From 5c572555cf5d80309a07c30cf7a54b2501493720 Mon Sep 17 00:00:00 2001

From: Mark Adler <madler@alumni.caltech.edu>

Date: Sun, 9 Feb 2020 21:39:09 -0800

Subject: [PATCH] Fix bug in UZinflate() that incorrectly updated G.incnt.

The update assumed a full buffer, which is not always full. This

could result in a false overlapped element detection when a small

deflate-compressed file was unzipped using an old zlib. This

commit remedies that.

---

 inflate.c | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/inflate.c b/inflate.c

index 2f5a015..70e3cc0 100644

--- a/inflate.c

+++ b/inflate.c

@@ -700,7 +700,7 @@ int UZinflate(__G__ is_defl64)

       G.dstrm.total_out));

     G.inptr = (uch *)G.dstrm.next_in;

-    G.incnt = (G.inbuf + INBUFSIZ) - G.inptr;  /* reset for other routines */

+    G.incnt -= G.inptr - G.inbuf;       /* reset for other routines */

 uzinflate_cleanup_exit:

     err = inflateReset(&G.dstrm);