diff options
| author | CoprDistGit <infra@openeuler.org> | 2024-10-15 06:24:53 +0000 |
|---|---|---|
| committer | CoprDistGit <infra@openeuler.org> | 2024-10-15 06:24:53 +0000 |
| commit | 2fb6e0cf79df2056e9750e29669c4633555e74b8 (patch) | |
| tree | a1ad5fd201e579ad1245110c036501053a8794b3 /Avoid-ldbl-96-stack-corruption-from-range-reduction-.patch | |
| parent | 711949a2ac2288db2115787d9d9cca9cef093ccf (diff) | |
automatic import of glibcopeneuler22.03_LTS_SP3
Diffstat (limited to 'Avoid-ldbl-96-stack-corruption-from-range-reduction-.patch')
| -rw-r--r-- | Avoid-ldbl-96-stack-corruption-from-range-reduction-.patch | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/Avoid-ldbl-96-stack-corruption-from-range-reduction-.patch b/Avoid-ldbl-96-stack-corruption-from-range-reduction-.patch new file mode 100644 index 0000000..09522fa --- /dev/null +++ b/Avoid-ldbl-96-stack-corruption-from-range-reduction-.patch @@ -0,0 +1,126 @@ +From 9f997ceca28f0634ad78a1ca95b84265f7801ff4 Mon Sep 17 00:00:00 2001 +From: Joseph Myers <joseph@codesourcery.com> +Date: Wed, 12 Feb 2020 23:31:56 +0000 +Subject: [PATCH] Avoid ldbl-96 stack corruption from range reduction of + pseudo-zero (bug 25487). + +Bug 25487 reports stack corruption in ldbl-96 sinl on a pseudo-zero +argument (an representation where all the significand bits, including +the explicit high bit, are zero, but the exponent is not zero, which +is not a valid representation for the long double type). + +Although this is not a valid long double representation, existing +practice in this area (see bug 4586, originally marked invalid but +subsequently fixed) is that we still seek to avoid invalid memory +accesses as a result, in case of programs that treat arbitrary binary +data as long double representations, although the invalid +representations of the ldbl-96 format do not need to be consistently +handled the same as any particular valid representation. + +This patch makes the range reduction detect pseudo-zero and unnormal +representations that would otherwise go to __kernel_rem_pio2, and +returns a NaN for them instead of continuing with the range reduction +process. (Pseudo-zero and unnormal representations whose unbiased +exponent is less than -1 have already been safely returned from the +function before this point without going through the rest of range +reduction.) Pseudo-zero representations would previously result in +the value passed to __kernel_rem_pio2 being all-zero, which is +definitely unsafe; unnormal representations would previously result in +a value passed whose high bit is zero, which might well be unsafe +since that is not a form of input expected by __kernel_rem_pio2. + +Tested for x86_64. + +(cherry picked from commit 9333498794cde1d5cca518badf79533a24114b6f) +--- + sysdeps/ieee754/ldbl-96/Makefile | 3 ++- + sysdeps/ieee754/ldbl-96/e_rem_pio2l.c | 12 +++++++++ + sysdeps/ieee754/ldbl-96/test-sinl-pseudo.c | 41 ++++++++++++++++++++++++++++++ + 4 files changed, 60 insertions(+), 1 deletion(-) + create mode 100644 sysdeps/ieee754/ldbl-96/test-sinl-pseudo.c + +diff --git a/sysdeps/ieee754/ldbl-96/Makefile b/sysdeps/ieee754/ldbl-96/Makefile +index 995e90d..318628a 100644 +--- a/sysdeps/ieee754/ldbl-96/Makefile ++++ b/sysdeps/ieee754/ldbl-96/Makefile +@@ -17,5 +17,6 @@ + # <https://www.gnu.org/licenses/>. + + ifeq ($(subdir),math) +-tests += test-canonical-ldbl-96 test-totalorderl-ldbl-96 ++tests += test-canonical-ldbl-96 test-totalorderl-ldbl-96 test-sinl-pseudo ++CFLAGS-test-sinl-pseudo.c += -fstack-protector-all + endif +diff --git a/sysdeps/ieee754/ldbl-96/e_rem_pio2l.c b/sysdeps/ieee754/ldbl-96/e_rem_pio2l.c +index 5f74232..bcdf201 100644 +--- a/sysdeps/ieee754/ldbl-96/e_rem_pio2l.c ++++ b/sysdeps/ieee754/ldbl-96/e_rem_pio2l.c +@@ -210,6 +210,18 @@ __ieee754_rem_pio2l (long double x, long double *y) + return 0; + } + ++ if ((i0 & 0x80000000) == 0) ++ { ++ /* Pseudo-zero and unnormal representations are not valid ++ representations of long double. We need to avoid stack ++ corruption in __kernel_rem_pio2, which expects input in a ++ particular normal form, but those representations do not need ++ to be consistently handled like any particular floating-point ++ value. */ ++ y[1] = y[0] = __builtin_nanl (""); ++ return 0; ++ } ++ + /* Split the 64 bits of the mantissa into three 24-bit integers + stored in a double array. */ + exp = j0 - 23; +diff --git a/sysdeps/ieee754/ldbl-96/test-sinl-pseudo.c b/sysdeps/ieee754/ldbl-96/test-sinl-pseudo.c +new file mode 100644 +index 0000000..f59b977 +--- /dev/null ++++ b/sysdeps/ieee754/ldbl-96/test-sinl-pseudo.c +@@ -0,0 +1,41 @@ ++/* Test sinl for pseudo-zeros and unnormals for ldbl-96 (bug 25487). ++ 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 <math.h> ++#include <math_ldbl.h> ++#include <stdint.h> ++ ++static int ++do_test (void) ++{ ++ for (int i = 0; i < 64; i++) ++ { ++ uint64_t sig = i == 63 ? 0 : 1ULL << i; ++ long double ld; ++ SET_LDOUBLE_WORDS (ld, 0x4141, ++ sig >> 32, sig & 0xffffffffULL); ++ /* The requirement is that no stack overflow occurs when the ++ pseudo-zero or unnormal goes through range reduction. */ ++ volatile long double ldr; ++ ldr = sinl (ld); ++ (void) ldr; ++ } ++ return 0; ++} ++ ++#include <support/test-driver.c> +-- +2.7.4 + |
