Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a1b59e80 authored by Kawai, Hidehiro's avatar Kawai, Hidehiro Committed by Linus Torvalds
Browse files

coredump masking: ELF: enable core dump filtering



This patch enables core dump filtering for ELF-formatted core file.

Signed-off-by: default avatarHidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 3cb4a0bb
Loading
Loading
Loading
Loading
+21 −9
Original line number Diff line number Diff line
@@ -1262,7 +1262,7 @@ static int dump_seek(struct file *file, loff_t off)
 *
 * I think we should skip something. But I am not sure how. H.J.
 */
static int maydump(struct vm_area_struct *vma)
static int maydump(struct vm_area_struct *vma, unsigned long mm_flags)
{
	/* The vma can be set up to tell us the answer directly.  */
	if (vma->vm_flags & VM_ALWAYSDUMP)
@@ -1272,15 +1272,19 @@ static int maydump(struct vm_area_struct *vma)
	if (vma->vm_flags & (VM_IO | VM_RESERVED))
		return 0;

	/* Dump shared memory only if mapped from an anonymous file. */
	if (vma->vm_flags & VM_SHARED)
		return vma->vm_file->f_path.dentry->d_inode->i_nlink == 0;
	/* By default, dump shared memory if mapped from an anonymous file. */
	if (vma->vm_flags & VM_SHARED) {
		if (vma->vm_file->f_path.dentry->d_inode->i_nlink == 0)
			return test_bit(MMF_DUMP_ANON_SHARED, &mm_flags);
		else
			return test_bit(MMF_DUMP_MAPPED_SHARED, &mm_flags);
	}

	/* If it hasn't been written to, don't write it out */
	/* By default, if it hasn't been written to, don't write it out. */
	if (!vma->anon_vma)
		return 0;
		return test_bit(MMF_DUMP_MAPPED_PRIVATE, &mm_flags);

	return 1;
	return test_bit(MMF_DUMP_ANON_PRIVATE, &mm_flags);
}

/* An ELF note in memory */
@@ -1572,6 +1576,7 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file)
#endif
	int thread_status_size = 0;
	elf_addr_t *auxv;
	unsigned long mm_flags;
#ifdef ELF_CORE_WRITE_EXTRA_NOTES
	int extra_notes_size;
#endif
@@ -1715,6 +1720,13 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file)

	dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);

	/*
	 * 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;

	/* Write program headers for segments dump */
	for (vma = first_vma(current, gate_vma); vma != NULL;
			vma = next_vma(vma, gate_vma)) {
@@ -1727,7 +1739,7 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file)
		phdr.p_offset = offset;
		phdr.p_vaddr = vma->vm_start;
		phdr.p_paddr = 0;
		phdr.p_filesz = maydump(vma) ? sz : 0;
		phdr.p_filesz = maydump(vma, mm_flags) ? sz : 0;
		phdr.p_memsz = sz;
		offset += phdr.p_filesz;
		phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
@@ -1771,7 +1783,7 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file)
			vma = next_vma(vma, gate_vma)) {
		unsigned long addr;

		if (!maydump(vma))
		if (!maydump(vma, mm_flags))
			continue;

		for (addr = vma->vm_start;