@@ -662,6 +662,67 @@ static int dso__synthesize_plt_got_symbols(struct dso *dso, Elf *elf,
return err;
}
+/*
+ * Check dynamic section DT_FLAGS_1 for a Position Independent
+ * Executable (PIE).
+ */
+bool dso__is_pie(struct dso *dso)
+{
+ Elf *elf = NULL;
+ Elf_Scn *scn = NULL;
+ GElf_Ehdr ehdr;
+ GElf_Shdr shdr;
+ bool is_pie = false;
+ char dso_path[PATH_MAX];
+ int fd = -1;
+
+ if (!dso || (elf_version(EV_CURRENT) == EV_NONE))
+ goto exit; // false
+
+ dso__build_id_filename(dso, dso_path, sizeof(dso_path), false);
+
+ fd = open(dso_path, O_RDONLY);
+
+ if (fd < 0) {
+ pr_debug("%s: cannot read cached %s.\n", __func__, dso_path);
+ goto exit; // false
+ }
+
+ elf = elf_begin(fd, ELF_C_READ, NULL);
+ gelf_getehdr(elf, &ehdr);
+
+ if (ehdr.e_type == ET_DYN) {
+ Elf_Data *data;
+ GElf_Dyn *entry;
+ int n_entries = shdr.sh_size / sizeof(GElf_Dyn);
+
+ scn = elf_section_by_name(elf, &ehdr, &shdr, ".dynamic", NULL);
+ if (!scn)
+ goto exit_close; // false
+
+ data = (Elf_Data *) elf_getdata(scn, NULL);
+ if (!data || !data->d_buf)
+ goto exit_close; // false
+
+ // check DT_FLAGS_1
+ for (int i = 0; i < n_entries; i++) {
+ entry = ((GElf_Dyn *) data->d_buf) + i;
+ if (entry->d_tag == DT_FLAGS_1) {
+ if ((entry->d_un.d_val & DF_1_PIE) != 0) {
+ is_pie = true;
+ break;
+ }
+ }
+ } // end for
+ }
+
+exit_close:
+ elf_end(elf);
+ close(fd);
+exit:
+ return is_pie;
+}
+
/*
* We need to check if we have a .dynsym, so that we can handle the
* .plt, synthesizing its symbols, that aren't on the symtabs (be it
@@ -127,6 +127,7 @@ void dso__insert_symbol(struct dso *dso,
struct symbol *sym);
void dso__delete_symbol(struct dso *dso,
struct symbol *sym);
+bool dso__is_pie(struct dso *dso);
struct symbol *dso__find_symbol(struct dso *dso, u64 addr);
struct symbol *dso__find_symbol_nocache(struct dso *dso, u64 addr);