From d354ffc9e0d1920dfc54cf13f1fc5d89405ee3f1 Mon Sep 17 00:00:00 2001
From: OpenWrt community <openwrt-devel@lists.openwrt.org>
Date: Mon, 30 Oct 2023 14:49:12 +0100
Subject: [PATCH] fix: infinite loop because of an empty bzip2 data

https://nvd.nist.gov/vuln/detail/CVE-2015-7697

CVE: CVE-2015-7697
---
 extract.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/extract.c b/extract.c
index d816603..ad8b3f7 100644
--- a/extract.c
+++ b/extract.c
@@ -2728,6 +2728,12 @@ __GDEF
     int repeated_buf_err;
     bz_stream bstrm;
 
+    if (G.incnt <= 0 && G.csize <= 0L) {
+        /* avoid an infinite loop */
+        Trace((stderr, "UZbunzip2() got empty input\n"));
+        return 2;
+    }
+
 #if (defined(DLL) && !defined(NO_SLIDE_REDIR))
     if (G.redirect_slide)
         wsize = G.redirect_size, redirSlide = G.redirect_buffer;
--