[FFmpeg-devel] [PATCH] avformat/cache: Use int64_t to avoid int overflow in cache_read

Bryan Huh bryan at box.com
Mon Nov 2 19:20:39 CET 2015

Fixes an issue where an int64_t ffurl_seek return-value was being stored
in an int (32-bit) "r" variable, leading to integer overflow when seeking
into a large file (>2GB), and ultimately a "Failed to perform internal
seek" error mesage.

To test, try running `ffprobe 'cache:http://<something>'` on a file that
is ~3GB large, whose moov atom is at the end of the file
 libavformat/cache.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/libavformat/cache.c b/libavformat/cache.c
index a762aa9..31f63e6 100644
--- a/libavformat/cache.c
+++ b/libavformat/cache.c
@@ -156,7 +156,7 @@ static int cache_read(URLContext *h, unsigned char *buf, int size)
     Context *c= h->priv_data;
     CacheEntry *entry, *next[2] = {NULL, NULL};
-    int r;
+    int64_t r;
     entry = av_tree_find(c->root, &c->logical_pos, cmp, (void**)next);

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