nixpkgs/pkgs/development/libraries/zlib/CVE-2016-9842.patch

30 lines
1.0 KiB
Diff

From e54e1299404101a5a9d0cf5e45512b543967f958 Mon Sep 17 00:00:00 2001
From: Mark Adler <madler@alumni.caltech.edu>
Date: Sat, 5 Sep 2015 17:45:55 -0700
Subject: [PATCH] Avoid shifts of negative values inflateMark().
The C standard says that bit shifts of negative integers is
undefined. This casts to unsigned values to assure a known
result.
---
inflate.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/inflate.c b/inflate.c
index 2889e3a..a718416 100644
--- a/inflate.c
+++ b/inflate.c
@@ -1506,9 +1506,10 @@ z_streamp strm;
{
struct inflate_state FAR *state;
- if (strm == Z_NULL || strm->state == Z_NULL) return -1L << 16;
+ if (strm == Z_NULL || strm->state == Z_NULL)
+ return (long)(((unsigned long)0 - 1) << 16);
state = (struct inflate_state FAR *)strm->state;
- return ((long)(state->back) << 16) +
+ return (long)(((unsigned long)((long)state->back)) << 16) +
(state->mode == COPY ? state->length :
(state->mode == MATCH ? state->was - state->length : 0));
}