http://sourceware.org/ml/gdb-patches/2014-08/msg00364.html

Subject: [patch+7.8?] Fix crash on Python frame filters with unreadable arg

--d6Gm4EdcadzBjdND

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Hi,

https://bugzilla.redhat.com/show_bug.cgi?id=1126177

ERROR: AddressSanitizer: SEGV on unknown address 0x000000000050 (pc 0x000000992bef sp 0x7ffff9039530 bp 0x7ffff9039540 T0)

    #0 0x992bee in value_type .../gdb/value.c:925

    #1 0x87c951 in py_print_single_arg python/py-framefilter.c:445

    #2 0x87cfae in enumerate_args python/py-framefilter.c:596

    #3 0x87e0b0 in py_print_args python/py-framefilter.c:968

It crashes because frame_arg::val is documented it may contain NULL

(frame_arg::error is then non-NULL) but the code does not handle it.

Another bug is that py_print_single_arg() calls goto out of its TRY_CATCH

which messes up GDB cleanup chain crashing GDB later.

I tried to somehow separate it to two patches first but it in the end kept

them merged.

No regressions on {x86_64,x86_64-m32,i686}-fedorarawhide-linux-gnu.

It is probably 7.7 regression (I have not verified it) due to the introduction

of Python frame filters.

I am not sure if it is more suitable for gdb.arch/ or gdb.python/ , used the

latter.

Thanks,

Jan

--d6Gm4EdcadzBjdND

Content-Type: text/plain; charset=us-ascii

Content-Disposition: inline; filename="pyinvalidarg.patch"

gdb/

2014-08-19  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* python/py-framefilter.c (py_print_single_arg): Handle NULL FA->VAL.

	Fix goto out of TRY_CATCH.

gdb/testsuite/

2014-08-19  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.python/amd64-py-framefilter-invalidarg.S: New file.

	* gdb.python/py-framefilter-invalidarg-gdb.py.in: New file.

	* gdb.python/py-framefilter-invalidarg.exp: New file.

	* gdb.python/py-framefilter-invalidarg.py: New file.

diff --git a/gdb/python/py-framefilter.c b/gdb/python/py-framefilter.c

index 9db83c7..d53282f 100644

--- a/gdb/python/py-framefilter.c

+++ b/gdb/python/py-framefilter.c

@@ -365,9 +365,12 @@ py_print_single_arg (struct ui_out *out,

 {

   struct value *val;

   volatile struct gdb_exception except;

+  enum ext_lang_bt_status retval = EXT_LANG_BT_OK;

   if (fa != NULL)

     {

+      if (fa->val == NULL && fa->error == NULL)

+	return EXT_LANG_BT_OK;

       language = language_def (SYMBOL_LANGUAGE (fa->sym));

       val = fa->val;

     }

@@ -433,16 +436,18 @@ py_print_single_arg (struct ui_out *out,

       /* For MI print the type, but only for simple values.  This seems

 	 weird, but this is how MI choose to format the various output

 	 types.  */

-      if (args_type == MI_PRINT_SIMPLE_VALUES)

+      if (args_type == MI_PRINT_SIMPLE_VALUES && val != NULL)

 	{

 	  if (py_print_type (out, val) == EXT_LANG_BT_ERROR)

 	    {

+	      retval = EXT_LANG_BT_ERROR;

 	      do_cleanups (cleanups);

-	      goto error;

+	      continue;

 	    }

 	}

-      annotate_arg_value (value_type (val));

+      if (val != NULL)

+	annotate_arg_value (value_type (val));

       /* If the output is to the CLI, and the user option "set print

 	 frame-arguments" is set to none, just output "...".  */

@@ -454,27 +459,25 @@ py_print_single_arg (struct ui_out *out,

 	     for the case of MI_PRINT_NO_VALUES.  */

 	  if (args_type != NO_VALUES)

 	    {

-	      if (py_print_value (out, val, opts, 0, args_type, language)

-		  == EXT_LANG_BT_ERROR)

+	      if (val == NULL)

 		{

-		  do_cleanups (cleanups);

-		  goto error;

+		  gdb_assert (fa != NULL && fa->error != NULL);

+		  ui_out_field_fmt (out, "value",

+				    _("<error reading variable: %s>"),

+				    fa->error);

 		}

+	      else if (py_print_value (out, val, opts, 0, args_type, language)

+		       == EXT_LANG_BT_ERROR)

+		retval = EXT_LANG_BT_ERROR;

 	    }

 	}

       do_cleanups (cleanups);

     }

   if (except.reason < 0)

-    {

-      gdbpy_convert_exception (except);

-      goto error;

-    }

-

-  return EXT_LANG_BT_OK;

+    gdbpy_convert_exception (except);

- error:

-  return EXT_LANG_BT_ERROR;

+  return retval;

 }

 /* Helper function to loop over frame arguments provided by the

diff --git a/gdb/testsuite/gdb.python/amd64-py-framefilter-invalidarg.S b/gdb/testsuite/gdb.python/amd64-py-framefilter-invalidarg.S

new file mode 100755

index 0000000..3ac1b23

--- /dev/null

+++ b/gdb/testsuite/gdb.python/amd64-py-framefilter-invalidarg.S

@@ -0,0 +1,261 @@

+/* This testcase is part of GDB, the GNU debugger.

+

+   Copyright 2014 Free Software Foundation, Inc.

+

+   This program is free software; you can redistribute it and/or modify

+   it under the terms of the GNU General Public License as published by

+   the Free Software Foundation; either version 3 of the License, or

+   (at your option) any later version.

+

+   This program is distributed in the hope that it will be useful,

+   but WITHOUT ANY WARRANTY; without even the implied warranty of

+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+   GNU General Public License for more details.

+

+   You should have received a copy of the GNU General Public License

+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

+

+/* This file is compiled from a single line

+   int main (int argc, char **argv) { return 0; }

+   using -g -dA -S -O2 and patched as #if-ed below.  */

+

+	.file	"py-framefilter-invalidarg.c"

+	.text

+.Ltext0:

+	.globl	main

+	.type	main, @function

+main:

+.LFB0:

+	.file 1 "py-framefilter-invalidarg.c"

+	# py-framefilter-invalidarg.c:1

+	.loc 1 1 0

+	.cfi_startproc

+# BLOCK 2 seq:0

+# PRED: ENTRY (FALLTHRU)

+	pushq	%rbp

+	.cfi_def_cfa_offset 16

+	.cfi_offset 6, -16

+	movq	%rsp, %rbp

+	.cfi_def_cfa_register 6

+	movl	%edi, -4(%rbp)

+	movq	%rsi, -16(%rbp)

+	# py-framefilter-invalidarg.c:2

+	.loc 1 2 0

+	movl	$0, %eax

+	# py-framefilter-invalidarg.c:3

+	.loc 1 3 0

+	popq	%rbp

+	.cfi_def_cfa 7, 8

+# SUCC: EXIT [100.0%] 

+	ret

+	.cfi_endproc

+.LFE0:

+	.size	main, .-main

+.Letext0:

+	.section	.debug_info,"",@progbits

+.Ldebug_info0:

+	.long	.Le - .Ls	# Length of Compilation Unit Info

+.Ls:

+	.value	0x4	# DWARF version number

+	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section

+	.byte	0x8	# Pointer Size (in bytes)

+	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)

+	.long	.LASF3	# DW_AT_producer: "GNU C 4.9.1 20140813 (Red Hat 4.9.1-7) -mtune=generic -march=x86-64 -g"

+	.byte	0x1	# DW_AT_language

+	.long	.LASF4	# DW_AT_name: "py-framefilter-invalidarg.c"

+	.long	.LASF5	# DW_AT_comp_dir: ""

+	.quad	.Ltext0	# DW_AT_low_pc

+	.quad	.Letext0-.Ltext0	# DW_AT_high_pc

+	.long	.Ldebug_line0	# DW_AT_stmt_list

+die2d:

+	.uleb128 0x2	# (DIE (0x2d) DW_TAG_subprogram)

+			# DW_AT_external

+	.long	.LASF6	# DW_AT_name: "main"

+	.byte	0x1	# DW_AT_decl_file (py-framefilter-invalidarg.c)

+	.byte	0x1	# DW_AT_decl_line

+			# DW_AT_prototyped

+	.long	die6b-.Ldebug_info0	# DW_AT_type

+	.quad	.LFB0	# DW_AT_low_pc

+	.quad	.LFE0-.LFB0	# DW_AT_high_pc

+	.uleb128 0x1	# DW_AT_frame_base

+	.byte	0x9c	# DW_OP_call_frame_cfa

+			# DW_AT_GNU_all_call_sites

+die4e:

+	.uleb128 0x3	# (DIE (0x4e) DW_TAG_formal_parameter)

+	.long	.LASF0	# DW_AT_name: "argc"

+	.byte	0x1	# DW_AT_decl_file (py-framefilter-invalidarg.c)

+	.byte	0x1	# DW_AT_decl_line

+	.long	die6b-.Ldebug_info0	# DW_AT_type

+#if 0

+	.uleb128 0x2	# DW_AT_location

+	.byte	0x91	# DW_OP_fbreg

+	.sleb128 -20

+#endif

+#if 0

+	.uleb128 1f - 2f	# DW_AT_location

+2:

+	.byte	0x03	# DW_OP_addr

+	.quad 0

+1:

+#endif

+#if 1

+	.uleb128 1f - 2f	# DW_AT_location

+2:

+	.byte	0x13	# DW_OP_drop

+	.quad 0

+1:

+#endif

+die5c:

+	.uleb128 0x3	# (DIE (0x5c) DW_TAG_formal_parameter)

+	.long	.LASF1	# DW_AT_name: "argv"

+	.byte	0x1	# DW_AT_decl_file (py-framefilter-invalidarg.c)

+	.byte	0x1	# DW_AT_decl_line

+	.long	die72-.Ldebug_info0	# DW_AT_type

+	.uleb128 0x2	# DW_AT_location

+	.byte	0x91	# DW_OP_fbreg

+	.sleb128 -32

+	.byte	0	# end of children of DIE 0x2d

+die6b:

+	.uleb128 0x4	# (DIE (0x6b) DW_TAG_base_type)

+	.byte	0x4	# DW_AT_byte_size

+	.byte	0x5	# DW_AT_encoding

+	.ascii "int\0"	# DW_AT_name

+die72:

+	.uleb128 0x5	# (DIE (0x72) DW_TAG_pointer_type)

+	.byte	0x8	# DW_AT_byte_size

+	.long	die78-.Ldebug_info0	# DW_AT_type

+die78:

+	.uleb128 0x5	# (DIE (0x78) DW_TAG_pointer_type)

+	.byte	0x8	# DW_AT_byte_size

+	.long	die7e-.Ldebug_info0	# DW_AT_type

+die7e:

+	.uleb128 0x6	# (DIE (0x7e) DW_TAG_base_type)

+	.byte	0x1	# DW_AT_byte_size

+	.byte	0x6	# DW_AT_encoding

+	.long	.LASF2	# DW_AT_name: "char"

+	.byte	0	# end of children of DIE 0xb

+.Le:

+	.section	.debug_abbrev,"",@progbits

+.Ldebug_abbrev0:

+	.uleb128 0x1	# (abbrev code)

+	.uleb128 0x11	# (TAG: DW_TAG_compile_unit)

+	.byte	0x1	# DW_children_yes

+	.uleb128 0x25	# (DW_AT_producer)

+	.uleb128 0xe	# (DW_FORM_strp)

+	.uleb128 0x13	# (DW_AT_language)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x3	# (DW_AT_name)

+	.uleb128 0xe	# (DW_FORM_strp)

+	.uleb128 0x1b	# (DW_AT_comp_dir)

+	.uleb128 0xe	# (DW_FORM_strp)

+	.uleb128 0x11	# (DW_AT_low_pc)

+	.uleb128 0x1	# (DW_FORM_addr)

+	.uleb128 0x12	# (DW_AT_high_pc)

+	.uleb128 0x7	# (DW_FORM_data8)

+	.uleb128 0x10	# (DW_AT_stmt_list)

+	.uleb128 0x17	# (DW_FORM_sec_offset)

+	.byte	0

+	.byte	0

+	.uleb128 0x2	# (abbrev code)

+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)

+	.byte	0x1	# DW_children_yes

+	.uleb128 0x3f	# (DW_AT_external)

+	.uleb128 0x19	# (DW_FORM_flag_present)

+	.uleb128 0x3	# (DW_AT_name)

+	.uleb128 0xe	# (DW_FORM_strp)

+	.uleb128 0x3a	# (DW_AT_decl_file)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x3b	# (DW_AT_decl_line)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x27	# (DW_AT_prototyped)

+	.uleb128 0x19	# (DW_FORM_flag_present)

+	.uleb128 0x49	# (DW_AT_type)

+	.uleb128 0x13	# (DW_FORM_ref4)

+	.uleb128 0x11	# (DW_AT_low_pc)

+	.uleb128 0x1	# (DW_FORM_addr)

+	.uleb128 0x12	# (DW_AT_high_pc)

+	.uleb128 0x7	# (DW_FORM_data8)

+	.uleb128 0x40	# (DW_AT_frame_base)

+	.uleb128 0x18	# (DW_FORM_exprloc)

+	.uleb128 0x2117	# (DW_AT_GNU_all_call_sites)

+	.uleb128 0x19	# (DW_FORM_flag_present)

+	.byte	0

+	.byte	0

+	.uleb128 0x3	# (abbrev code)

+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)

+	.byte	0	# DW_children_no

+	.uleb128 0x3	# (DW_AT_name)

+	.uleb128 0xe	# (DW_FORM_strp)

+	.uleb128 0x3a	# (DW_AT_decl_file)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x3b	# (DW_AT_decl_line)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x49	# (DW_AT_type)

+	.uleb128 0x13	# (DW_FORM_ref4)

+	.uleb128 0x2	# (DW_AT_location)

+	.uleb128 0x18	# (DW_FORM_exprloc)

+	.byte	0

+	.byte	0

+	.uleb128 0x4	# (abbrev code)

+	.uleb128 0x24	# (TAG: DW_TAG_base_type)

+	.byte	0	# DW_children_no

+	.uleb128 0xb	# (DW_AT_byte_size)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x3e	# (DW_AT_encoding)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x3	# (DW_AT_name)

+	.uleb128 0x8	# (DW_FORM_string)

+	.byte	0

+	.byte	0

+	.uleb128 0x5	# (abbrev code)

+	.uleb128 0xf	# (TAG: DW_TAG_pointer_type)

+	.byte	0	# DW_children_no

+	.uleb128 0xb	# (DW_AT_byte_size)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x49	# (DW_AT_type)

+	.uleb128 0x13	# (DW_FORM_ref4)

+	.byte	0

+	.byte	0

+	.uleb128 0x6	# (abbrev code)

+	.uleb128 0x24	# (TAG: DW_TAG_base_type)

+	.byte	0	# DW_children_no

+	.uleb128 0xb	# (DW_AT_byte_size)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x3e	# (DW_AT_encoding)

+	.uleb128 0xb	# (DW_FORM_data1)

+	.uleb128 0x3	# (DW_AT_name)

+	.uleb128 0xe	# (DW_FORM_strp)

+	.byte	0

+	.byte	0

+	.byte	0

+	.section	.debug_aranges,"",@progbits

+	.long	0x2c	# Length of Address Ranges Info

+	.value	0x2	# DWARF Version

+	.long	.Ldebug_info0	# Offset of Compilation Unit Info

+	.byte	0x8	# Size of Address

+	.byte	0	# Size of Segment Descriptor

+	.value	0	# Pad to 16 byte boundary

+	.value	0

+	.quad	.Ltext0	# Address

+	.quad	.Letext0-.Ltext0	# Length

+	.quad	0

+	.quad	0

+	.section	.debug_line,"",@progbits

+.Ldebug_line0:

+	.section	.debug_str,"MS",@progbits,1

+.LASF1:

+	.string	"argv"

+.LASF4:

+	.string	"py-framefilter-invalidarg.c"

+.LASF5:

+	.string	""

+.LASF0:

+	.string	"argc"

+.LASF3:

+	.string	"GNU C 4.9.1 20140813 (Red Hat 4.9.1-7) -mtune=generic -march=x86-64 -g"

+.LASF6:

+	.string	"main"

+.LASF2:

+	.string	"char"

+	.ident	"GCC: (GNU) 4.9.1 20140813 (Red Hat 4.9.1-7)"

+	.section	.note.GNU-stack,"",@progbits

diff --git a/gdb/testsuite/gdb.python/py-framefilter-invalidarg-gdb.py.in b/gdb/testsuite/gdb.python/py-framefilter-invalidarg-gdb.py.in

new file mode 100644

index 0000000..1fa6ffc

--- /dev/null

+++ b/gdb/testsuite/gdb.python/py-framefilter-invalidarg-gdb.py.in

@@ -0,0 +1,48 @@

+# Copyright (C) 2014 Free Software Foundation, Inc.

+

+# This program is free software; you can redistribute it and/or modify

+# it under the terms of the GNU General Public License as published by

+# the Free Software Foundation; either version 3 of the License, or

+# (at your option) any later version.

+#

+# This program is distributed in the hope that it will be useful,

+# but WITHOUT ANY WARRANTY; without even the implied warranty of

+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+# GNU General Public License for more details.

+#

+# You should have received a copy of the GNU General Public License

+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

+

+# This file is part of the GDB testsuite.  It tests Python-based

+# frame-filters.

+import gdb

+import itertools

+from gdb.FrameDecorator import FrameDecorator

+

+

+class FrameObjFile ():

+

+    def __init__ (self):

+        self.name = "Filter1"

+        self.priority = 1

+        self.enabled = False

+        gdb.current_progspace().frame_filters ["Progspace" + self.name] = self

+        gdb.current_objfile().frame_filters ["ObjectFile" + self.name] = self

+

+    def filter (self, frame_iter):

+        return frame_iter

+

+class FrameObjFile2 ():

+

+    def __init__ (self):

+        self.name = "Filter2"

+        self.priority = 100

+        self.enabled = True

+        gdb.current_progspace().frame_filters ["Progspace" + self.name] = self

+        gdb.current_objfile().frame_filters ["ObjectFile" + self.name] = self

+

+    def filter (self, frame_iter):

+        return frame_iter

+

+FrameObjFile()

+FrameObjFile2()

diff --git a/gdb/testsuite/gdb.python/py-framefilter-invalidarg.exp b/gdb/testsuite/gdb.python/py-framefilter-invalidarg.exp

new file mode 100644

index 0000000..f70d16e

--- /dev/null

+++ b/gdb/testsuite/gdb.python/py-framefilter-invalidarg.exp

@@ -0,0 +1,67 @@

+# Copyright (C) 2014 Free Software Foundation, Inc.

+

+# This program is free software; you can redistribute it and/or modify

+# it under the terms of the GNU General Public License as published by

+# the Free Software Foundation; either version 3 of the License, or

+# (at your option) any later version.

+#

+# This program is distributed in the hope that it will be useful,

+# but WITHOUT ANY WARRANTY; without even the implied warranty of

+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+# GNU General Public License for more details.

+#

+# You should have received a copy of the GNU General Public License

+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

+

+load_lib gdb-python.exp

+

+standard_testfile amd64-py-framefilter-invalidarg.S

+

+if { ![istarget x86_64-*-* ] || ![is_lp64_target] } {

+    verbose "Skipping py-framefilter-invalidarg."

+    return

+}

+

+# We cannot use prepare_for_testing as we have to set the safe-patch

+# to check objfile and progspace printers.

+if {[build_executable $testfile.exp $testfile $srcfile {}] == -1} {

+    return -1

+}

+

+# Start with a fresh gdb.

+gdb_exit

+gdb_start

+

+# Skip all tests if Python scripting is not enabled.

+if { [skip_python_tests] } { continue }

+

+# Make the -gdb.py script available to gdb, it is automagically loaded by gdb.

+# Care is taken to put it in the same directory as the binary so that

+# gdb will find it.

+set remote_obj_python_file \

+    [remote_download \

+	 host ${srcdir}/${subdir}/${testfile}-gdb.py.in \

+	 [standard_output_file ${testfile}-gdb.py]]

+

+gdb_reinitialize_dir $srcdir/$subdir

+gdb_test_no_output "set auto-load safe-path ${remote_obj_python_file}" \

+    "set auto-load safe-path"

+gdb_load ${binfile}

+# Verify gdb loaded the script.

+gdb_test "info auto-load python-scripts" "Yes.*/${testfile}-gdb.py.*" \

+    "Test auto-load had loaded python scripts"

+

+if ![runto_main] then {

+    perror "couldn't run to breakpoint"

+    return

+}

+gdb_test_no_output "set python print-stack full" \

+    "Set python print-stack to full"

+

+# Load global frame-filters

+set remote_python_file [gdb_remote_download host \

+			    ${srcdir}/${subdir}/${testfile}.py]

+gdb_test_no_output "python exec (open ('${remote_python_file}').read ())" \

+    "Load python file"

+

+gdb_test "bt" " in niam \\(argc=<error reading variable: dwarf expression stack underflow>, argv=0x\[0-9a-f\]+\\) at py-framefilter-invalidarg.c:\[0-9\]+" "bt full with filters"

diff --git a/gdb/testsuite/gdb.python/py-framefilter-invalidarg.py b/gdb/testsuite/gdb.python/py-framefilter-invalidarg.py

new file mode 100644

index 0000000..d5f92cb

--- /dev/null

+++ b/gdb/testsuite/gdb.python/py-framefilter-invalidarg.py

@@ -0,0 +1,59 @@

+# Copyright (C) 2014 Free Software Foundation, Inc.

+

+# This program is free software; you can redistribute it and/or modify

+# it under the terms of the GNU General Public License as published by

+# the Free Software Foundation; either version 3 of the License, or

+# (at your option) any later version.

+#

+# This program is distributed in the hope that it will be useful,

+# but WITHOUT ANY WARRANTY; without even the implied warranty of

+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+# GNU General Public License for more details.

+#

+# You should have received a copy of the GNU General Public License

+# along with this program.  If not, see <http://www.gnu.org/licenses/>.

+

+# This file is part of the GDB testsuite.  It tests Python-based

+# frame-filters.

+import gdb

+import itertools

+from gdb.FrameDecorator import FrameDecorator

+import copy

+

+class Reverse_Function (FrameDecorator):

+

+    def __init__(self, fobj):

+        super(Reverse_Function, self).__init__(fobj)

+        self.fobj = fobj

+

+    def function (self):

+        fname = str (self.fobj.function())

+        if (fname == None or fname == ""):

+            return None

+        if fname == 'end_func':

+            extra = self.fobj.inferior_frame().read_var('str').string()

+        else:

+            extra = ''

+        fname = fname[::-1] + extra

+        return fname

+

+class FrameFilter ():

+

+    def __init__ (self):

+        self.name = "Reverse"

+        self.priority = 100

+        self.enabled = True

+        gdb.frame_filters [self.name] = self

+

+    def filter (self, frame_iter):

+        # Python 3.x moved the itertools.imap functionality to map(),

+        # so check if it is available.

+        if hasattr(itertools, "imap"):

+            frame_iter = itertools.imap (Reverse_Function,

+                                         frame_iter)

+        else:

+            frame_iter = map(Reverse_Function, frame_iter)

+

+        return frame_iter

+

+FrameFilter()

--d6Gm4EdcadzBjdND--