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sync with openEuler 2003lts sp1, delete vendor modification.

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Fix CVE-2020-29573, Harden printf against non-normal long double values
This commit is contained in:
wangshuo 2020-12-17 14:44:25 +08:00 committed by liqingqing_1229
parent 5c794b0392
commit deff0486a7
3 changed files with 170 additions and 4 deletions
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128
backport-Fix-CVE-2020-29573-x86-Harden-printf-against-non-normal-long-double-val.patch Normal file
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@ -0,0 +1,128 @@
From 681900d29683722b1cb0a8e565a0585846ec5a61 Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Tue, 22 Sep 2020 19:07:48 +0200
Subject: [PATCH] x86: Harden printf against non-normal long double values (bug
26649)
The behavior of isnan/__builtin_isnan on bit patterns that do not
correspond to something that the CPU would produce from valid inputs
is currently under-defined in the toolchain. (The GCC built-in and
glibc disagree.)
The isnan check in PRINTF_FP_FETCH in stdio-common/printf_fp.c
assumes the GCC behavior that returns true for non-normal numbers
which are not specified as NaN. (The glibc implementation returns
false for such numbers.)
At present, passing non-normal numbers to __mpn_extract_long_double
causes this function to produce irregularly shaped multi-precision
integers, triggering undefined behavior in __printf_fp_l.
With GCC 10 and glibc 2.32, this behavior is not visible because
__builtin_isnan is used, which avoids calling
__mpn_extract_long_double in this case. This commit updates the
implementation of __mpn_extract_long_double so that regularly shaped
multi-precision integers are produced in this case, avoiding
undefined behavior in __printf_fp_l.
---
sysdeps/x86/Makefile | 4 ++
sysdeps/x86/ldbl2mpn.c | 8 ++++
sysdeps/x86/tst-ldbl-nonnormal-printf.c | 52 +++++++++++++++++++++++++
3 files changed, 64 insertions(+)
create mode 100644 sysdeps/x86/tst-ldbl-nonnormal-printf.c
diff --git a/sysdeps/x86/Makefile b/sysdeps/x86/Makefile
index c369faf00d..081cc72e93 100644
--- a/sysdeps/x86/Makefile
+++ b/sysdeps/x86/Makefile
@@ -11,6 +11,10 @@ tests += tst-get-cpu-features tst-get-cpu-features-static \
tests-static += tst-get-cpu-features-static
endif
+ifeq ($(subdir),math)
+tests += tst-ldbl-nonnormal-printf
+endif # $(subdir) == math
+
ifeq ($(subdir),setjmp)
gen-as-const-headers += jmp_buf-ssp.sym
sysdep_routines += __longjmp_cancel
diff --git a/sysdeps/x86/ldbl2mpn.c b/sysdeps/x86/ldbl2mpn.c
index ec8464eef7..23afedfb67 100644
--- a/sysdeps/x86/ldbl2mpn.c
+++ b/sysdeps/x86/ldbl2mpn.c
@@ -115,6 +115,14 @@ __mpn_extract_long_double (mp_ptr res_ptr, mp_size_t size,
&& res_ptr[N - 1] == 0)
/* Pseudo zero. */
*expt = 0;
+ else
+ /* Unlike other floating point formats, the most significant bit
+ is explicit and expected to be set for normal numbers. Set it
+ in case it is cleared in the input. Otherwise, callers will
+ not be able to produce the expected multi-precision integer
+ layout by shifting. */
+ res_ptr[N - 1] |= (mp_limb_t) 1 << (LDBL_MANT_DIG - 1
+ - ((N - 1) * BITS_PER_MP_LIMB));
return N;
}
diff --git a/sysdeps/x86/tst-ldbl-nonnormal-printf.c b/sysdeps/x86/tst-ldbl-nonnormal-printf.c
new file mode 100644
index 0000000000..54381ece0b
--- /dev/null
+++ b/sysdeps/x86/tst-ldbl-nonnormal-printf.c
@@ -0,0 +1,52 @@
+/* Test printf with x86-specific non-normal long double value.
+ Copyright (C) 2020 Free Software Foundation, Inc.
+
+ 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 <stdio.h>
+#include <string.h>
+#include <support/check.h>
+
+/* Fill the stack with non-zero values. This makes a crash in
+ snprintf more likely. */
+static void __attribute__ ((noinline, noclone))
+fill_stack (void)
+{
+ char buffer[65536];
+ memset (buffer, 0xc0, sizeof (buffer));
+ asm ("" ::: "memory");
+}
+
+static int
+do_test (void)
+{
+ fill_stack ();
+
+ long double value;
+ memcpy (&value, "\x00\x04\x00\x00\x00\x00\x00\x00\x00\x04", 10);
+
+ char buf[30];
+ int ret = snprintf (buf, sizeof (buf), "%Lg", value);
+ TEST_COMPARE (ret, strlen (buf));
+ if (strcmp (buf, "nan") != 0)
+ /* If snprintf does not recognize the non-normal number as a NaN,
+ it has added the missing explicit MSB. */
+ TEST_COMPARE_STRING (buf, "3.02201e-4624");
+ return 0;
+}
+
+#include <support/test-driver.c>
--
2.23.0

34
backport-x86-Use-one-ldbl2mpn.c-file-for-both-i386-and-x86_64.patch Normal file
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@ -0,0 +1,34 @@
From 90ccfdf17628e152d96638adc175ae97bd078cfc Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Tue, 22 Sep 2020 17:29:35 +0200
Subject: [PATCH] x86: Use one ldbl2mpn.c file for both i386 and x86_64
---
sysdeps/ia64/ldbl2mpn.c | 2 +-
sysdeps/{i386 => x86}/ldbl2mpn.c | 0
sysdeps/x86_64/ldbl2mpn.c | 1 -
3 files changed, 1 insertion(+), 2 deletions(-)
rename sysdeps/{i386 => x86}/ldbl2mpn.c (100%)
delete mode 100644 sysdeps/x86_64/ldbl2mpn.c
diff --git a/sysdeps/ia64/ldbl2mpn.c b/sysdeps/ia64/ldbl2mpn.c
index 641b789cd4..66ac0a47a4 100644
--- a/sysdeps/ia64/ldbl2mpn.c
+++ b/sysdeps/ia64/ldbl2mpn.c
@@ -1 +1 @@
-#include "../i386/ldbl2mpn.c"
+#include "../x86/ldbl2mpn.c"
diff --git a/sysdeps/i386/ldbl2mpn.c b/sysdeps/x86/ldbl2mpn.c
similarity index 100%
rename from sysdeps/i386/ldbl2mpn.c
rename to sysdeps/x86/ldbl2mpn.c
diff --git a/sysdeps/x86_64/ldbl2mpn.c b/sysdeps/x86_64/ldbl2mpn.c
deleted file mode 100644
index 641b789cd4..0000000000
--- a/sysdeps/x86_64/ldbl2mpn.c
+++ /dev/null
@@ -1 +0,0 @@
-#include "../i386/ldbl2mpn.c"
--
2.23.0

12
glibc.spec
View File

@ -46,9 +46,9 @@
%endif
%define enablekernel 3.2
%define target %{_target_cpu}-%{_vendor}-linux
%define target %{_target_cpu}-openEuler-linux
%ifarch %{arm}
%define target %{_target_cpu}-%{_vendor}-linuxeabi
%define target %{_target_cpu}-openEuler-linuxeabi
%endif
%define x86_arches %{ix86} x86_64
%define all_license LGPLv2+ and LGPLv2+ with exceptions and GPLv2+ and GPLv2+ with exceptions and BSD and Inner-Net and ISC and Public Domain and GFDL
@ -97,6 +97,8 @@ Patch20: backport-0001-Fix-handling-of-collating-symbols-in-fnmatch-bug-266.patc
Patch21: backport-sysvipc-Fix-SEM_STAT_ANY-kernel-argument-pass-BZ-26637.patch
Patch22: backport-i686-tst-strftime3-fix-printf-warning.patch
Patch23: Fix-CVE-2020-27618-iconv-Accept-redundant-shift-sequences.patch
Patch24: backport-x86-Use-one-ldbl2mpn.c-file-for-both-i386-and-x86_64.patch
Patch25: backport-Fix-CVE-2020-29573-x86-Harden-printf-against-non-normal-long-double-val.patch
Provides: ldconfig rtld(GNU_HASH) bundled(gnulib)
@ -1092,8 +1094,10 @@ fi
%doc hesiod/README.hesiod
%changelog
* Fri Jan 8 2021 Wang Shuo<wangshuo_1994@foxmail.com> - 2.28-48
- Replace "openEuler" by %{_vendor} for versatility
* Thu Dec 17 2020 Wang Shuo <wangshuo_1994@foxmail.com> - 2.28-48
- Fix CVE-2020-29573, Harden printf against non-normal long double values
https://cve.mitre.org/cgi-bin/cvename.cgi?name=2020-29573
https://sourceware.org/bugzilla/show_bug.cgi?id=26649
* Tue Nov 10 2020 liusirui<liusirui@huawei.com> - 2.28-47
- Fix CVE-2020-27618, iconv accept redundant shift sequences in IBM1364 [BZ #26224]