Same issue as #72926 in another place.

smalyshev · smalyshev · commit b578580e888b · 2016-09-04T20:49:34.000-07:00
diff --git a/ext/exif/exif.c b/ext/exif/exif.c
@@ -3734,8 +3734,11 @@ static int exif_process_IFD_in_TIFF(image_info_type *ImageInfo, size_t dir_offse
 									fgot = php_stream_read(ImageInfo->infile, ImageInfo->Thumbnail.data, ImageInfo->Thumbnail.size);
 									if (fgot < ImageInfo->Thumbnail.size) {
 										EXIF_ERRLOG_THUMBEOF(ImageInfo)
+										efree(ImageInfo->Thumbnail.data);
+										ImageInfo->Thumbnail.data = NULL;
+									} else {
+										exif_thumbnail_build(ImageInfo TSRMLS_CC);
 									}
-									exif_thumbnail_build(ImageInfo TSRMLS_CC);
 								}
 							}
 						}

Original file line number	Diff line number	Diff line change
`@@ -3734,8 +3734,11 @@ static int exif_process_IFD_in_TIFF(image_info_type *ImageInfo, size_t dir_offse`
`3734`	`3734`	`fgot = php_stream_read(ImageInfo->infile, ImageInfo->Thumbnail.data, ImageInfo->Thumbnail.size);`
`3735`	`3735`	`if (fgot < ImageInfo->Thumbnail.size) {`
`3736`	`3736`	`EXIF_ERRLOG_THUMBEOF(ImageInfo)`
	`3737`	`+ efree(ImageInfo->Thumbnail.data);`
	`3738`	`+ ImageInfo->Thumbnail.data = NULL;`
	`3739`	`+ } else {`
	`3740`	`+ exif_thumbnail_build(ImageInfo TSRMLS_CC);`
`3737`	`3741`	`}`
`3738`		`- exif_thumbnail_build(ImageInfo TSRMLS_CC);`
`3739`	`3742`	`}`
`3740`	`3743`	`}`
`3741`	`3744`	`}`