gnu: file: Fix CVE-2017-1000249.

* gnu/packages/file.scm (file)[replacement]: New field.
(file/fixed): New variable.
* gnu/packages/commencement.scm (file-boot0): Use package/inherit.
* gnu/packages/patches/file-CVE-2017-1000249.patch.
* gnu/local.mk (dist_patch_DATA): Register it.

gnu/local.mk

@@ -603,6 +603,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/fasthenry-spFactor.patch			\
   %D%/packages/patches/fcgi-2.4.0-gcc44-fixes.patch		\
   %D%/packages/patches/fcgi-2.4.0-poll.patch			\
+  %D%/packages/patches/file-CVE-2017-1000249.patch		\
   %D%/packages/patches/findutils-localstatedir.patch		\
   %D%/packages/patches/findutils-gnulib-multi-core.patch	\
   %D%/packages/patches/findutils-test-xargs.patch		\

gnu/packages/commencement.scm

@@ -112,8 +112,7 @@
 
 (define file-boot0
   (package-with-bootstrap-guile
-   (package-with-explicit-inputs (package
+   (package-with-explicit-inputs (package/inherit file
-                                   (inherit file)
                                    (name "file-boot0"))
                                  `(("make" ,gnu-make-boot0)
                                    ,@%bootstrap-inputs)

gnu/packages/file.scm

@@ -1,7 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2013 Andreas Enge <andreas@enge.fr>
 ;;; Copyright © 2014, 2015 Mark H Weaver <mhw@netris.org>
-;;; Copyright © 2016 Efraim Flashner <efraim@flashner.co.il>
+;;; Copyright © 2016, 2017 Efraim Flashner <efraim@flashner.co.il>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -27,7 +27,8 @@
 
 (define-public file
   (package
-   (name "file")
+    (replacement file/fixed)
+    (name "file")
     (version "5.30")
     (source (origin
               (method url-fetch)
@@ -51,3 +52,9 @@ of the file.")
    (license bsd-2)
    (home-page "http://www.darwinsys.com/file/")))
 
+(define file/fixed
+  (package
+    (inherit file)
+    (source (origin
+              (inherit (package-source file))
+              (patches (search-patches "file-CVE-2017-1000249.patch"))))))

gnu/packages/patches/file-CVE-2017-1000249.patch

@@ -0,0 +1,27 @@
+https://github.com/file/file/commit/35c94dc6acc418f1ad7f6241a6680e5327495793.patch
+http://openwall.com/lists/oss-security/2017/09/05/3
+
+The patch is minorly modified to apply to file-5.30
+
+From 35c94dc6acc418f1ad7f6241a6680e5327495793 Mon Sep 17 00:00:00 2001
+From: Christos Zoulas <christos@zoulas.com>
+Date: Sun, 27 Aug 2017 07:55:02 +0000
+Subject: [PATCH] Fix always true condition (Thomas Jarosch)
+
+---
+ src/readelf.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/readelf.c b/src/readelf.c
+index 81451827..5f425c97 100644
+--- a/src/readelf.c
++++ b/src/readelf.c
+@@ -511,7 +511,7 @@ do_bid_note(struct magic_set *ms, unsigned char *nbuf, uint32_t type,
+     size_t noff, size_t doff, int *flags)
+ {
+ 	if (namesz == 4 && strcmp((char *)&nbuf[noff], "GNU") == 0 &&
+-	    type == NT_GNU_BUILD_ID && (descsz >= 4 || descsz <= 20)) {
++	    type == NT_GNU_BUILD_ID && (descsz >= 4 && descsz <= 20)) {
+ 		uint8_t desc[20];
+ 		const char *btype;
+ 		uint32_t i;