[RESEND PATCH v2 01/13] backlight: qcom-wled: Validate enabled string indices in DT
From: Marijn Suijten <marijn.suijten@somainline.org>
Date: 2021-11-12 00:27:18
Also in:
dri-devel, linux-arm-msm, linux-devicetree, lkml, phone-devel
Subsystem:
arm/qualcomm mailing list, backlight class/subsystem, framebuffer layer, the rest · Maintainers:
Lee Jones, Daniel Thompson, Jingoo Han, Helge Deller, Linus Torvalds
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 <redacted>
---
drivers/video/backlight/qcom-wled.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)
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; } --
2.33.0