Just sanity check that the value we deduce from the stolen memory register fits within the kernel's dma_addr_t and doesn't overflow.
Signed-off-by: Chris Wilson <[email protected]> Cc: Paulo Zanoni <[email protected]> Cc: Ville Syrjälä <[email protected]> --- drivers/gpu/drm/i915/i915_gem_stolen.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c index 42bbc4b04fd6..4f1f3090c0ed 100644 --- a/drivers/gpu/drm/i915/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c @@ -211,6 +211,14 @@ static dma_addr_t i915_stolen_to_dma(struct drm_i915_private *dev_priv) ggtt_start &= PGTBL_ADDRESS_LO_MASK; ggtt_end = ggtt_start + ggtt_total_entries(ggtt) * 4; + if (ggtt_end <= ggtt_start || + overflows_type(ggtt_end, dma_addr_t)) { + DRM_ERROR("DMA address for reserved igfx memory [%llx - %llx] does not fit within the kernel's %db dma_addr_t\n", + ggtt_start, ggtt_end, + (int)sizeof(dma_addr_t) * 8); + return 0; + } + if (ggtt_start >= stolen[0].start && ggtt_start < stolen[0].end) stolen[0].end = ggtt_start; if (ggtt_end > stolen[1].start && ggtt_end <= stolen[1].end) -- 2.11.0 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
