From: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Date: Thu, 6 Aug 2020 05:17:01 +0000 (+1200)
Subject: lzxpress: avoid technically undefined shift
X-Git-Tag: talloc-2.3.2~662
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0c461f3bd589764c496b530f698e313df50667e6;p=thirdparty%2Fsamba.git

lzxpress: avoid technically undefined shift

UBSAN:

  runtime error: left shift of 1 by 31 places cannot be represented in type 'int'

Credit to OSS-fuzz.

REF: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=22283

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Gary Lockyer <gary@catalyst.net.nz>

Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Mon Aug 31 22:31:13 UTC 2020 on sn-devel-184
---

diff --git a/lib/compression/lzxpress.c b/lib/compression/lzxpress.c
index d8326304455..3453dd36f2a 100644
--- a/lib/compression/lzxpress.c
+++ b/lib/compression/lzxpress.c
@@ -180,7 +180,7 @@ ssize_t lzxpress_compress(const uint8_t *uncompressed,
 				}
 			}
 
-			indic |= 1 << (32 - ((indic_bit % 32) + 1));
+			indic |= 1U << (32 - ((indic_bit % 32) + 1));
 
 			if (best_len > 9) {
 				if (nibble_index == 0) {