Re: [PATCH] drm/amdgpu: validate the parameters of bo mapping operations more clearly

[Christian König]

Am 12.04.24 um 09:35 schrieb xinhui pan:

Verify the parameters of
amdgpu_vm_bo_(map/replace_map/clearing_mappings) in one common place.

Reported-by: Vlad Stolyarov <he...@google.com>
Suggested-by: Christian König <christian.koe...@amd.com>
Signed-off-by: xinhui pan <xinhui....@amd.com>

Reviewed-by: Christian König <christian.koe...@amd.com>

---
  drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 72 ++++++++++++++++----------
  1 file changed, 46 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 8af3f0fd3073..4e2391c83d7c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1647,6 +1647,37 @@ static void amdgpu_vm_bo_insert_map(struct amdgpu_device 
*adev,
        trace_amdgpu_vm_bo_map(bo_va, mapping);
  }

+/* Validate operation parameters to prevent potential abuse */

+static int amdgpu_vm_verify_parameters(struct amdgpu_device *adev,
+                                         struct amdgpu_bo *bo,
+                                         uint64_t saddr,
+                                         uint64_t offset,
+                                         uint64_t size)
+{
+       uint64_t tmp, lpfn;
+
+       if (saddr & AMDGPU_GPU_PAGE_MASK
+           || offset & AMDGPU_GPU_PAGE_MASK
+           || size & AMDGPU_GPU_PAGE_MASK)
+               return -EINVAL;
+
+       if (check_add_overflow(saddr, size, &tmp)
+           || check_add_overflow(offset, size, &tmp)
+           || size == 0 /* which also leads to end < begin */)
+               return -EINVAL;
+
+       /* make sure object fit at this offset */
+       if (bo && offset + size > amdgpu_bo_size(bo))
+               return -EINVAL;
+
+       /* Ensure last pfn not exceed max_pfn */
+       lpfn = (saddr + size - 1) >> AMDGPU_GPU_PAGE_SHIFT;
+       if (lpfn >= adev->vm_manager.max_pfn)
+               return -EINVAL;
+
+       return 0;
+}
+
  /**
   * amdgpu_vm_bo_map - map bo inside a vm
   *
@@ -1673,21 +1704,14 @@ int amdgpu_vm_bo_map(struct amdgpu_device *adev,
        struct amdgpu_bo *bo = bo_va->base.bo;
        struct amdgpu_vm *vm = bo_va->base.vm;
        uint64_t eaddr;
+       int r;

- /* validate the parameters */

-       if (saddr & ~PAGE_MASK || offset & ~PAGE_MASK || size & ~PAGE_MASK)
-               return -EINVAL;
-       if (saddr + size <= saddr || offset + size <= offset)
-               return -EINVAL;
-
-       /* make sure object fit at this offset */
-       eaddr = saddr + size - 1;
-       if ((bo && offset + size > amdgpu_bo_size(bo)) ||
-           (eaddr >= adev->vm_manager.max_pfn << AMDGPU_GPU_PAGE_SHIFT))
-               return -EINVAL;
+       r = amdgpu_vm_verify_parameters(adev, bo, saddr, offset, size);
+       if (r)
+               return r;

saddr /= AMDGPU_GPU_PAGE_SIZE;

-       eaddr /= AMDGPU_GPU_PAGE_SIZE;
+       eaddr = saddr + (size - 1) / AMDGPU_GPU_PAGE_SIZE;

tmp = amdgpu_vm_it_iter_first(&vm->va, saddr, eaddr);

        if (tmp) {
@@ -1740,17 +1764,9 @@ int amdgpu_vm_bo_replace_map(struct amdgpu_device *adev,
        uint64_t eaddr;
        int r;

- /* validate the parameters */

-       if (saddr & ~PAGE_MASK || offset & ~PAGE_MASK || size & ~PAGE_MASK)
-               return -EINVAL;
-       if (saddr + size <= saddr || offset + size <= offset)
-               return -EINVAL;
-
-       /* make sure object fit at this offset */
-       eaddr = saddr + size - 1;
-       if ((bo && offset + size > amdgpu_bo_size(bo)) ||
-           (eaddr >= adev->vm_manager.max_pfn << AMDGPU_GPU_PAGE_SHIFT))
-               return -EINVAL;
+       r = amdgpu_vm_verify_parameters(adev, bo, saddr, offset, size);
+       if (r)
+               return r;

/* Allocate all the needed memory */

        mapping = kmalloc(sizeof(*mapping), GFP_KERNEL);
@@ -1764,7 +1780,7 @@ int amdgpu_vm_bo_replace_map(struct amdgpu_device *adev,
        }

saddr /= AMDGPU_GPU_PAGE_SIZE;

-       eaddr /= AMDGPU_GPU_PAGE_SIZE;
+       eaddr = saddr + (size - 1) / AMDGPU_GPU_PAGE_SIZE;

mapping->start = saddr;

        mapping->last = eaddr;
@@ -1851,10 +1867,14 @@ int amdgpu_vm_bo_clear_mappings(struct amdgpu_device 
*adev,
        struct amdgpu_bo_va_mapping *before, *after, *tmp, *next;
        LIST_HEAD(removed);
        uint64_t eaddr;
+       int r;
+
+       r = amdgpu_vm_verify_parameters(adev, NULL, saddr, 0, size);
+       if (r)
+               return r;

- eaddr = saddr + size - 1;

        saddr /= AMDGPU_GPU_PAGE_SIZE;
-       eaddr /= AMDGPU_GPU_PAGE_SIZE;
+       eaddr = saddr + (size - 1) / AMDGPU_GPU_PAGE_SIZE;

/* Allocate all the needed memory */

        before = kzalloc(sizeof(*before), GFP_KERNEL);