From 1fac18a8fa269343dd43c9a4bca8d89f307fb7a0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= Date: Fri, 27 Sep 2024 15:50:54 +0300 Subject: [PATCH 05/13] qtdemux: Check sizes of stsc/stco/stts before trying to merge entries Thanks to Antonio Morales for finding and reporting the issue. Fixes GHSL-2024-246 Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/3854 Part-of: CVE: CVE-2024-47598 Upstream-Status: Backport [https://gitlab.freedesktop.org/gstreamer/gstreamer/-/commit/1fac18a8fa269343dd43c9a4bca8d89f307fb7a0] Signed-off-by: Peter Marko --- gst/isomp4/qtdemux.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/gst/isomp4/qtdemux.c b/gst/isomp4/qtdemux.c index 4bb24b1b80..d1aa9ee5a0 100644 --- a/gst/isomp4/qtdemux.c +++ b/gst/isomp4/qtdemux.c @@ -9476,6 +9476,21 @@ qtdemux_merge_sample_table (GstQTDemux * qtdemux, QtDemuxStream * stream) return; } + if (gst_byte_reader_get_remaining (&stream->stts) < 8) { + GST_DEBUG_OBJECT (qtdemux, "Too small stts"); + return; + } + + if (stream->stco.size < 8) { + GST_DEBUG_OBJECT (qtdemux, "Too small stco"); + return; + } + + if (stream->n_samples_per_chunk == 0) { + GST_DEBUG_OBJECT (qtdemux, "No samples per chunk"); + return; + } + /* Parse the stts to get the sample duration and number of samples */ gst_byte_reader_skip_unchecked (&stream->stts, 4); stts_duration = gst_byte_reader_get_uint32_be_unchecked (&stream->stts); @@ -9487,6 +9502,13 @@ qtdemux_merge_sample_table (GstQTDemux * qtdemux, QtDemuxStream * stream) GST_DEBUG_OBJECT (qtdemux, "sample_duration %d, num_chunks %u", stts_duration, num_chunks); + if (gst_byte_reader_get_remaining (&stream->stsc) < + stream->n_samples_per_chunk * 3 * 4 + + (stream->n_samples_per_chunk - 1) * 4) { + GST_DEBUG_OBJECT (qtdemux, "Too small stsc"); + return; + } + /* Now parse stsc, convert chunks into single samples and generate a * new stsc, stts and stsz from this information */ gst_byte_writer_init (&stsc); -- 2.30.2