Fix/aarch64 optimization relro (#3)

* Implemented improvements but real bug is not solved.

* Add docker command for testing.

Author: viferga

.dockerignore

@@ -0,0 +1,15 @@
+**
+!plthook_elf.c
+!plthook_osx.c
+!plthook_win32.c
+!plthook.h
+!test
+test/*.obj
+test/libtest.dll
+test/libtest.exp
+test/libtest.lib
+test/libtest.so
+test/testprog
+test/testprog.exe
+test/dummy.c
+test/dummy.o

Dockerfile

@@ -0,0 +1,35 @@
+# Dockerfile for QEMU testing
+# docker build -t metacall/plthook .
+FROM ubuntu:latest
+
+RUN apt update \
+    && apt install -y \
+        make \
+        qemu-user \
+        gcc-arm-linux-gnueabi \
+        gcc-arm-linux-gnueabihf \
+        gcc-aarch64-linux-gnu \
+        gcc-powerpc-linux-gnu \
+        gcc-powerpc64le-linux-gnu \
+        gcc-riscv64-linux-gnu \
+        libc6-dev-armhf-cross \
+        libc6-dev-ppc64el-cross \
+        libc6-dev-powerpc-cross \
+        libc6-dev-armel-cross \
+        libc6-dev-arm64-cross
+
+WORKDIR /plthook
+
+COPY . .
+
+WORKDIR /plthook/test
+
+ENV OPT_CFLAGS="-O3"
+
+RUN echo "Running tests" \
+    && make relro_pie_tests TARGET_PLATFORM=aarch64-linux-gnu \
+    && make relro_pie_tests TARGET_PLATFORM=arm-linux-gnueabi \
+    && make relro_pie_tests TARGET_PLATFORM=arm-linux-gnueabihf \
+    && make relro_pie_tests TARGET_PLATFORM=powerpc-linux-gnu QEMU_ARCH=ppc \
+    && make relro_pie_tests TARGET_PLATFORM=powerpc64le-linux-gnu QEMU_ARCH=ppc64le \
+    && make relro_pie_tests TARGET_PLATFORM=riscv64-linux-gnu QEMU_ARCH=riscv64

plthook_elf.c

@@ -683,14 +683,14 @@ static int plthook_open_real(plthook_t **plthook_out, struct link_map *lmap)
             set_errmsg("failed to find PLT_DT_RELSZ");
             return PLTHOOK_INTERNAL_ERROR;
         }
-        total_size = dyn->d_un.d_ptr;
+        total_size = dyn->d_un.d_val;
 
         dyn = find_dyn_by_tag(lmap->l_ld, PLT_DT_RELENT);
         if (dyn == NULL) {
             set_errmsg("failed to find PLT_DT_RELENT");
             return PLTHOOK_INTERNAL_ERROR;
         }
-        elem_size = dyn->d_un.d_ptr;
+        elem_size = dyn->d_un.d_val;
         plthook.rela_dyn_cnt = total_size / elem_size;
     }
 #endif

test/testprog.c

@@ -90,7 +90,7 @@ static void reset_result(void)
 
 static void set_result(hooked_val_t *hv, const char *str, double result)
 {
-    strncpy(hv->str, str, sizeof(hv->str));
+    strncpy(hv->str, str, sizeof(hv->str) - 1);
     hv->result = result;
 }