* Do the same thing for the memory mapping - between
* elf_bss and last_bss is the bss section.
*/
- k = load_addr + eppnt->p_memsz + eppnt->p_vaddr;
+ k = load_addr + eppnt->p_vaddr + eppnt->p_memsz;
if (k > last_bss)
last_bss = k;
}
}
+ /*
+ * Now fill out the bss section: first pad the last page from
+ * the file up to the page boundary, and zero it from elf_bss
+ * up to the end of the page.
+ */
+ if (padzero(elf_bss)) {
+ error = -EFAULT;
+ goto out;
+ }
+ /*
+ * Next, align both the file and mem bss up to the page size,
+ * since this is where elf_bss was just zeroed up to, and where
+ * last_bss will end after the vm_brk() below.
+ */
+ elf_bss = ELF_PAGEALIGN(elf_bss);
+ last_bss = ELF_PAGEALIGN(last_bss);
+ /* Finally, if there is still more bss to allocate, do it. */
if (last_bss > elf_bss) {
- /*
- * Now fill out the bss section. First pad the last page up
- * to the page boundary, and then perform a mmap to make sure
- * that there are zero-mapped pages up to and including the
- * last bss page.
- */
- if (padzero(elf_bss)) {
- error = -EFAULT;
- goto out;
- }
-
- /* What we have mapped so far */
- elf_bss = ELF_PAGESTART(elf_bss + ELF_MIN_ALIGN - 1);
-
- /* Map the last of the bss segment */
error = vm_brk(elf_bss, last_bss - elf_bss);
if (BAD_ADDR(error))
goto out;
current->flags |= PF_RANDOMIZE;
setup_new_exec(bprm);
+ install_exec_creds(bprm);
/* Do this so that we can load the interpreter, if need be. We will
change some of these later */
elf_flags = MAP_PRIVATE | MAP_DENYWRITE | MAP_EXECUTABLE;
vaddr = elf_ppnt->p_vaddr;
+ /*
+ * If we are loading ET_EXEC or we have already performed
+ * the ET_DYN load_addr calculations, proceed normally.
+ */
if (loc->elf_ex.e_type == ET_EXEC || load_addr_set) {
elf_flags |= MAP_FIXED;
} else if (loc->elf_ex.e_type == ET_DYN) {
- /* Try and get dynamic programs out of the way of the
- * default mmap base, as well as whatever program they
- * might try to exec. This is because the brk will
- * follow the loader, and is not movable. */
- load_bias = ELF_ET_DYN_BASE - vaddr;
- if (current->flags & PF_RANDOMIZE)
- load_bias += arch_mmap_rnd();
- load_bias = ELF_PAGESTART(load_bias);
+ /*
+ * This logic is run once for the first LOAD Program
+ * Header for ET_DYN binaries to calculate the
+ * randomization (load_bias) for all the LOAD
+ * Program Headers, and to calculate the entire
+ * size of the ELF mapping (total_size). (Note that
+ * load_addr_set is set to true later once the
+ * initial mapping is performed.)
+ *
+ * There are effectively two types of ET_DYN
+ * binaries: programs (i.e. PIE: ET_DYN with INTERP)
+ * and loaders (ET_DYN without INTERP, since they
+ * _are_ the ELF interpreter). The loaders must
+ * be loaded away from programs since the program
+ * may otherwise collide with the loader (especially
+ * for ET_EXEC which does not have a randomized
+ * position). For example to handle invocations of
+ * "./ld.so someprog" to test out a new version of
+ * the loader, the subsequent program that the
+ * loader loads must avoid the loader itself, so
+ * they cannot share the same load range. Sufficient
+ * room for the brk must be allocated with the
+ * loader as well, since brk must be available with
+ * the loader.
+ *
+ * Therefore, programs are loaded offset from
+ * ELF_ET_DYN_BASE and loaders are loaded into the
+ * independently randomized mmap region (0 load_bias
+ * without MAP_FIXED).
+ */
+ if (elf_interpreter) {
+ load_bias = ELF_ET_DYN_BASE;
+ if (current->flags & PF_RANDOMIZE)
+ load_bias += arch_mmap_rnd();
+ elf_flags |= MAP_FIXED;
+ } else
+ load_bias = 0;
+
+ /*
+ * Since load_bias is used for all subsequent loading
+ * calculations, we must lower it by the first vaddr
+ * so that the remaining calculations based on the
+ * ELF vaddrs will be correctly offset. The result
+ * is then page aligned.
+ */
+ load_bias = ELF_PAGESTART(load_bias - vaddr);
+
total_size = total_mapping_size(elf_phdata,
loc->elf_ex.e_phnum);
if (!total_size) {
goto out;
#endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
- install_exec_creds(bprm);
retval = create_elf_tables(bprm, &loc->elf_ex,
load_addr, interp_load_addr);
if (retval < 0)
goto out_free_ph;
}
- len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
- ELF_MIN_ALIGN - 1);
- bss = eppnt->p_memsz + eppnt->p_vaddr;
- if (bss > len)
- vm_brk(len, bss - len);
+ len = ELF_PAGEALIGN(eppnt->p_filesz + eppnt->p_vaddr);
+ bss = ELF_PAGEALIGN(eppnt->p_memsz + eppnt->p_vaddr);
+ if (bss > len) {
+ error = vm_brk(len, bss - len);
+ if (BAD_ADDR(error))
+ goto out_free_ph;
+ }
error = 0;
out_free_ph:
const struct user_regset *regset = &view->regsets[i];
do_thread_regset_writeback(t->task, regset);
if (regset->core_note_type && regset->get &&
- (!regset->active || regset->active(t->task, regset))) {
+ (!regset->active || regset->active(t->task, regset) > 0)) {
int ret;
size_t size = regset->n * regset->size;
void *data = kmalloc(size, GFP_KERNEL);
goto end_coredump;
}
}
+ dump_truncate(cprm);
if (!elf_core_write_extra_data(cprm))
goto end_coredump;
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