From e33578a3c2b85a68962003bd053abda9409e73a2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= Date: Thu, 25 Apr 2024 15:21:20 +0300 Subject: [PATCH] exiftag: Prevent integer overflows and out of bounds reads when handling undefined tags Fixes ZDI-CAN-23896 Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/3483 Part-of: CVE: CVE-2024-4453 Upstream-Status: Backport [https://gitlab.freedesktop.org/gstreamer/gstreamer/-/commit/e33578a3c2b85a68] Signed-off-by: Archana Polampalli --- gst-libs/gst/tag/gstexiftag.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/gst-libs/gst/tag/gstexiftag.c b/gst-libs/gst/tag/gstexiftag.c index ed41ccf..3b9a2be 100644 --- a/gst-libs/gst/tag/gstexiftag.c +++ b/gst-libs/gst/tag/gstexiftag.c @@ -1383,6 +1383,7 @@ parse_exif_undefined_tag (GstExifReader * reader, const GstExifTagMatch * tag, if (count > 4) { GstMapInfo info; + gsize alloc_size; if (offset < reader->base_offset) { GST_WARNING ("Offset is smaller (%u) than base offset (%u)", offset, @@ -1404,14 +1405,28 @@ parse_exif_undefined_tag (GstExifReader * reader, const GstExifTagMatch * tag, return; } + if (info.size - real_offset < count) { + GST_WARNING ("Invalid size %u for buffer of size %" G_GSIZE_FORMAT + ", not adding tag %s", count, info.size, tag->gst_tag); + gst_buffer_unmap (reader->buffer, &info); + return; + } + + if (!g_size_checked_add (&alloc_size, count, 1)) { + GST_WARNING ("Invalid size %u for buffer of size %" G_GSIZE_FORMAT + ", not adding tag %s", real_offset, info.size, tag->gst_tag); + gst_buffer_unmap (reader->buffer, &info); + return; + } + /* +1 because it could be a string without the \0 */ - data = malloc (sizeof (guint8) * count + 1); + data = malloc (alloc_size); memcpy (data, info.data + real_offset, count); data[count] = 0; gst_buffer_unmap (reader->buffer, &info); } else { - data = malloc (sizeof (guint8) * count + 1); + data = malloc (count + 1); memcpy (data, (guint8 *) offset_as_data, count); data[count] = 0; } -- 2.40.0