Lines Matching +full:high +full:- +full:dynamic +full:- +full:range

1 //===-------- cfi.cpp -----------------------------------------------------===//
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This file implements the runtime support for the cross-DSO CFI.
11 //===----------------------------------------------------------------------===//
61 // The rest of the page is unused and re-mapped read-only.
113     uptr aligned_addr = addr & ~(kShadowAlign - 1);
114     uptr p = aligned_addr - (((uptr)v - 1) << kShadowGranularity);
136   // Mark the given address range as unchecked.
138   // Any CFI check with a target in that range will pass.
140   // Mark the given address range as belonging to a library with the given
155   uint16_t *shadow_end = MemToShadow(end - 1, shadow_) + 1;
159                 "Both bytes of the 16-bit value must be the same!");
161          (shadow_end - shadow_begin) * sizeof(*shadow_begin));
165   assert((cfi_check & (kShadowAlign - 1)) == 0);
172   uint16_t *s_end = MemToShadow(end - 1, shadow_) + 1;
173   uint16_t sv = ((begin - cfi_check) >> kShadowGranularity) + 1;
217   const Elf_Dyn *dynamic = nullptr;
218   for (int i = 0; i < info->dlpi_phnum; ++i) {
219     if (info->dlpi_phdr[i].p_type == PT_DYNAMIC) {
220       dynamic =
221           (const Elf_Dyn *)(info->dlpi_addr + info->dlpi_phdr[i].p_vaddr);
225   if (!dynamic) return 0;
227   for (const Elf_Dyn *p = dynamic; p->d_tag != PT_NULL; ++p) {
228     if (p->d_tag == DT_SYMTAB)
229       symtab = p->d_un.d_ptr;
230     else if (p->d_tag == DT_STRTAB)
231       strtab = p->d_un.d_ptr;
232     else if (p->d_tag == DT_STRSZ)
233       strsz = p->d_un.d_ptr;
242   // This excludes VDSO, which has (very high) bogus strtab and symtab pointers.
244   for (phdr_idx = 0; phdr_idx < info->dlpi_phnum; phdr_idx++) {
245     const Elf_Phdr *phdr = &info->dlpi_phdr[phdr_idx];
246     if (phdr->p_type == PT_LOAD) {
247       uptr beg = info->dlpi_addr + phdr->p_vaddr;
248       uptr end = beg + phdr->p_memsz;
254   if (phdr_idx == info->dlpi_phnum) {
264     // lld-produces files, there are other sections between symtab and strtab.
266     if (p->st_name >= strsz) break;
267     char *name = (char*)(strtab + p->st_name);
269       assert(p->st_info == ELF32_ST_INFO(STB_GLOBAL, STT_FUNC) ||
270              p->st_info == ELF32_ST_INFO(STB_WEAK, STT_FUNC));
271       uptr addr = info->dlpi_addr + p->st_value;
281     VReport(1, "Module '%s' __cfi_check %zx\n", info->dlpi_name, cfi_check);
285   for (int i = 0; i < info->dlpi_phnum; i++) {
286     const Elf_Phdr *phdr = &info->dlpi_phdr[i];
287     if (phdr->p_type == PT_LOAD) {
289       // VTables are in the non-executable one.
293       uptr cur_beg = info->dlpi_addr + phdr->p_vaddr;
294       uptr cur_end = cur_beg + phdr->p_memsz;
297         b->Add(cur_beg, cur_end, cfi_check);
299         b->AddUnchecked(cur_beg, cur_end);
319   // Shadow is 2 -> 2**kShadowGranularity.
320   SetShadowSize((vma >> (kShadowGranularity - 1)) + 1);
338   --in_loader;
374   uf->SetDefaults();
396   if (common_flags()->help) {
424 // Maybe a seccomp-bpf filter?
425 // We could insert a high-priority constructor into the library, but that would