01/31: gnu: flex-2.6.1: Build fix for the Hurd.

[guix-commits]

janneke pushed a commit to branch wip-hurd
in repository guix.

commit 827a6afb0ebb807644512e3b6bd6777e69bde996
Author: Jan Nieuwenhuizen <address@hidden>
AuthorDate: Sun Mar 8 22:59:45 2020 +0100

    gnu: flex-2.6.1: Build fix for the Hurd.
    
    * gnu/packages/patches/flex-2.6.1-hurd-path-max.patch: New file.
    * gnu/local.mk (dist_patch_DATA): Add it.
    * gnu/packages/flex.scm (flex-2.6.1): Use it.
---
 gnu/local.mk                                       |   1 +
 gnu/packages/flex.scm                              |   2 +
 .../patches/flex-2.6.1-hurd-path-max.patch         | 140 +++++++++++++++++++++
 3 files changed, 143 insertions(+)

diff --git a/gnu/local.mk b/gnu/local.mk
index 21a149c..b9a06c9 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -875,6 +875,7 @@ dist_patch_DATA =                                           
\
   %D%/packages/patches/findutils-localstatedir.patch           \
   %D%/packages/patches/findutils-test-rwlock-threads.patch     \
   %D%/packages/patches/flann-cmake-3.11.patch                  \
+  %D%/packages/patches/flex-2.6.1-hurd-path-max.patch          \
   %D%/packages/patches/flint-ldconfig.patch                    \
   %D%/packages/patches/foomatic-filters-CVE-2015-8327.patch    \
   %D%/packages/patches/foomatic-filters-CVE-2015-8560.patch    \
diff --git a/gnu/packages/flex.scm b/gnu/packages/flex.scm
index f9a2120..b6e4521 100644
--- a/gnu/packages/flex.scm
+++ b/gnu/packages/flex.scm
@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2012, 2013, 2014, 2019 Ludovic Courtès <address@hidden>
 ;;; Copyright © 2016 Efraim Flashner <address@hidden>
+;;; Copyright © 2020 Jan (janneke) Nieuwenhuizen <address@hidden>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -84,6 +85,7 @@ executes the corresponding C code.")
               (uri (string-append "https://github.com/westes/flex";
                                   "/releases/download/v" version "/"
                                   "flex-" version ".tar.xz"))
+              (patches (search-patches "flex-2.6.1-hurd-path-max.patch"))
              (sha256
               (base32
                "0gqhk4vkwy4gl9xbpgkljph8c0a5kpijz6wd0p5r9q202qn42yic"))))))
diff --git a/gnu/packages/patches/flex-2.6.1-hurd-path-max.patch 
b/gnu/packages/patches/flex-2.6.1-hurd-path-max.patch
new file mode 100644
index 0000000..60c18f7
--- /dev/null
+++ b/gnu/packages/patches/flex-2.6.1-hurd-path-max.patch
@@ -0,0 +1,140 @@
+This patch is needed to build flex-2.6.1 on the Hurd.
+
+It is a backport of three upstream commits
+
+    
https://github.com/westes/flex/commit/9160ceb67ff5317753ff71c623b037126862a32f
+    
https://github.com/westes/flex/commit/babe9a1e8eeb5497756d4d7998dd1ca82c62a189
+    
https://github.com/westes/flex/commit/7975c43384d766ca12cb3f292754dbdc34168886
+
+From 7c960b48c99b2044b65c0bc2af9e57202e326a90 Mon Sep 17 00:00:00 2001
+From: rlar <rlar>
+Date: Sun, 28 Feb 2016 21:12:45 +0100
+Subject: [PATCH 1/3] cast to get rid of warnings
+
+---
+ src/main.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/main.c b/src/main.c
+index e329e4e..1288a5d 100644
+--- a/src/main.c
++++ b/src/main.c
+@@ -360,14 +360,14 @@ void check_options (void)
+                       } else {
+                               do {
+                                       char m4_path[PATH_MAX];
+-                                      int length = strlen(path);
++                                      size_t length = strlen(path);
+                                       struct stat sbuf;
+ 
+                                       const char *endOfDir = strchr(path, 
':');
+                                       if (!endOfDir)
+                                               endOfDir = path+length;
+ 
+-                                      if ((endOfDir-path+2) >= 
sizeof(m4_path)) {
++                                      if (endOfDir + 2 >= path + 
sizeof(m4_path)) {
+                                           path = endOfDir+1;
+                                               continue;
+                                       }
+-- 
+2.24.0
+
+From c85ca046b4d3171bdbb26e73f0ee4eb0b0921daa Mon Sep 17 00:00:00 2001
+From: Tobias Klauser <address@hidden>
+Date: Thu, 31 Mar 2016 10:09:57 +0200
+Subject: [PATCH 2/3] Fix potential buffer overflow in strncat()
+
+When using clang/llvm 3.8 to compile flex, the following warning is
+emitted:
+
+main.c:378:27: warning: the value of the size argument in 'strncat' is too 
large, might lead to a buffer overflow [-Wstrncat-size]
+                                        strncat(m4_path, m4, sizeof(m4_path));
+                                                             ^~~~~~~~~~~~~~~
+main.c:378:27: note: change the argument to be the free space in the 
destination buffer minus the terminating null byte
+                                        strncat(m4_path, m4, sizeof(m4_path));
+                                                             ^~~~~~~~~~~~~~~
+                                                             sizeof(m4_path) - 
strlen(m4_path) - 1
+
+Fix it up by using the solution proposed by the warning message.
+---
+ src/main.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/main.c b/src/main.c
+index 1288a5d..b4d47cb 100644
+--- a/src/main.c
++++ b/src/main.c
+@@ -375,7 +375,7 @@ void check_options (void)
+                                       strncpy(m4_path, path, sizeof(m4_path));
+                                       m4_path[endOfDir-path] = '/';
+                                       m4_path[endOfDir-path+1] = '\0';
+-                                      strncat(m4_path, m4, sizeof(m4_path));
++                                      strncat(m4_path, m4, sizeof(m4_path) - 
strlen(m4_path) - 1);
+                                       if (stat(m4_path, &sbuf) == 0 &&
+                                               (S_ISREG(sbuf.st_mode)) && 
sbuf.st_mode & S_IXUSR) {
+                                               m4 = strdup(m4_path);
+-- 
+2.24.0
+
+From 376c31df7d7dcbd7ca0616d49f32086ca17a18d3 Mon Sep 17 00:00:00 2001
+From: Samuel Thibault <address@hidden>
+Date: Thu, 29 Dec 2016 08:44:22 -0500
+Subject: [PATCH 3/3] scanner: allocate correct buffer size for m4 path.
+
+Flex did not check the length of the m4 path which could lead to a
+buffer overflow in some cases. Additionally, not all platforms believe
+in PATH_MAX, so stop relying on it.
+
+Fixes #138
+---
+ src/main.c | 26 ++++++++++++--------------
+ 1 file changed, 12 insertions(+), 14 deletions(-)
+
+diff --git a/src/main.c b/src/main.c
+index b4d47cb..7ae7980 100644
+--- a/src/main.c
++++ b/src/main.c
+@@ -358,8 +358,8 @@ void check_options (void)
+                       if (!path) {
+                               m4 = M4;
+                       } else {
++                              int m4_length = strlen(m4);
+                               do {
+-                                      char m4_path[PATH_MAX];
+                                       size_t length = strlen(path);
+                                       struct stat sbuf;
+ 
+@@ -367,19 +367,17 @@ void check_options (void)
+                                       if (!endOfDir)
+                                               endOfDir = path+length;
+ 
+-                                      if (endOfDir + 2 >= path + 
sizeof(m4_path)) {
+-                                          path = endOfDir+1;
+-                                              continue;
+-                                      }
+-
+-                                      strncpy(m4_path, path, sizeof(m4_path));
+-                                      m4_path[endOfDir-path] = '/';
+-                                      m4_path[endOfDir-path+1] = '\0';
+-                                      strncat(m4_path, m4, sizeof(m4_path) - 
strlen(m4_path) - 1);
+-                                      if (stat(m4_path, &sbuf) == 0 &&
+-                                              (S_ISREG(sbuf.st_mode)) && 
sbuf.st_mode & S_IXUSR) {
+-                                              m4 = strdup(m4_path);
+-                                              break;
++                                      {
++                                              char m4_path[endOfDir-path + 1 
+ m4_length + 1];
++
++                                              memcpy(m4_path, path, 
endOfDir-path);
++                                              m4_path[endOfDir-path] = '/';
++                                              memcpy(m4_path + 
(endOfDir-path) + 1, m4, m4_length + 1);
++                                              if (stat(m4_path, &sbuf) == 0 &&
++                                                      (S_ISREG(sbuf.st_mode)) 
&& sbuf.st_mode & S_IXUSR) {
++                                                      m4 = strdup(m4_path);
++                                                      break;
++                                              }
+                                       }
+                                       path = endOfDir+1;
+                               } while (path[0]);
+-- 
+2.24.0
+