[PATCH 04/10] backlight: qcom-wled: Validate enabled string indices in DT
From: Marijn Suijten <marijn.suijten@somainline.org>
Date: 2021-10-04 19:27:52
Also in:
dri-devel, linux-arm-msm, 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 | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index 29910e603c42..27e8949c7922 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c@@ -1526,6 +1526,12 @@ static int wled_configure(struct wled *wled) "qcom,enabled-strings", sizeof(u32)); 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; + } + rc = of_property_read_u32_array(dev->of_node, "qcom,enabled-strings", wled->cfg.enabled_strings,
@@ -1537,6 +1543,14 @@ static int wled_configure(struct wled *wled) return -EINVAL; } + 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; + } + } + cfg->num_strings = string_len; }
--
2.33.0