drm/radeon: enforce use of radeon_get_ib_value when reading user cmd

When ever parsing cmd buffer supplied by userspace we need to use
radeon_get_ib_value rather than directly accessing the ib as the user
cmd might not yet be copied into the ib thus the parser might read
value that does not correspond to what user is sending and possibly
allowing user to send malicious command undected.

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/evergreen_cs.c b/drivers/gpu/drm/radeon/evergreen_cs.c
index 7a44566..ee4cff5 100644
--- a/drivers/gpu/drm/radeon/evergreen_cs.c
+++ b/drivers/gpu/drm/radeon/evergreen_cs.c
@@ -2909,14 +2909,14 @@
 				return -EINVAL;
 			}
 			if (tiled) {
-				dst_offset = ib[idx+1];
+				dst_offset = radeon_get_ib_value(p, idx+1);
 				dst_offset <<= 8;
 
 				ib[idx+1] += (u32)(dst_reloc->lobj.gpu_offset >> 8);
 				p->idx += count + 7;
 			} else {
-				dst_offset = ib[idx+1];
-				dst_offset |= ((u64)(ib[idx+2] & 0xff)) << 32;
+				dst_offset = radeon_get_ib_value(p, idx+1);
+				dst_offset |= ((u64)(radeon_get_ib_value(p, idx+2) & 0xff)) << 32;
 
 				ib[idx+1] += (u32)(dst_reloc->lobj.gpu_offset & 0xfffffffc);
 				ib[idx+2] += upper_32_bits(dst_reloc->lobj.gpu_offset) & 0xff;
@@ -2954,12 +2954,12 @@
 							DRM_ERROR("bad L2T, frame to fields DMA_PACKET_COPY\n");
 							return -EINVAL;
 						}
-						dst_offset = ib[idx+1];
+						dst_offset = radeon_get_ib_value(p, idx+1);
 						dst_offset <<= 8;
-						dst2_offset = ib[idx+2];
+						dst2_offset = radeon_get_ib_value(p, idx+2);
 						dst2_offset <<= 8;
-						src_offset = ib[idx+8];
-						src_offset |= ((u64)(ib[idx+9] & 0xff)) << 32;
+						src_offset = radeon_get_ib_value(p, idx+8);
+						src_offset |= ((u64)(radeon_get_ib_value(p, idx+9) & 0xff)) << 32;
 						if ((src_offset + (count * 4)) > radeon_bo_size(src_reloc->robj)) {
 							dev_warn(p->dev, "DMA L2T, frame to fields src buffer too small (%llu %lu)\n",
 								 src_offset + (count * 4), radeon_bo_size(src_reloc->robj));
@@ -3014,12 +3014,12 @@
 							DRM_ERROR("bad L2T, broadcast DMA_PACKET_COPY\n");
 							return -EINVAL;
 						}
-						dst_offset = ib[idx+1];
+						dst_offset = radeon_get_ib_value(p, idx+1);
 						dst_offset <<= 8;
-						dst2_offset = ib[idx+2];
+						dst2_offset = radeon_get_ib_value(p, idx+2);
 						dst2_offset <<= 8;
-						src_offset = ib[idx+8];
-						src_offset |= ((u64)(ib[idx+9] & 0xff)) << 32;
+						src_offset = radeon_get_ib_value(p, idx+8);
+						src_offset |= ((u64)(radeon_get_ib_value(p, idx+9) & 0xff)) << 32;
 						if ((src_offset + (count * 4)) > radeon_bo_size(src_reloc->robj)) {
 							dev_warn(p->dev, "DMA L2T, broadcast src buffer too small (%llu %lu)\n",
 								 src_offset + (count * 4), radeon_bo_size(src_reloc->robj));
@@ -3046,22 +3046,22 @@
 						/* detile bit */
 						if (idx_value & (1 << 31)) {
 							/* tiled src, linear dst */
-							src_offset = ib[idx+1];
+							src_offset = radeon_get_ib_value(p, idx+1);
 							src_offset <<= 8;
 							ib[idx+1] += (u32)(src_reloc->lobj.gpu_offset >> 8);
 
-							dst_offset = ib[idx+7];
-							dst_offset |= ((u64)(ib[idx+8] & 0xff)) << 32;
+							dst_offset = radeon_get_ib_value(p, idx+7);
+							dst_offset |= ((u64)(radeon_get_ib_value(p, idx+8) & 0xff)) << 32;
 							ib[idx+7] += (u32)(dst_reloc->lobj.gpu_offset & 0xfffffffc);
 							ib[idx+8] += upper_32_bits(dst_reloc->lobj.gpu_offset) & 0xff;
 						} else {
 							/* linear src, tiled dst */
-							src_offset = ib[idx+7];
-							src_offset |= ((u64)(ib[idx+8] & 0xff)) << 32;
+							src_offset = radeon_get_ib_value(p, idx+7);
+							src_offset |= ((u64)(radeon_get_ib_value(p, idx+8) & 0xff)) << 32;
 							ib[idx+7] += (u32)(src_reloc->lobj.gpu_offset & 0xfffffffc);
 							ib[idx+8] += upper_32_bits(src_reloc->lobj.gpu_offset) & 0xff;
 
-							dst_offset = ib[idx+1];
+							dst_offset = radeon_get_ib_value(p, idx+1);
 							dst_offset <<= 8;
 							ib[idx+1] += (u32)(dst_reloc->lobj.gpu_offset >> 8);
 						}
@@ -3098,12 +3098,12 @@
 							DRM_ERROR("bad L2T, broadcast DMA_PACKET_COPY\n");
 							return -EINVAL;
 						}
-						dst_offset = ib[idx+1];
+						dst_offset = radeon_get_ib_value(p, idx+1);
 						dst_offset <<= 8;
-						dst2_offset = ib[idx+2];
+						dst2_offset = radeon_get_ib_value(p, idx+2);
 						dst2_offset <<= 8;
-						src_offset = ib[idx+8];
-						src_offset |= ((u64)(ib[idx+9] & 0xff)) << 32;
+						src_offset = radeon_get_ib_value(p, idx+8);
+						src_offset |= ((u64)(radeon_get_ib_value(p, idx+9) & 0xff)) << 32;
 						if ((src_offset + (count * 4)) > radeon_bo_size(src_reloc->robj)) {
 							dev_warn(p->dev, "DMA L2T, broadcast src buffer too small (%llu %lu)\n",
 								 src_offset + (count * 4), radeon_bo_size(src_reloc->robj));
@@ -3135,22 +3135,22 @@
 						/* detile bit */
 						if (idx_value & (1 << 31)) {
 							/* tiled src, linear dst */
-							src_offset = ib[idx+1];
+							src_offset = radeon_get_ib_value(p, idx+1);
 							src_offset <<= 8;
 							ib[idx+1] += (u32)(src_reloc->lobj.gpu_offset >> 8);
 
-							dst_offset = ib[idx+7];
-							dst_offset |= ((u64)(ib[idx+8] & 0xff)) << 32;
+							dst_offset = radeon_get_ib_value(p, idx+7);
+							dst_offset |= ((u64)(radeon_get_ib_value(p, idx+8) & 0xff)) << 32;
 							ib[idx+7] += (u32)(dst_reloc->lobj.gpu_offset & 0xfffffffc);
 							ib[idx+8] += upper_32_bits(dst_reloc->lobj.gpu_offset) & 0xff;
 						} else {
 							/* linear src, tiled dst */
-							src_offset = ib[idx+7];
-							src_offset |= ((u64)(ib[idx+8] & 0xff)) << 32;
+							src_offset = radeon_get_ib_value(p, idx+7);
+							src_offset |= ((u64)(radeon_get_ib_value(p, idx+8) & 0xff)) << 32;
 							ib[idx+7] += (u32)(src_reloc->lobj.gpu_offset & 0xfffffffc);
 							ib[idx+8] += upper_32_bits(src_reloc->lobj.gpu_offset) & 0xff;
 
-							dst_offset = ib[idx+1];
+							dst_offset = radeon_get_ib_value(p, idx+1);
 							dst_offset <<= 8;
 							ib[idx+1] += (u32)(dst_reloc->lobj.gpu_offset >> 8);
 						}
@@ -3176,10 +3176,10 @@
 					switch (misc) {
 					case 0:
 						/* L2L, byte */
-						src_offset = ib[idx+2];
-						src_offset |= ((u64)(ib[idx+4] & 0xff)) << 32;
-						dst_offset = ib[idx+1];
-						dst_offset |= ((u64)(ib[idx+3] & 0xff)) << 32;
+						src_offset = radeon_get_ib_value(p, idx+2);
+						src_offset |= ((u64)(radeon_get_ib_value(p, idx+4) & 0xff)) << 32;
+						dst_offset = radeon_get_ib_value(p, idx+1);
+						dst_offset |= ((u64)(radeon_get_ib_value(p, idx+3) & 0xff)) << 32;
 						if ((src_offset + count) > radeon_bo_size(src_reloc->robj)) {
 							dev_warn(p->dev, "DMA L2L, byte src buffer too small (%llu %lu)\n",
 								 src_offset + count, radeon_bo_size(src_reloc->robj));
@@ -3216,12 +3216,12 @@
 							DRM_ERROR("bad L2L, dw, broadcast DMA_PACKET_COPY\n");
 							return -EINVAL;
 						}
-						dst_offset = ib[idx+1];
-						dst_offset |= ((u64)(ib[idx+4] & 0xff)) << 32;
-						dst2_offset = ib[idx+2];
-						dst2_offset |= ((u64)(ib[idx+5] & 0xff)) << 32;
-						src_offset = ib[idx+3];
-						src_offset |= ((u64)(ib[idx+6] & 0xff)) << 32;
+						dst_offset = radeon_get_ib_value(p, idx+1);
+						dst_offset |= ((u64)(radeon_get_ib_value(p, idx+4) & 0xff)) << 32;
+						dst2_offset = radeon_get_ib_value(p, idx+2);
+						dst2_offset |= ((u64)(radeon_get_ib_value(p, idx+5) & 0xff)) << 32;
+						src_offset = radeon_get_ib_value(p, idx+3);
+						src_offset |= ((u64)(radeon_get_ib_value(p, idx+6) & 0xff)) << 32;
 						if ((src_offset + (count * 4)) > radeon_bo_size(src_reloc->robj)) {
 							dev_warn(p->dev, "DMA L2L, dw, broadcast src buffer too small (%llu %lu)\n",
 								 src_offset + (count * 4), radeon_bo_size(src_reloc->robj));
@@ -3251,10 +3251,10 @@
 					}
 				} else {
 					/* L2L, dw */
-					src_offset = ib[idx+2];
-					src_offset |= ((u64)(ib[idx+4] & 0xff)) << 32;
-					dst_offset = ib[idx+1];
-					dst_offset |= ((u64)(ib[idx+3] & 0xff)) << 32;
+					src_offset = radeon_get_ib_value(p, idx+2);
+					src_offset |= ((u64)(radeon_get_ib_value(p, idx+4) & 0xff)) << 32;
+					dst_offset = radeon_get_ib_value(p, idx+1);
+					dst_offset |= ((u64)(radeon_get_ib_value(p, idx+3) & 0xff)) << 32;
 					if ((src_offset + (count * 4)) > radeon_bo_size(src_reloc->robj)) {
 						dev_warn(p->dev, "DMA L2L, dw src buffer too small (%llu %lu)\n",
 							 src_offset + (count * 4), radeon_bo_size(src_reloc->robj));
@@ -3279,8 +3279,8 @@
 				DRM_ERROR("bad DMA_PACKET_CONSTANT_FILL\n");
 				return -EINVAL;
 			}
-			dst_offset = ib[idx+1];
-			dst_offset |= ((u64)(ib[idx+3] & 0x00ff0000)) << 16;
+			dst_offset = radeon_get_ib_value(p, idx+1);
+			dst_offset |= ((u64)(radeon_get_ib_value(p, idx+3) & 0x00ff0000)) << 16;
 			if ((dst_offset + (count * 4)) > radeon_bo_size(dst_reloc->robj)) {
 				dev_warn(p->dev, "DMA constant fill buffer too small (%llu %lu)\n",
 					 dst_offset, radeon_bo_size(dst_reloc->robj));