From 7a46a4b6a5975251f1529007fe15da6734e4891c Mon Sep 17 00:00:00 2001 From: bones_was_here Date: Mon, 29 Jan 2024 16:40:48 +1000 Subject: [PATCH] IQM: fix misaligned memory access Signed-off-by: bones_was_here --- model_alias.c | 69 +++++++++++++++++++++++++++------------------------ 1 file changed, 37 insertions(+), 32 deletions(-) diff --git a/model_alias.c b/model_alias.c index 649324d1..46ede5d6 100644 --- a/model_alias.c +++ b/model_alias.c @@ -3174,7 +3174,7 @@ void Mod_INTERQUAKEMODEL_Load(model_t *mod, void *buffer, void *bufferend) const unsigned char *pbase, *pend; iqmheader_t header; skinfile_t *skinfiles; - int i, j, k, meshvertices, meshtriangles; + int i, j, k; float biggestorigin; const unsigned int *inelements; int *outelements; @@ -3375,48 +3375,53 @@ void Mod_INTERQUAKEMODEL_Load(model_t *mod, void *buffer, void *bufferend) loadmodel->submodelsurfaces_end = loadmodel->num_surfaces = header.num_meshes; loadmodel->num_textures = loadmodel->num_surfaces * loadmodel->numskins; loadmodel->num_texturesperskin = loadmodel->num_surfaces; - - meshvertices = header.num_vertexes; - meshtriangles = header.num_triangles; + loadmodel->surfmesh.num_vertices = header.num_vertexes; + loadmodel->surfmesh.num_triangles = header.num_triangles; // 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]) + (vcolor4f || vcolor4ub ? sizeof(float[4]) : 0)) + (vblendindexes && vblendweights ? meshvertices * (sizeof(unsigned short) + sizeof(unsigned char[2][4])) : 0) + 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]); + // This is only robust for C standard types! + data = (unsigned char *)Mem_Alloc(loadmodel->mempool, + loadmodel->surfmesh.num_vertices * (sizeof(float[14]) + (vcolor4f || vcolor4ub ? sizeof(float[4]) : 0)) + + loadmodel->num_bones * sizeof(float[12]) + + loadmodel->num_surfaces * sizeof(int) + + loadmodel->surfmesh.num_triangles * sizeof(int[3]) + + (loadmodel->surfmesh.num_vertices <= 65536 ? loadmodel->surfmesh.num_triangles * sizeof(unsigned short[3]) : 0) + + loadmodel->num_poses * loadmodel->num_bones * sizeof(short[7]) + + (vblendindexes && vblendweights ? loadmodel->surfmesh.num_vertices * (sizeof(unsigned short) + sizeof(unsigned char[2][4])) : 0)); + // Pointers must be taken in descending order of alignment requirement! + loadmodel->surfmesh.data_vertex3f = (float *)data; data += loadmodel->surfmesh.num_vertices * sizeof(float[3]); + loadmodel->surfmesh.data_svector3f = (float *)data; data += loadmodel->surfmesh.num_vertices * sizeof(float[3]); + loadmodel->surfmesh.data_tvector3f = (float *)data; data += loadmodel->surfmesh.num_vertices * sizeof(float[3]); + loadmodel->surfmesh.data_normal3f = (float *)data; data += loadmodel->surfmesh.num_vertices * sizeof(float[3]); + loadmodel->surfmesh.data_texcoordtexture2f = (float *)data; data += loadmodel->surfmesh.num_vertices * sizeof(float[2]); if (vcolor4f || vcolor4ub) { - loadmodel->surfmesh.data_lightmapcolor4f = (float *)data;data += meshvertices * sizeof(float[4]); + loadmodel->surfmesh.data_lightmapcolor4f = (float *)data; data += loadmodel->surfmesh.num_vertices * sizeof(float[4]); } - if (vblendindexes && vblendweights) + 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 += loadmodel->surfmesh.num_triangles * sizeof(int[3]); + loadmodel->data_poses7s = (short *)data; data += loadmodel->num_poses * loadmodel->num_bones * sizeof(short[7]); + if (loadmodel->surfmesh.num_vertices <= 65536) { - 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->surfmesh.data_element3s = (unsigned short *)data; data += loadmodel->surfmesh.num_triangles * sizeof(unsigned short[3]); } - 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); if (vblendindexes && vblendweights) { loadmodel->surfmesh.num_blends = 0; - 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->data_poses7s = (short *)data;data += loadmodel->num_poses * loadmodel->num_bones * sizeof(short[7]); + loadmodel->surfmesh.blends = (unsigned short *)data; data += loadmodel->surfmesh.num_vertices * sizeof(unsigned short); + loadmodel->surfmesh.data_skeletalindex4ub = (unsigned char *)data; data += loadmodel->surfmesh.num_vertices * sizeof(unsigned char[4]); + loadmodel->surfmesh.data_skeletalweight4ub = (unsigned char *)data; data += loadmodel->surfmesh.num_vertices * 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)); if (vblendindexes && vblendweights) - loadmodel->surfmesh.data_blendweights = (blendweights_t *)Mem_Alloc(loadmodel->mempool, meshvertices * sizeof(blendweights_t)); + loadmodel->surfmesh.data_blendweights = Mem_AllocType(loadmodel->mempool, blendweights_t, loadmodel->surfmesh.num_vertices * sizeof(blendweights_t)); for (i = 0;i < loadmodel->numskins;i++) { -- 2.39.2