From: bones_was_here Date: Fri, 26 Jan 2024 07:20:53 +0000 (+1000) Subject: DPM: fix misaligned memory access X-Git-Url: https://git.rm.cloudns.org/?a=commitdiff_plain;h=92d1300d3a885f3447f411d1be7c4d2d531ebe6d;p=xonotic%2Fdarkplaces.git DPM: fix misaligned memory access Signed-off-by: bones_was_here --- diff --git a/model_alias.c b/model_alias.c index fc9c9313..4c87c32e 100644 --- a/model_alias.c +++ b/model_alias.c @@ -2255,33 +2255,44 @@ void Mod_DARKPLACESMODEL_Load(model_t *mod, void *buffer, void *bufferend) loadmodel->submodelsurfaces_end = loadmodel->num_surfaces = pheader->num_meshs; loadmodel->num_textures = loadmodel->num_surfaces * loadmodel->numskins; loadmodel->num_texturesperskin = loadmodel->num_surfaces; - // do most allocations as one merged chunk - data = (unsigned char *)Mem_Alloc(loadmodel->mempool, loadmodel->num_surfaces * sizeof(msurface_t) + loadmodel->num_surfaces * sizeof(int) + loadmodel->num_surfaces * loadmodel->numskins * sizeof(texture_t) + meshtriangles * sizeof(int[3]) + (meshvertices <= 65536 ? meshtriangles * sizeof(unsigned short[3]) : 0) + meshvertices * (sizeof(float[14]) + sizeof(unsigned short) + sizeof(unsigned char[2][4])) + loadmodel->num_poses * loadmodel->num_bones * sizeof(short[7]) + loadmodel->num_bones * sizeof(float[12]) + loadmodel->numskins * sizeof(animscene_t) + loadmodel->num_bones * sizeof(aliasbone_t) + loadmodel->numframes * sizeof(animscene_t)); - loadmodel->data_surfaces = (msurface_t *)data;data += loadmodel->num_surfaces * sizeof(msurface_t); - loadmodel->modelsurfaces_sorted = (int *)data;data += loadmodel->num_surfaces * sizeof(int); - loadmodel->data_textures = (texture_t *)data;data += loadmodel->num_surfaces * loadmodel->numskins * sizeof(texture_t); loadmodel->surfmesh.num_vertices = meshvertices; loadmodel->surfmesh.num_triangles = meshtriangles; - loadmodel->surfmesh.data_element3i = (int *)data;data += meshtriangles * sizeof(int[3]); - loadmodel->surfmesh.data_vertex3f = (float *)data;data += meshvertices * sizeof(float[3]); - loadmodel->surfmesh.data_svector3f = (float *)data;data += meshvertices * sizeof(float[3]); - loadmodel->surfmesh.data_tvector3f = (float *)data;data += meshvertices * sizeof(float[3]); - loadmodel->surfmesh.data_normal3f = (float *)data;data += meshvertices * sizeof(float[3]); - loadmodel->surfmesh.data_texcoordtexture2f = (float *)data;data += meshvertices * sizeof(float[2]); - loadmodel->surfmesh.data_skeletalindex4ub = (unsigned char *)data;data += meshvertices * sizeof(unsigned char[4]); - loadmodel->surfmesh.data_skeletalweight4ub = (unsigned char *)data;data += meshvertices * sizeof(unsigned char[4]); - loadmodel->data_baseboneposeinverse = (float *)data;data += loadmodel->num_bones * sizeof(float[12]); - loadmodel->skinscenes = (animscene_t *)data;data += loadmodel->numskins * sizeof(animscene_t); - loadmodel->data_bones = (aliasbone_t *)data;data += loadmodel->num_bones * sizeof(aliasbone_t); - loadmodel->animscenes = (animscene_t *)data;data += loadmodel->numframes * sizeof(animscene_t); loadmodel->surfmesh.num_blends = 0; - loadmodel->surfmesh.blends = (unsigned short *)data;data += meshvertices * sizeof(unsigned short); + + // do most allocations as one merged chunk + // This is only robust for C standard types! + data = (unsigned char *)Mem_Alloc(loadmodel->mempool, + loadmodel->num_surfaces * sizeof(int) + + meshtriangles * sizeof(int[3]) + + (meshvertices <= 65536 ? meshtriangles * sizeof(unsigned short[3]) : 0) + + meshvertices * (sizeof(float[14]) + sizeof(unsigned short) + sizeof(unsigned char[2][4])) + + loadmodel->num_poses * loadmodel->num_bones * sizeof(short[7]) + + loadmodel->num_bones * sizeof(float[12])); + // Pointers must be taken in descending order of alignment requirement! + loadmodel->surfmesh.data_vertex3f = (float *)data; data += meshvertices * sizeof(float[3]); + loadmodel->surfmesh.data_svector3f = (float *)data; data += meshvertices * sizeof(float[3]); + loadmodel->surfmesh.data_tvector3f = (float *)data; data += meshvertices * sizeof(float[3]); + loadmodel->surfmesh.data_normal3f = (float *)data; data += meshvertices * sizeof(float[3]); + loadmodel->surfmesh.data_texcoordtexture2f = (float *)data; data += meshvertices * sizeof(float[2]); + loadmodel->data_baseboneposeinverse = (float *)data; data += loadmodel->num_bones * sizeof(float[12]); + loadmodel->modelsurfaces_sorted = (int *)data; data += loadmodel->num_surfaces * sizeof(int); + loadmodel->surfmesh.data_element3i = (int *)data; data += meshtriangles * sizeof(int[3]); + loadmodel->surfmesh.blends = (unsigned short *)data; data += meshvertices * sizeof(unsigned short); if (meshvertices <= 65536) { - loadmodel->surfmesh.data_element3s = (unsigned short *)data;data += meshtriangles * sizeof(unsigned short[3]); + loadmodel->surfmesh.data_element3s = (unsigned short *)data; data += meshtriangles * sizeof(unsigned short[3]); } - loadmodel->data_poses7s = (short *)data;data += loadmodel->num_poses * loadmodel->num_bones * sizeof(short[7]); - loadmodel->surfmesh.data_blendweights = (blendweights_t *)Mem_Alloc(loadmodel->mempool, meshvertices * sizeof(blendweights_t)); + loadmodel->data_poses7s = (short *)data; data += loadmodel->num_poses * loadmodel->num_bones * sizeof(short[7]); + loadmodel->surfmesh.data_skeletalindex4ub = (unsigned char *)data; data += meshvertices * sizeof(unsigned char[4]); + loadmodel->surfmesh.data_skeletalweight4ub = (unsigned char *)data; data += meshvertices * sizeof(unsigned char[4]); + // Struct alignment requirements could change so we can't assume them here + // otherwise a safe-looking commit could introduce undefined behaviour! + loadmodel->data_surfaces = Mem_AllocType(loadmodel->mempool, msurface_t, loadmodel->num_surfaces * sizeof(msurface_t)); + loadmodel->data_textures = Mem_AllocType(loadmodel->mempool, texture_t, loadmodel->num_surfaces * loadmodel->numskins * sizeof(texture_t)); + loadmodel->skinscenes = Mem_AllocType(loadmodel->mempool, animscene_t, loadmodel->numskins * sizeof(animscene_t)); + loadmodel->data_bones = Mem_AllocType(loadmodel->mempool, aliasbone_t, loadmodel->num_bones * sizeof(aliasbone_t)); + loadmodel->animscenes = Mem_AllocType(loadmodel->mempool, animscene_t, loadmodel->numframes * sizeof(animscene_t)); + loadmodel->surfmesh.data_blendweights = Mem_AllocType(loadmodel->mempool, blendweights_t, meshvertices * sizeof(blendweights_t)); for (i = 0;i < loadmodel->numskins;i++) { @@ -2488,7 +2499,7 @@ void Mod_DARKPLACESMODEL_Load(model_t *mod, void *buffer, void *bufferend) Mod_ValidateElements(loadmodel->surfmesh.data_element3i + surface->num_firsttriangle * 3, loadmodel->surfmesh.data_element3s + surface->num_firsttriangle * 3, surface->num_triangles, surface->num_firstvertex, surface->num_vertices, __FILE__, __LINE__); } if (loadmodel->surfmesh.num_blends < meshvertices) - loadmodel->surfmesh.data_blendweights = (blendweights_t *)Mem_Realloc(loadmodel->mempool, loadmodel->surfmesh.data_blendweights, loadmodel->surfmesh.num_blends * sizeof(blendweights_t)); + loadmodel->surfmesh.data_blendweights = Mem_ReallocType(loadmodel->mempool, loadmodel->surfmesh.data_blendweights, blendweights_t, loadmodel->surfmesh.num_blends * sizeof(blendweights_t)); Z_Free(bonepose); Mod_FreeSkinFiles(skinfiles); Mod_MakeSortedSurfaces(loadmodel);