[FFmpeg-devel] [PATCH 5/5] avformat/jpegxl_anim_dec: avoid overrun with jxlp boxes in container

[Leo Izen]

This should avoid overrunning buffers with jxlp boxes if the size is
zero or if the size is so small the box is invalid.

Signed-off-by: Leo Izen <leo.izen at gmail.com>
---
 libavformat/jpegxl_anim_dec.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/libavformat/jpegxl_anim_dec.c b/libavformat/jpegxl_anim_dec.c
index 6ea6c46d8f..c9e4dcd5fc 100644
--- a/libavformat/jpegxl_anim_dec.c
+++ b/libavformat/jpegxl_anim_dec.c
@@ -76,8 +76,14 @@ static int jpegxl_collect_codestream_header(const uint8_t *input_buffer, int inp
         tag = AV_RL32(b);
         b += 4;
         if (tag == MKTAG('j', 'x', 'l', 'p')) {
+            if (b - input_buffer >= input_len - 4)
+                break;
             b += 4;
-            size -= 4;
+            if (size) {
+                if (size < 4)
+                    return AVERROR_INVALIDDATA;
+                size -= 4;
+            }
         }
 
         if (tag == MKTAG('j', 'x', 'l', 'c') || tag == MKTAG('j', 'x', 'l', 'p')) {
-- 
2.40.1