blob: be01eabd5bccbb9441d681a4d9e2ef0c88de932d (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
From 7402d19bc155f74b39a19d5478375dbfe95a76c6 Mon Sep 17 00:00:00 2001
From: Natanael Copa <ncopa@alpinelinux.org>
Date: Wed, 3 Aug 2016 13:23:57 +0200
Subject: [PATCH 12/15] gzip: fix compression level bug. Closes 9131
fix broken logic to get the gzip_level_config value from options -1 to
-9.
This fixes an off-by-one bug that caused gzip -9 output bigger files
than the other compression levels.
It fixes so that compression level 1 to 3 are actually mapped to level 4
as comments say.
It also fixes that levels -4 to -9 is mapped to correct level and avoids
out-of-bounds access.
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
---
archival/gzip.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/archival/gzip.c b/archival/gzip.c
index 8f1e4ff..15ba57c 100644
--- a/archival/gzip.c
+++ b/archival/gzip.c
@@ -2220,10 +2220,7 @@ int gzip_main(int argc UNUSED_PARAM, char **argv)
opt >>= ENABLE_GUNZIP ? 7 : 5; /* drop cfv[dt]qn bits */
if (opt == 0)
opt = 1 << 6; /* default: 6 */
- /* Map 1..3 to 4 */
- if (opt & 0x7)
- opt |= 1 << 4;
- opt = ffs(opt >> 3);
+ opt = ffs(opt >> 4); /* Maps 1..3 to 4 */
max_chain_length = 1 << gzip_level_config[opt].chain_shift;
good_match = gzip_level_config[opt].good;
max_lazy_match = gzip_level_config[opt].lazy2 * 2;
--
2.9.1
|
