diff options
Diffstat (limited to 'sysdeps')
-rw-r--r-- | sysdeps/aarch64/configure | 39 | ||||
-rw-r--r-- | sysdeps/aarch64/configure.ac | 21 |
2 files changed, 60 insertions, 0 deletions
diff --git a/sysdeps/aarch64/configure b/sysdeps/aarch64/configure index c637540436..ac3cf6fd36 100644 --- a/sysdeps/aarch64/configure +++ b/sysdeps/aarch64/configure @@ -216,3 +216,42 @@ if test $libc_cv_aarch64_bti = yes; then $as_echo "#define HAVE_AARCH64_BTI 1" >>confdefs.h fi + +# Check if glibc is built with return address signing, i.e. +# if -mbranch-protection=pac-ret is on. We need this because +# pac-ret relies on unwinder support so it's not safe to use +# it in assembly code unconditionally, but there is no +# feature test macro for it in gcc. +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if pac-ret is enabled" >&5 +$as_echo_n "checking if pac-ret is enabled... " >&6; } +if ${libc_cv_aarch64_pac_ret+:} false; then : + $as_echo_n "(cached) " >&6 +else + cat > conftest.c <<EOF +int bar (void); +int foo (void) { return bar () + 1; } +EOF + libc_cv_aarch64_pac_ret=no + if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS -S -o conftest.s conftest.c' + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5 + (eval $ac_try) 2>&5 + ac_status=$? + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5 + test $ac_status = 0; }; } \ + && { ac_try='grep -q -E '\''(hint( | )+25|paciasp)'\'' conftest.s' + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5 + (eval $ac_try) 2>&5 + ac_status=$? + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5 + test $ac_status = 0; }; } + then + libc_cv_aarch64_pac_ret=yes + fi + rm -rf conftest.* +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_aarch64_pac_ret" >&5 +$as_echo "$libc_cv_aarch64_pac_ret" >&6; } +if test $libc_cv_aarch64_pac_ret = yes; then + $as_echo "#define HAVE_AARCH64_PAC_RET 1" >>confdefs.h + +fi diff --git a/sysdeps/aarch64/configure.ac b/sysdeps/aarch64/configure.ac index 2c2817514d..8b042d6d05 100644 --- a/sysdeps/aarch64/configure.ac +++ b/sysdeps/aarch64/configure.ac @@ -40,3 +40,24 @@ LIBC_CONFIG_VAR([aarch64-bti], [$libc_cv_aarch64_bti]) if test $libc_cv_aarch64_bti = yes; then AC_DEFINE(HAVE_AARCH64_BTI) fi + +# Check if glibc is built with return address signing, i.e. +# if -mbranch-protection=pac-ret is on. We need this because +# pac-ret relies on unwinder support so it's not safe to use +# it in assembly code unconditionally, but there is no +# feature test macro for it in gcc. +AC_CACHE_CHECK([if pac-ret is enabled], [libc_cv_aarch64_pac_ret], [dnl + cat > conftest.c <<EOF +int bar (void); +int foo (void) { return bar () + 1; } +EOF + libc_cv_aarch64_pac_ret=no + if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -S -o conftest.s conftest.c]) \ + && AC_TRY_COMMAND([grep -q -E '\''(hint( | )+25|paciasp)'\'' conftest.s]) + then + libc_cv_aarch64_pac_ret=yes + fi + rm -rf conftest.*]) +if test $libc_cv_aarch64_pac_ret = yes; then + AC_DEFINE(HAVE_AARCH64_PAC_RET) +fi |