[OE-core] [PATCH 2/3] bash: fix CVE-2014-6271

[Robert Yang]

From: Ross Burton <ross.burton at intel.com>

CVE-2014-6271 aka ShellShock.

"GNU Bash through 4.3 processes trailing strings after function definitions in
the values of environment variables, which allows remote attackers to execute
arbitrary code via a crafted environment."

(From OE-Core master rev: 798d833c9d4bd9ab287fa86b85b4d5f128170ed3)

Signed-off-by: Ross Burton <ross.burton at intel.com>
Signed-off-by: Richard Purdie <richard.purdie at linuxfoundation.org>
Signed-off-by: Robert Yang <liezhi.yang at windriver.com>
---
 .../bash/bash-3.2.48/cve-2014-6271.patch           |   77 ++++++++++++++++++++
 meta/recipes-extended/bash/bash_3.2.48.bb          |    1 +
 2 files changed, 78 insertions(+)
 create mode 100644 meta/recipes-extended/bash/bash-3.2.48/cve-2014-6271.patch

diff --git a/meta/recipes-extended/bash/bash-3.2.48/cve-2014-6271.patch b/meta/recipes-extended/bash/bash-3.2.48/cve-2014-6271.patch
new file mode 100644
index 0000000..7226ffb
--- /dev/null
+++ b/meta/recipes-extended/bash/bash-3.2.48/cve-2014-6271.patch
@@ -0,0 +1,77 @@
+Fix CVE-2014-6271, aka ShellShock.
+
+Upstream-Status: Backport
+Signed-off-by: Ross Burton <ross.burton at intel.com>
+
+*** ../bash-3.2.51/builtins/common.h	2006-03-06 09:38:44.000000000 -0500
+--- builtins/common.h	2014-09-16 19:08:02.000000000 -0400
+***************
+*** 34,37 ****
+--- 34,39 ----
+  
+  /* Flags for describe_command, shared between type.def and command.def */
++ #define SEVAL_FUNCDEF	0x080		/* only allow function definitions */
++ #define SEVAL_ONECMD	0x100		/* only allow a single command */
+  #define CDESC_ALL		0x001	/* type -a */
+  #define CDESC_SHORTDESC		0x002	/* command -V */
+*** ../bash-3.2.51/builtins/evalstring.c	2008-11-15 17:47:04.000000000 -0500
+--- builtins/evalstring.c	2014-09-16 19:08:02.000000000 -0400
+***************
+*** 235,238 ****
+--- 235,246 ----
+  	      struct fd_bitmap *bitmap;
+  
++ 	      if ((flags & SEVAL_FUNCDEF) && command->type != cm_function_def)
++ 		{
++ 		  internal_warning ("%s: ignoring function definition attempt", from_file);
++ 		  should_jump_to_top_level = 0;
++ 		  last_result = last_command_exit_value = EX_BADUSAGE;
++ 		  break;
++ 		}
++ 
+  	      bitmap = new_fd_bitmap (FD_BITMAP_SIZE);
+  	      begin_unwind_frame ("pe_dispose");
+***************
+*** 292,295 ****
+--- 300,306 ----
+  	      dispose_fd_bitmap (bitmap);
+  	      discard_unwind_frame ("pe_dispose");
++ 
++ 	      if (flags & SEVAL_ONECMD)
++ 		break;
+  	    }
+  	}
+*** ../bash-3.2.51/variables.c	2008-11-15 17:15:06.000000000 -0500
+--- variables.c	2014-09-16 19:10:39.000000000 -0400
+***************
+*** 319,328 ****
+  	  strcpy (temp_string + char_index + 1, string);
+  
+! 	  parse_and_execute (temp_string, name, SEVAL_NONINT|SEVAL_NOHIST);
+! 
+! 	  /* Ancient backwards compatibility.  Old versions of bash exported
+! 	     functions like name()=() {...} */
+! 	  if (name[char_index - 1] == ')' && name[char_index - 2] == '(')
+! 	    name[char_index - 2] = '\0';
+  
+  	  if (temp_var = find_function (name))
+--- 319,326 ----
+  	  strcpy (temp_string + char_index + 1, string);
+  
+! 	  /* Don't import function names that are invalid identifiers from the
+! 	     environment. */
+! 	  if (legal_identifier (name))
+! 	    parse_and_execute (temp_string, name, SEVAL_NONINT|SEVAL_NOHIST|SEVAL_FUNCDEF|SEVAL_ONECMD);
+  
+  	  if (temp_var = find_function (name))
+***************
+*** 333,340 ****
+  	  else
+  	    report_error (_("error importing function definition for `%s'"), name);
+- 
+- 	  /* ( */
+- 	  if (name[char_index - 1] == ')' && name[char_index - 2] == '\0')
+- 	    name[char_index - 2] = '(';		/* ) */
+  	}
+  #if defined (ARRAY_VARS)
+--- 331,334 ----
diff --git a/meta/recipes-extended/bash/bash_3.2.48.bb b/meta/recipes-extended/bash/bash_3.2.48.bb
index fe04b28..5849ed0 100644
--- a/meta/recipes-extended/bash/bash_3.2.48.bb
+++ b/meta/recipes-extended/bash/bash_3.2.48.bb
@@ -12,6 +12,7 @@ SRC_URI = "${GNU_MIRROR}/bash/bash-${PV}.tar.gz;name=tarball \
            file://mkbuiltins_have_stringize.patch \
            file://build-tests.patch \
            file://test-output.patch \
+           file://cve-2014-6271.patch;striplevel=0 \
            file://run-ptest \
           "
 
-- 
1.7.9.5