return gate_vma;
}
+static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum,
+ elf_addr_t e_shoff, int segs)
+{
+ elf->e_shoff = e_shoff;
+ elf->e_shentsize = sizeof(*shdr4extnum);
+ elf->e_shnum = 1;
+ elf->e_shstrndx = SHN_UNDEF;
+
+ memset(shdr4extnum, 0, sizeof(*shdr4extnum));
+
+ shdr4extnum->sh_type = SHT_NULL;
+ shdr4extnum->sh_size = elf->e_shnum;
+ shdr4extnum->sh_link = elf->e_shstrndx;
+ shdr4extnum->sh_info = segs;
+}
+
+static size_t elf_core_vma_data_size(struct vm_area_struct *gate_vma,
+ unsigned long mm_flags)
+{
+ struct vm_area_struct *vma;
+ size_t size = 0;
+
+ for (vma = first_vma(current, gate_vma); vma != NULL;
+ vma = next_vma(vma, gate_vma))
+ size += vma_dump_size(vma, mm_flags);
+ return size;
+}
+
/*
* Actual dumper
*
struct vm_area_struct *vma, *gate_vma;
struct elfhdr *elf = NULL;
loff_t offset = 0, dataoff, foffset;
- unsigned long mm_flags;
struct elf_note_info info;
+ struct elf_phdr *phdr4note = NULL;
+ struct elf_shdr *shdr4extnum = NULL;
+ Elf_Half e_phnum;
+ elf_addr_t e_shoff;
/*
* We no longer stop all VM operations.
if (gate_vma != NULL)
segs++;
+ /* for notes section */
+ segs++;
+
+ /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid
+ * this, kernel supports extended numbering. Have a look at
+ * include/linux/elf.h for further information. */
+ e_phnum = segs > PN_XNUM ? PN_XNUM : segs;
+
/*
* Collect all the non-memory information about the process for the
* notes. This also sets up the file header.
*/
- if (!fill_note_info(elf, segs + 1, /* including notes section */
- &info, cprm->signr, cprm->regs))
+ if (!fill_note_info(elf, e_phnum, &info, cprm->signr, cprm->regs))
goto cleanup;
has_dumped = 1;
fs = get_fs();
set_fs(KERNEL_DS);
- size += sizeof(*elf);
- if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
- goto end_coredump;
-
offset += sizeof(*elf); /* Elf header */
- offset += (segs + 1) * sizeof(struct elf_phdr); /* Program headers */
+ offset += segs * sizeof(struct elf_phdr); /* Program headers */
foffset = offset;
/* Write notes phdr entry */
{
- struct elf_phdr phdr;
size_t sz = get_note_info_size(&info);
sz += elf_coredump_extra_notes_size();
- fill_elf_note_phdr(&phdr, sz, offset);
+ phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL);
+ if (!phdr4note)
+ goto end_coredump;
+
+ fill_elf_note_phdr(phdr4note, sz, offset);
offset += sz;
+ }
- size += sizeof(phdr);
- if (size > cprm->limit
- || !dump_write(cprm->file, &phdr, sizeof(phdr)))
+ dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
+
+ offset += elf_core_vma_data_size(gate_vma, cprm->mm_flags);
+ offset += elf_core_extra_data_size();
+ e_shoff = offset;
+
+ if (e_phnum == PN_XNUM) {
+ shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL);
+ if (!shdr4extnum)
goto end_coredump;
+ fill_extnum_info(elf, shdr4extnum, e_shoff, segs);
}
- dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
+ offset = dataoff;
- /*
- * We must use the same mm->flags while dumping core to avoid
- * inconsistency between the program headers and bodies, otherwise an
- * unusable core file can be generated.
- */
- mm_flags = current->mm->flags;
+ size += sizeof(*elf);
+ if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf)))
+ goto end_coredump;
+
+ size += sizeof(*phdr4note);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note)))
+ goto end_coredump;
/* Write program headers for segments dump */
for (vma = first_vma(current, gate_vma); vma != NULL;
phdr.p_offset = offset;
phdr.p_vaddr = vma->vm_start;
phdr.p_paddr = 0;
- phdr.p_filesz = vma_dump_size(vma, mm_flags);
+ phdr.p_filesz = vma_dump_size(vma, cprm->mm_flags);
phdr.p_memsz = vma->vm_end - vma->vm_start;
offset += phdr.p_filesz;
phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
unsigned long addr;
unsigned long end;
- end = vma->vm_start + vma_dump_size(vma, mm_flags);
+ end = vma->vm_start + vma_dump_size(vma, cprm->mm_flags);
for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) {
struct page *page;
if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit))
goto end_coredump;
+ if (e_phnum == PN_XNUM) {
+ size += sizeof(*shdr4extnum);
+ if (size > cprm->limit
+ || !dump_write(cprm->file, shdr4extnum,
+ sizeof(*shdr4extnum)))
+ goto end_coredump;
+ }
+
end_coredump:
set_fs(fs);
cleanup:
free_note_info(&info);
+ kfree(shdr4extnum);
+ kfree(phdr4note);
kfree(elf);
out:
return has_dumped;