From: Dan Carpenter Date: Thu, 10 Sep 2020 10:07:48 +0000 (+0300) Subject: drm/vc4: hdmi: Fix off by ones in vc4_hdmi_read/write() X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=130cdec4e12836cb2d5346216902c49800a07c33;p=linux.git drm/vc4: hdmi: Fix off by ones in vc4_hdmi_read/write() The variant->registers[] has ->num_registers elements so the > comparison needs to be changes to >= to prevent an out of bounds access. Fixes: 311e305fdb4e ("drm/vc4: hdmi: Implement a register layout abstraction") Signed-off-by: Dan Carpenter Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20200910100748.GA79916@mwanda --- diff --git a/drivers/gpu/drm/vc4/vc4_hdmi_regs.h b/drivers/gpu/drm/vc4/vc4_hdmi_regs.h index a5f1354e3e067..47364bd3960dd 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi_regs.h +++ b/drivers/gpu/drm/vc4/vc4_hdmi_regs.h @@ -398,7 +398,7 @@ static inline u32 vc4_hdmi_read(struct vc4_hdmi *hdmi, const struct vc4_hdmi_variant *variant = hdmi->variant; void __iomem *base; - if (reg > variant->num_registers) { + if (reg >= variant->num_registers) { dev_warn(&hdmi->pdev->dev, "Invalid register ID %u\n", reg); return 0; @@ -424,7 +424,7 @@ static inline void vc4_hdmi_write(struct vc4_hdmi *hdmi, const struct vc4_hdmi_variant *variant = hdmi->variant; void __iomem *base; - if (reg > variant->num_registers) { + if (reg >= variant->num_registers) { dev_warn(&hdmi->pdev->dev, "Invalid register ID %u\n", reg); return;