From 3bf5eddb89afdf690eceaa52bc4d3546ba9a5f87 Mon Sep 17 00:00:00 2001 From: Eric Soroos Date: Sun, 7 Mar 2021 12:32:12 +0100 Subject: [PATCH] Fix OOB Read in Jpeg2KDecode CVE-2021-25287,CVE-2021-25288 Conflict:NA Reference:https://github.com/python-pillow/Pillow/commit/3bf5eddb89afdf690eceaa52bc4d3546ba9a5f87 --- src/libImaging/Jpeg2KDecode.c | 33 +++++++++++++++++++++++++-------- 1 file changed, 25 insertions(+), 8 deletions(-) diff --git a/src/libImaging/Jpeg2KDecode.c b/src/libImaging/Jpeg2KDecode.c index 8cce545..60d4d77 100644 --- a/src/libImaging/Jpeg2KDecode.c +++ b/src/libImaging/Jpeg2KDecode.c @@ -589,7 +589,7 @@ j2k_decode_entry(Imaging im, ImagingCodecState state) j2k_unpacker_t unpack = NULL; size_t buffer_size = 0, tile_bytes = 0; unsigned n, tile_height, tile_width; - int components; + int total_component_width = 0; stream = opj_stream_create(BUFFER_SIZE, OPJ_TRUE); @@ -753,23 +753,40 @@ j2k_decode_entry(Imaging im, ImagingCodecState state) goto quick_exit; } + if (tile_info.nb_comps != image->numcomps) { + state->errcode = IMAGING_CODEC_BROKEN; + state->state = J2K_STATE_FAILED; + goto quick_exit; + } + /* Sometimes the tile_info.datasize we get back from openjpeg - is less than numcomps*w*h, and we overflow in the + is less than sum(comp_bytes)*w*h, and we overflow in the shuffle stage */ tile_width = tile_info.x1 - tile_info.x0; tile_height = tile_info.y1 - tile_info.y0; - components = tile_info.nb_comps == 3 ? 4 : tile_info.nb_comps; - if (( tile_width > UINT_MAX / components ) || - ( tile_height > UINT_MAX / components ) || - ( tile_width > UINT_MAX / (tile_height * components )) || - ( tile_height > UINT_MAX / (tile_width * components ))) { + + /* Total component width = sum (component_width) e.g, it's + legal for an la file to have a 1 byte width for l, and 4 for + a. and then a malicious file could have a smaller tile_bytes + */ + + for (n=0; n < tile_info.nb_comps; n++) { + // see csize /acsize calcs + int csize = (image->comps[n].prec + 7) >> 3; + csize = (csize == 3) ? 4 : csize; + total_component_width += csize; + } + if ((tile_width > UINT_MAX / total_component_width) || + (tile_height > UINT_MAX / total_component_width) || + (tile_width > UINT_MAX / (tile_height * total_component_width)) || + (tile_height > UINT_MAX / (tile_width * total_component_width))) { state->errcode = IMAGING_CODEC_BROKEN; state->state = J2K_STATE_FAILED; goto quick_exit; } - tile_bytes = tile_width * tile_height * components; + tile_bytes = tile_width * tile_height * total_component_width; if (tile_bytes > tile_info.data_size) { tile_info.data_size = tile_bytes; -- 2.23.0