Backport the fix for CVE-2021-43396. It is disputed that this is a security 
issue
however the fix applies easily so we may as well.

Signed-off-by: Richard Purdie <richard.pur...@linuxfoundation.org>
---
 .../glibc/glibc/CVE-2021-43396.patch          | 184 ++++++++++++++++++
 meta/recipes-core/glibc/glibc_2.34.bb         |   1 +
 2 files changed, 185 insertions(+)
 create mode 100644 meta/recipes-core/glibc/glibc/CVE-2021-43396.patch

diff --git a/meta/recipes-core/glibc/glibc/CVE-2021-43396.patch 
b/meta/recipes-core/glibc/glibc/CVE-2021-43396.patch
new file mode 100644
index 00000000000..ebea5efd347
--- /dev/null
+++ b/meta/recipes-core/glibc/glibc/CVE-2021-43396.patch
@@ -0,0 +1,184 @@
+From ff012870b2c02a62598c04daa1e54632e020fd7d Mon Sep 17 00:00:00 2001
+From: Nikita Popov <npv1...@gmail.com>
+Date: Tue, 2 Nov 2021 13:21:42 +0500
+Subject: [PATCH] gconv: Do not emit spurious NUL character in ISO-2022-JP-3
+ (bug 28524)
+
+Bugfix 27256 has introduced another issue:
+In conversion from ISO-2022-JP-3 encoding, it is possible
+to force iconv to emit extra NUL character on internal state reset.
+To do this, it is sufficient to feed iconv with escape sequence
+which switches active character set.
+The simplified check 'data->__statep->__count != ASCII_set'
+introduced by the aforementioned bugfix picks that case and
+behaves as if '\0' character has been queued thus emitting it.
+
+To eliminate this issue, these steps are taken:
+* Restore original condition
+'(data->__statep->__count & ~7) != ASCII_set'.
+It is necessary since bits 0-2 may contain
+number of buffered input characters.
+* Check that queued character is not NUL.
+Similar step is taken for main conversion loop.
+
+Bundled test case follows following logic:
+* Try to convert ISO-2022-JP-3 escape sequence
+switching active character set
+* Reset internal state by providing NULL as input buffer
+* Ensure that nothing has been converted.
+
+Signed-off-by: Nikita Popov <npv1...@gmail.com>
+
+CVE: CVE-2021-43396
+Upstream-Status: Backport [ff012870b2c02a62598c04daa1e54632e020fd7d]
+---
+ iconvdata/Makefile        |  5 +++-
+ iconvdata/bug-iconv15.c   | 60 +++++++++++++++++++++++++++++++++++++++
+ iconvdata/iso-2022-jp-3.c | 28 ++++++++++++------
+ 3 files changed, 84 insertions(+), 9 deletions(-)
+ create mode 100644 iconvdata/bug-iconv15.c
+
+Index: git/iconvdata/Makefile
+===================================================================
+--- git.orig/iconvdata/Makefile
++++ git/iconvdata/Makefile
+@@ -1,4 +1,5 @@
+ # Copyright (C) 1997-2021 Free Software Foundation, Inc.
++# Copyright (C) The GNU Toolchain Authors.
+ # This file is part of the GNU C Library.
+ 
+ # The GNU C Library is free software; you can redistribute it and/or
+@@ -74,7 +75,7 @@ ifeq (yes,$(build-shared))
+ tests = bug-iconv1 bug-iconv2 tst-loading tst-e2big tst-iconv4 bug-iconv4 \
+       tst-iconv6 bug-iconv5 bug-iconv6 tst-iconv7 bug-iconv8 bug-iconv9 \
+       bug-iconv10 bug-iconv11 bug-iconv12 tst-iconv-big5-hkscs-to-2ucs4 \
+-      bug-iconv13 bug-iconv14
++      bug-iconv13 bug-iconv14 bug-iconv15
+ ifeq ($(have-thread-library),yes)
+ tests += bug-iconv3
+ endif
+@@ -327,6 +328,8 @@ $(objpfx)bug-iconv12.out: $(addprefix $(
+                         $(addprefix $(objpfx),$(modules.so))
+ $(objpfx)bug-iconv14.out: $(addprefix $(objpfx), $(gconv-modules)) \
+                         $(addprefix $(objpfx),$(modules.so))
++$(objpfx)bug-iconv15.out: $(addprefix $(objpfx), $(gconv-modules)) \
++                        $(addprefix $(objpfx),$(modules.so))
+ 
+ $(objpfx)iconv-test.out: run-iconv-test.sh \
+                        $(addprefix $(objpfx), $(gconv-modules)) \
+Index: git/iconvdata/bug-iconv15.c
+===================================================================
+--- /dev/null
++++ git/iconvdata/bug-iconv15.c
+@@ -0,0 +1,60 @@
++/* Bug 28524: Conversion from ISO-2022-JP-3 with iconv
++   may emit spurious NUL character on state reset.
++   Copyright (C) The GNU Toolchain Authors.
++   This file is part of the GNU C Library.
++
++   The GNU C Library is free software; you can redistribute it and/or
++   modify it under the terms of the GNU Lesser General Public
++   License as published by the Free Software Foundation; either
++   version 2.1 of the License, or (at your option) any later version.
++
++   The GNU C Library 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
++   Lesser General Public License for more details.
++
++   You should have received a copy of the GNU Lesser General Public
++   License along with the GNU C Library; if not, see
++   <https://www.gnu.org/licenses/>.  */
++
++#include <stddef.h>
++#include <iconv.h>
++#include <support/check.h>
++
++static int
++do_test (void)
++{
++  char in[] = "\x1b(I";
++  char *inbuf = in;
++  size_t inleft = sizeof (in) - 1;
++  char out[1];
++  char *outbuf = out;
++  size_t outleft = sizeof (out);
++  iconv_t cd;
++
++  cd = iconv_open ("UTF8", "ISO-2022-JP-3");
++  TEST_VERIFY_EXIT (cd != (iconv_t) -1);
++
++  /* First call to iconv should alter internal state.
++     Now, JISX0201_Kana_set is selected and
++     state value != ASCII_set.  */
++  TEST_VERIFY (iconv (cd, &inbuf, &inleft, &outbuf, &outleft) != (size_t) -1);
++
++  /* No bytes should have been added to
++     the output buffer at this point.  */
++  TEST_VERIFY (outbuf == out);
++  TEST_VERIFY (outleft == sizeof (out));
++
++  /* Second call shall emit spurious NUL character in unpatched glibc.  */
++  TEST_VERIFY (iconv (cd, NULL, NULL, &outbuf, &outleft) != (size_t) -1);
++
++  /* No characters are expected to be produced.  */
++  TEST_VERIFY (outbuf == out);
++  TEST_VERIFY (outleft == sizeof (out));
++
++  TEST_VERIFY_EXIT (iconv_close (cd) != -1);
++
++  return 0;
++}
++
++#include <support/test-driver.c>
+Index: git/iconvdata/iso-2022-jp-3.c
+===================================================================
+--- git.orig/iconvdata/iso-2022-jp-3.c
++++ git/iconvdata/iso-2022-jp-3.c
+@@ -1,5 +1,6 @@
+ /* Conversion module for ISO-2022-JP-3.
+    Copyright (C) 1998-2021 Free Software Foundation, Inc.
++   Copyright (C) The GNU Toolchain Authors.
+    This file is part of the GNU C Library.
+    Contributed by Ulrich Drepper <drep...@cygnus.com>, 1998,
+    and Bruno Haible <br...@clisp.org>, 2002.
+@@ -81,20 +82,31 @@ enum
+    the output state to the initial state.  This has to be done during the
+    flushing.  */
+ #define EMIT_SHIFT_TO_INIT \
+-  if (data->__statep->__count != ASCII_set)                         \
++  if ((data->__statep->__count & ~7) != ASCII_set)                          \
+     {                                                                       \
+       if (FROM_DIRECTION)                                                   \
+       {                                                                     \
+-        if (__glibc_likely (outbuf + 4 <= outend))                          \
++        uint32_t ch = data->__statep->__count >> 6;                         \
++                                                                            \
++        if (__glibc_unlikely (ch != 0))                                     \
+           {                                                                 \
+-            /* Write out the last character.  */                            \
+-            *((uint32_t *) outbuf) = data->__statep->__count >> 6;          \
+-            outbuf += sizeof (uint32_t);                                    \
+-            data->__statep->__count = ASCII_set;                      \
++            if (__glibc_likely (outbuf + 4 <= outend))                      \
++              {                                                             \
++                /* Write out the last character.  */                        \
++                put32u (outbuf, ch);                                        \
++                outbuf += 4;                                                \
++                data->__statep->__count &= 7;                               \
++                data->__statep->__count |= ASCII_set;                       \
++              }                                                             \
++            else                                                            \
++              /* We don't have enough room in the output buffer.  */        \
++              status = __GCONV_FULL_OUTPUT;                                 \
+           }                                                                 \
+         else                                                                \
+-          /* We don't have enough room in the output buffer.  */            \
+-          status = __GCONV_FULL_OUTPUT;                                     \
++          {                                                                 \
++            data->__statep->__count &= 7;                                   \
++            data->__statep->__count |= ASCII_set;                           \
++          }                                                                 \
+       }                                                                     \
+       else                                                                  \
+       {                                                                     \
diff --git a/meta/recipes-core/glibc/glibc_2.34.bb 
b/meta/recipes-core/glibc/glibc_2.34.bb
index 6dc315c3498..72064772789 100644
--- a/meta/recipes-core/glibc/glibc_2.34.bb
+++ b/meta/recipes-core/glibc/glibc_2.34.bb
@@ -58,6 +58,7 @@ SRC_URI =  "${GLIBC_GIT_URI};branch=${SRCBRANCH};name=glibc \
            file://0001-CVE-2021-38604.patch \
            file://0002-CVE-2021-38604.patch \
            
file://0001-fix-create-thread-failed-in-unprivileged-process-BZ-.patch \
+           file://CVE-2021-43396.patch \
            "
 S = "${WORKDIR}/git"
 B = "${WORKDIR}/build-${TARGET_SYS}"
-- 
2.32.0

-=-=-=-=-=-=-=-=-=-=-=-
Links: You receive all messages sent to this group.
View/Reply Online (#158280): 
https://lists.openembedded.org/g/openembedded-core/message/158280
Mute This Topic: https://lists.openembedded.org/mt/87067035/21656
Group Owner: openembedded-core+ow...@lists.openembedded.org
Unsubscribe: https://lists.openembedded.org/g/openembedded-core/unsub 
[arch...@mail-archive.com]
-=-=-=-=-=-=-=-=-=-=-=-

Reply via email to