elf: Handle static PIE with non-zero load address [BZ #31799]

For a static PIE with non-zero load address, its PT_DYNAMIC segment
entries contain the relocated values for the load address in static PIE.
Since static PIE usually doesn't have PT_PHDR segment, use p_vaddr of
the PT_LOAD segment with offset == 0 as the load address in static PIE
and adjust the entries of PT_DYNAMIC segment in static PIE by properly
setting the l_addr field for static PIE.  This fixes BZ #31799.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/configure b/configure
index 9c0c0dce03..9bcf62dca5 100755
--- a/configure
+++ b/configure
@@ -8107,6 +8107,80 @@ printf "%s\n" "$libc_cv_cc_pie_default" >&6; }
 config_vars="$config_vars
 cc-pie-default = $libc_cv_cc_pie_default"
 
+# Get Position Dependent Executable (PDE) load address to be used to
+# load static Position Independent Executable (PIE) at a known working
+# non-zero load address.  This is only used by glibc tests to verify
+# that PIE and static PIE with non-zero load address work correctly.
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking PDE load address" >&5
+printf %s "checking PDE load address... " >&6; }
+if test ${libc_cv_pde_load_address+y}
+then :
+  printf %s "(cached) " >&6
+else case e in #(
+  e) cat > conftest.S <<EOF
+.globl _start
+_start:
+.globl __start
+__start:
+EOF
+if test $libc_cv_cc_pie_default = yes; then
+  pde_ld_flags="-no-pie"
+fi
+if ${CC-cc} $pde_ld_flags $CFLAGS $CPPFLAGS $LDFLAGS \
+	    -nostartfiles -nostdlib $no_ssp \
+	    -o conftest conftest.S 1>&5 2>&5; then
+  # Get the load address of the first PT_LOAD segment.
+  libc_cv_pde_load_address=$(LC_ALL=C $READELF -Wl conftest \
+			     | $AWK '/LOAD/ { print $3; exit 0; }')
+else
+  as_fn_error $? "${CC-cc} can not create PDE" "$LINENO" 5
+fi
+rm -f conftest* ;;
+esac
+fi
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $libc_cv_pde_load_address" >&5
+printf "%s\n" "$libc_cv_pde_load_address" >&6; }
+config_vars="$config_vars
+pde-load-address = $libc_cv_pde_load_address"
+
+# Get the linker command-line option to load executable at a non-zero
+# load address.  This is only used by glibc tests to verify that PIE and
+# static PIE with non-zero load address work correctly.
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for linker that supports -Ttext-segment=$libc_cv_pde_load_address" >&5
+printf %s "checking for linker that supports -Ttext-segment=$libc_cv_pde_load_address... " >&6; }
+libc_linker_feature=no
+cat > conftest.c <<EOF
+int _start (void) { return 42; }
+EOF
+if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
+		  -Wl,-Ttext-segment=$libc_cv_pde_load_address -nostdlib -nostartfiles
+		  -fPIC -shared -o conftest.so conftest.c
+		  1>&5'
+  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; }
+then
+  if ${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp -Wl,-Ttext-segment=$libc_cv_pde_load_address -nostdlib \
+      -nostartfiles -fPIC -shared -o conftest.so conftest.c 2>&1 \
+      | grep "warning: -Ttext-segment=$libc_cv_pde_load_address ignored" > /dev/null 2>&1; then
+    true
+  else
+    libc_linker_feature=yes
+  fi
+fi
+rm -f conftest*
+if test $libc_linker_feature = yes; then
+  libc_cv_load_address_ldflag=-Wl,-Ttext-segment
+else
+  libc_cv_load_address_ldflag=
+fi
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $libc_linker_feature" >&5
+printf "%s\n" "$libc_linker_feature" >&6; }
+config_vars="$config_vars
+load-address-ldflag = $libc_cv_load_address_ldflag"
+
 { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking if we can build programs as PIE" >&5
 printf %s "checking if we can build programs as PIE... " >&6; }
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext