled-strings", wled->cfg.enabled_strings, sizeof(u32)); + for (i = 0; i < string_len; ++i) { + if (wled->cfg.enabled_strings[i] >= wled->max_string_count) { + dev_err(dev, + "qcom,enabled-strings index %d at %d is out of bounds\n", + wled->cfg.enabled_strings[i], i); + return -EINVAL; + } + } + } + return 0; }
The strings passed in DT may possibly cause out-of-bounds register accesses and should be validated before use. Fixes: 775d2ffb4af6 ("backlight: qcom-wled: Restructure the driver for WLED3") Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org> --- drivers/video/backlight/qcom-wled.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) -- 2.33.0