From 6949aa0eadafec9f4e83920a798330025c049ce5 Mon Sep 17 00:00:00 2001 From: Gwan-gyeong Mun Date: Wed, 28 Dec 2022 21:22:49 +0200 Subject: [PATCH] drm/i915: Check for integer truncation on the configuration of ttm place MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit There is an impedance mismatch between the first/last valid page frame number of ttm place in unsigned and our memory/page accounting in unsigned long. As the object size is under the control of userspace, we have to be prudent and catch the conversion errors. To catch the implicit truncation as we switch from unsigned long to unsigned, we use overflows_type check and report E2BIG or overflow_type prior to the operation. v3: Not to change execution inside a macro. (Mauro) Add safe_conversion_gem_bug_on() macro and remove temporal SAFE_CONVERSION() macro. v4: Fix unhandled GEM_BUG_ON() macro call from safe_conversion_gem_bug_on() v6: Fix to follow general use case for GEM_BUG_ON(). (Jani) v7: Fix to use WARN_ON() macro where GEM_BUG_ON() macro was used. (Jani) v8: Replace safe_conversion() with check_assign() (Kees) v14: Split one macro of assignment with checking of overflow to two steps, first overflow check, and second assignment. Cc: Chris Wilson Cc: Matthew Auld Cc: Thomas Hellström Cc: Jani Nikula Signed-off-by: Gwan-gyeong Mun Reviewed-by: Nirmoy Das (v2) Reviewed-by: Mauro Carvalho Chehab (v3) Reported-by: kernel test robot Reviewed-by: Andrzej Hajda (v5) Signed-off-by: Rodrigo Vivi Link: https://patchwork.freedesktop.org/patch/msgid/20221228192252.917299-4-gwan-gyeong.mun@intel.com --- drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 3 +++ drivers/gpu/drm/i915/intel_region_ttm.c | 14 ++++++++++++++ 2 files changed, 17 insertions(+) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c index af1378d93baa..5f3abe1bb7d7 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c @@ -140,13 +140,16 @@ i915_ttm_place_from_region(const struct intel_memory_region *mr, if (flags & I915_BO_ALLOC_CONTIGUOUS) place->flags |= TTM_PL_FLAG_CONTIGUOUS; if (offset != I915_BO_INVALID_OFFSET) { + WARN_ON(overflows_type(offset >> PAGE_SHIFT, place->fpfn)); place->fpfn = offset >> PAGE_SHIFT; + WARN_ON(overflows_type(place->fpfn + (size >> PAGE_SHIFT), place->lpfn)); place->lpfn = place->fpfn + (size >> PAGE_SHIFT); } else if (mr->io_size && mr->io_size < mr->total) { if (flags & I915_BO_ALLOC_GPU_ONLY) { place->flags |= TTM_PL_FLAG_TOPDOWN; } else { place->fpfn = 0; + WARN_ON(overflows_type(mr->io_size >> PAGE_SHIFT, place->lpfn)); place->lpfn = mr->io_size >> PAGE_SHIFT; } } diff --git a/drivers/gpu/drm/i915/intel_region_ttm.c b/drivers/gpu/drm/i915/intel_region_ttm.c index cf89d0c2a2d9..7f0ec35af098 100644 --- a/drivers/gpu/drm/i915/intel_region_ttm.c +++ b/drivers/gpu/drm/i915/intel_region_ttm.c @@ -209,13 +209,25 @@ intel_region_ttm_resource_alloc(struct intel_memory_region *mem, if (flags & I915_BO_ALLOC_CONTIGUOUS) place.flags |= TTM_PL_FLAG_CONTIGUOUS; if (offset != I915_BO_INVALID_OFFSET) { + if (WARN_ON(overflows_type(offset >> PAGE_SHIFT, place.fpfn))) { + ret = -E2BIG; + goto out; + } place.fpfn = offset >> PAGE_SHIFT; + if (WARN_ON(overflows_type(place.fpfn + (size >> PAGE_SHIFT), place.lpfn))) { + ret = -E2BIG; + goto out; + } place.lpfn = place.fpfn + (size >> PAGE_SHIFT); } else if (mem->io_size && mem->io_size < mem->total) { if (flags & I915_BO_ALLOC_GPU_ONLY) { place.flags |= TTM_PL_FLAG_TOPDOWN; } else { place.fpfn = 0; + if (WARN_ON(overflows_type(mem->io_size >> PAGE_SHIFT, place.lpfn))) { + ret = -E2BIG; + goto out; + } place.lpfn = mem->io_size >> PAGE_SHIFT; } } @@ -224,6 +236,8 @@ intel_region_ttm_resource_alloc(struct intel_memory_region *mem, mock_bo.bdev = &mem->i915->bdev; ret = man->func->alloc(man, &mock_bo, &place, &res); + +out: if (ret == -ENOSPC) ret = -ENXIO; if (!ret) -- 2.34.1