Sign Up
Log In
Log In
or
Sign Up
Places
All Projects
Status Monitor
Collapse sidebar
SUSE:SLE-12-SP4:Update
gstreamer-plugins-good.25486
gstreamer-plugins-good-CVE-2021-3497.patch
Overview
Repositories
Revisions
Requests
Users
Attributes
Meta
File gstreamer-plugins-good-CVE-2021-3497.patch of Package gstreamer-plugins-good.25486
From a9c2f1fc2c3d1b0152fc44d62a70100a04f775ed Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= <sebastian@centricular.com> Date: Thu, 4 Mar 2021 13:05:19 +0200 Subject: [PATCH] matroskademux: Fix extraction of multichannel WavPack The old code had a couple of issues that all lead to potential memory safety bugs. - Use a constant for the Wavpack4Header size instead of using sizeof. It's written out into the data and not from the struct and who knows what special alignment/padding requirements some C compilers have. - gst_buffer_set_size() does not realloc the buffer when setting a bigger size than allocated, it only allows growing up to the maximum allocated size. Instead use a GstAdapter to collect all the blocks and take out everything at once in the end. - Check that enough data is actually available in the input and otherwise handle it an error in all cases instead of silently ignoring it. Among other things this fixes out of bounds writes because the code assumed gst_buffer_set_size() can grow the buffer and simply wrote after the end of the buffer. Thanks to Natalie Silvanovich for reporting. Fixes https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/issues/859 Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/905> --- gst/matroska/matroska-demux.c | 99 +++++++++++++++++++---------------- gst/matroska/matroska-ids.h | 2 + 2 files changed, 55 insertions(+), 46 deletions(-) diff --git a/gst/matroska/matroska-demux.c b/gst/matroska/matroska-demux.c index a1704f9fa..3117ee654 100644 --- a/gst/matroska/matroska-demux.c +++ b/gst/matroska/matroska-demux.c @@ -3262,6 +3262,12 @@ gst_matroska_demux_add_wvpk_header (GstElement * element, guint32 block_samples, tmp; gsize size = gst_buffer_get_size (*buf); + if (size < 4) { + GST_ERROR_OBJECT (element, "Too small wavpack buffer"); + gst_buffer_unmap (*buf, &map); + return GST_FLOW_ERROR; + } + gst_buffer_extract (*buf, 0, &tmp, sizeof (guint32)); block_samples = GUINT32_FROM_LE (tmp); /* we need to reconstruct the header of the wavpack block */ @@ -3269,10 +3275,10 @@ gst_matroska_demux_add_wvpk_header (GstElement * element, /* -20 because ck_size is the size of the wavpack block -8 * and lace_size is the size of the wavpack block + 12 * (the three guint32 of the header that already are in the buffer) */ - wvh.ck_size = size + sizeof (Wavpack4Header) - 20; + wvh.ck_size = size + WAVPACK4_HEADER_SIZE - 20; /* block_samples, flags and crc are already in the buffer */ - newbuf = gst_buffer_new_allocate (NULL, sizeof (Wavpack4Header) - 12, NULL); + newbuf = gst_buffer_new_allocate (NULL, WAVPACK4_HEADER_SIZE - 12, NULL); gst_buffer_map (newbuf, &outmap, GST_MAP_WRITE); data = outmap.data; @@ -3297,9 +3303,11 @@ gst_matroska_demux_add_wvpk_header (GstElement * element, audiocontext->wvpk_block_index += block_samples; } else { guint8 *outdata = NULL; - guint outpos = 0; - gsize buf_size, size, out_size = 0; + gsize buf_size, size; guint32 block_samples, flags, crc, blocksize; + GstAdapter *adapter; + + adapter = gst_adapter_new (); gst_buffer_map (*buf, &map, GST_MAP_READ); buf_data = map.data; @@ -3308,6 +3316,7 @@ gst_matroska_demux_add_wvpk_header (GstElement * element, if (buf_size < 4) { GST_ERROR_OBJECT (element, "Too small wavpack buffer"); gst_buffer_unmap (*buf, &map); + g_object_unref (adapter); return GST_FLOW_ERROR; } @@ -3329,59 +3338,57 @@ gst_matroska_demux_add_wvpk_header (GstElement * element, data += 4; size -= 4; - if (blocksize == 0 || size < blocksize) - break; - - g_assert ((newbuf == NULL) == (outdata == NULL)); + if (blocksize == 0 || size < blocksize) { + GST_ERROR_OBJECT (element, "Too small wavpack buffer"); + gst_buffer_unmap (*buf, &map); + g_object_unref (adapter); + return GST_FLOW_ERROR; + } - if (newbuf == NULL) { - out_size = sizeof (Wavpack4Header) + blocksize; - newbuf = gst_buffer_new_allocate (NULL, out_size, NULL); + g_assert (newbuf == NULL); - gst_buffer_copy_into (newbuf, *buf, - GST_BUFFER_COPY_TIMESTAMPS | GST_BUFFER_COPY_FLAGS, 0, -1); + newbuf = + gst_buffer_new_allocate (NULL, WAVPACK4_HEADER_SIZE + blocksize, + NULL); + gst_buffer_map (newbuf, &outmap, GST_MAP_WRITE); + outdata = outmap.data; + + outdata[0] = 'w'; + outdata[1] = 'v'; + outdata[2] = 'p'; + outdata[3] = 'k'; + outdata += 4; + + GST_WRITE_UINT32_LE (outdata, blocksize + WAVPACK4_HEADER_SIZE - 8); + GST_WRITE_UINT16_LE (outdata + 4, wvh.version); + GST_WRITE_UINT8 (outdata + 6, wvh.track_no); + GST_WRITE_UINT8 (outdata + 7, wvh.index_no); + GST_WRITE_UINT32_LE (outdata + 8, wvh.total_samples); + GST_WRITE_UINT32_LE (outdata + 12, wvh.block_index); + GST_WRITE_UINT32_LE (outdata + 16, block_samples); + GST_WRITE_UINT32_LE (outdata + 20, flags); + GST_WRITE_UINT32_LE (outdata + 24, crc); + outdata += 28; + + memcpy (outdata, data, blocksize); - outpos = 0; - gst_buffer_map (newbuf, &outmap, GST_MAP_WRITE); - outdata = outmap.data; - } else { - gst_buffer_unmap (newbuf, &outmap); - out_size += sizeof (Wavpack4Header) + blocksize; - gst_buffer_set_size (newbuf, out_size); - gst_buffer_map (newbuf, &outmap, GST_MAP_WRITE); - outdata = outmap.data; - } + gst_buffer_unmap (newbuf, &outmap); + gst_adapter_push (adapter, newbuf); + newbuf = NULL; - outdata[outpos] = 'w'; - outdata[outpos + 1] = 'v'; - outdata[outpos + 2] = 'p'; - outdata[outpos + 3] = 'k'; - outpos += 4; - - GST_WRITE_UINT32_LE (outdata + outpos, - blocksize + sizeof (Wavpack4Header) - 8); - GST_WRITE_UINT16_LE (outdata + outpos + 4, wvh.version); - GST_WRITE_UINT8 (outdata + outpos + 6, wvh.track_no); - GST_WRITE_UINT8 (outdata + outpos + 7, wvh.index_no); - GST_WRITE_UINT32_LE (outdata + outpos + 8, wvh.total_samples); - GST_WRITE_UINT32_LE (outdata + outpos + 12, wvh.block_index); - GST_WRITE_UINT32_LE (outdata + outpos + 16, block_samples); - GST_WRITE_UINT32_LE (outdata + outpos + 20, flags); - GST_WRITE_UINT32_LE (outdata + outpos + 24, crc); - outpos += 28; - - memmove (outdata + outpos, data, blocksize); - outpos += blocksize; data += blocksize; size -= blocksize; } gst_buffer_unmap (*buf, &map); - gst_buffer_unref (*buf); - if (newbuf) - gst_buffer_unmap (newbuf, &outmap); + newbuf = gst_adapter_take_buffer (adapter, gst_adapter_available (adapter)); + g_object_unref (adapter); + gst_buffer_copy_into (newbuf, *buf, + GST_BUFFER_COPY_TIMESTAMPS | GST_BUFFER_COPY_FLAGS, 0, -1); + gst_buffer_unref (*buf); *buf = newbuf; + audiocontext->wvpk_block_index += block_samples; } diff --git a/gst/matroska/matroska-ids.h b/gst/matroska/matroska-ids.h index c2e41e549..48fd54066 100644 --- a/gst/matroska/matroska-ids.h +++ b/gst/matroska/matroska-ids.h @@ -648,6 +648,8 @@ typedef struct _Wavpack4Header { guint32 crc; /* crc for actual decoded data */ } Wavpack4Header; +#define WAVPACK4_HEADER_SIZE (32) + typedef enum { GST_MATROSKA_TRACK_ENCODING_SCOPE_FRAME = (1<<0), GST_MATROSKA_TRACK_ENCODING_SCOPE_CODEC_DATA = (1<<1), -- 2.32.0
Locations
Projects
Search
Status Monitor
Help
OpenBuildService.org
Documentation
API Documentation
Code of Conduct
Contact
Support
@OBShq
Terms
openSUSE Build Service is sponsored by
The Open Build Service is an
openSUSE project
.
Sign Up
Log In
Places
Places
All Projects
Status Monitor
