Incomplete crypted files would lead to a read after buffer boundary
otherwise.

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: [email protected]
---

This version should work better in the case we the patial packet
isn't caused by an end of file.

 libavformat/omadec.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/libavformat/omadec.c b/libavformat/omadec.c
index b05a7d5..87d2576 100644
--- a/libavformat/omadec.c
+++ b/libavformat/omadec.c
@@ -402,6 +402,9 @@ static int oma_read_packet(AVFormatContext *s, AVPacket 
*pkt)
     int packet_size = s->streams[0]->codec->block_align;
     int ret = av_get_packet(s->pb, pkt, packet_size);

+    if (ret < packet_size)
+        pkt->flags |= AV_PKT_FLAG_CORRUPT;
+
     if (ret <= 0)
         return AVERROR(EIO);

@@ -410,8 +413,11 @@ static int oma_read_packet(AVFormatContext *s, AVPacket 
*pkt)
     if (oc->encrypted) {
         /* previous unencrypted block saved in IV for
          * the next packet (CBC mode) */
-        av_des_crypt(&oc->av_des, pkt->data, pkt->data,
-                     (packet_size >> 3), oc->iv, 1);
+        if (ret == packet_size)
+            av_des_crypt(&oc->av_des, pkt->data, pkt->data,
+                         (packet_size >> 3), oc->iv, 1);
+        else
+            memset(oc->iv, 0, 8);
     }

     return ret;
--
1.8.1.5

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