From e54e1299404101a5a9d0cf5e45512b543967f958 Mon Sep 17 00:00:00 2001 From: Mark Adler 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. CVE: CVE-2016-9842 Upstream-Status: Backport Signed-off-by: Anuj Mittal --- inflate.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/zlib/inflate.c b/zlib/inflate.c index 2889e3a0..a7184167 100644 --- a/zlib/inflate.c +++ b/zlib/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)); }