diff options
-rw-r--r-- | sysdeps/unix/sysv/linux/mips/Makefile | 21 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/mips/configure | 41 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/mips/configure.ac | 32 |
3 files changed, 89 insertions, 5 deletions
diff --git a/sysdeps/unix/sysv/linux/mips/Makefile b/sysdeps/unix/sysv/linux/mips/Makefile index bca11d39e0..a58e6954a7 100644 --- a/sysdeps/unix/sysv/linux/mips/Makefile +++ b/sysdeps/unix/sysv/linux/mips/Makefile @@ -99,14 +99,25 @@ sysdep-dl-routines += dl-static sysdep_routines += dl-vdso endif - -# Supporting non-executable stacks on MIPS requires changes to both -# the Linux kernel and glibc. See -# <https://sourceware.org/ml/libc-alpha/2016-01/msg00567.html> and -# <https://sourceware.org/ml/libc-alpha/2016-01/msg00719.html>. +# If the compiler doesn't use GNU.stack note, +# this test is expected to fail. +ifneq ($(mips-has-gnustack),yes) test-xfail-check-execstack = yes endif +endif ifeq ($(subdir),stdlib) gen-as-const-headers += ucontext_i.sym endif + +ifeq ($(mips-force-execstack),yes) +CFLAGS-.o += -Wa,-execstack +CFLAGS-.os += -Wa,-execstack +CFLAGS-.op += -Wa,-execstack +CFLAGS-.oS += -Wa,-execstack + +ASFLAGS-.o += -Wa,-execstack +ASFLAGS-.os += -Wa,-execstack +ASFLAGS-.op += -Wa,-execstack +ASFLAGS-.oS += -Wa,-execstack +endif diff --git a/sysdeps/unix/sysv/linux/mips/configure b/sysdeps/unix/sysv/linux/mips/configure index a5513fad48..2ec86a3121 100644 --- a/sysdeps/unix/sysv/linux/mips/configure +++ b/sysdeps/unix/sysv/linux/mips/configure @@ -475,3 +475,44 @@ if test -z "$arch_minimum_kernel"; then arch_minimum_kernel=4.5.0 fi fi + +# Check if we are supposed to run on kernels older than 4.8.0. If so, +# force executable stack to avoid potential runtime problems with fpu +# emulation. +# NOTE: The check below assumes that in absence of user-provided minumum_kernel +# we will default to arch_minimum_kernel which is currently less than 4.8.0 for +# all known configurations. If this changes, the check must be updated. +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the compiler must use executable stack" >&5 +$as_echo_n "checking whether the compiler must use executable stack... " >&6; } +if ${libc_cv_mips_force_execstack+:} false; then : + $as_echo_n "(cached) " >&6 +else + libc_cv_mips_force_execstack=no + if test $libc_mips_float = hard; then + if test -n "$minimum_kernel"; then + + min_version=$((`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1 \* 65536 + \2 \* 256 + \3/'`)) + + if test $min_version -lt 264192; then + libc_cv_mips_force_execstack=yes + fi + else + libc_cv_mips_force_execstack=yes + fi + fi +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_mips_force_execstack" >&5 +$as_echo "$libc_cv_mips_force_execstack" >&6; } + +libc_mips_has_gnustack=$libc_cv_as_noexecstack + +if test $libc_cv_mips_force_execstack = yes; then + libc_mips_has_gnustack=no + { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: forcing executable stack for pre-4.8.0 Linux kernels" >&5 +$as_echo "$as_me: WARNING: forcing executable stack for pre-4.8.0 Linux kernels" >&2;} +fi + +config_vars="$config_vars +mips-force-execstack = ${libc_cv_mips_force_execstack}" +config_vars="$config_vars +mips-has-gnustack = ${libc_mips_has_gnustack}" diff --git a/sysdeps/unix/sysv/linux/mips/configure.ac b/sysdeps/unix/sysv/linux/mips/configure.ac index 9147aa4582..3db1b32b08 100644 --- a/sysdeps/unix/sysv/linux/mips/configure.ac +++ b/sysdeps/unix/sysv/linux/mips/configure.ac @@ -134,3 +134,35 @@ if test -z "$arch_minimum_kernel"; then arch_minimum_kernel=4.5.0 fi fi + +# Check if we are supposed to run on kernels older than 4.8.0. If so, +# force executable stack to avoid potential runtime problems with fpu +# emulation. +# NOTE: The check below assumes that in absence of user-provided minumum_kernel +# we will default to arch_minimum_kernel which is currently less than 4.8.0 for +# all known configurations. If this changes, the check must be updated. +AC_CACHE_CHECK([whether the compiler must use executable stack], + libc_cv_mips_force_execstack, [dnl +libc_cv_mips_force_execstack=no + if test $libc_mips_float = hard; then + if test -n "$minimum_kernel"; then + changequote(,) + min_version=$((`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1 \* 65536 + \2 \* 256 + \3/'`)) + changequote([,]) + if test $min_version -lt 264192; then + libc_cv_mips_force_execstack=yes + fi + else + libc_cv_mips_force_execstack=yes + fi + fi]) + +libc_mips_has_gnustack=$libc_cv_as_noexecstack + +if test $libc_cv_mips_force_execstack = yes; then + libc_mips_has_gnustack=no + AC_MSG_WARN([forcing executable stack for pre-4.8.0 Linux kernels]) +fi + +LIBC_CONFIG_VAR([mips-force-execstack],[${libc_cv_mips_force_execstack}]) +LIBC_CONFIG_VAR([mips-has-gnustack],[${libc_mips_has_gnustack}]) |