VisionFive2 Linux kernel

StarFive Tech Linux Kernel for VisionFive (JH7110) boards (mirror)

More than 9999 Commits   33 Branches   55 Tags
author: Jann Horn <jannh@google.com> 2020-10-15 20:12:50 -0700 committer: Linus Torvalds <torvalds@linux-foundation.org> 2020-10-16 11:11:21 -0700 commit: 429a22e776a2b9f85a2b9c53d8e647598b553dd1 parent: afc63a97b764bc5a715762d0d9cc9785c2ef4e75
Commit Summary:
coredump: rework elf/elf_fdpic vma_dump_size() into common helper
Diffstat:
1 file changed, 0 insertions, 104 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index cf956edf05ef..c1756fd8d10b 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1414,126 +1414,6 @@ out:
  * Jeremy Fitzhardinge <jeremy@sw.oz.au>
  */
 
-/*
- * The purpose of always_dump_vma() is to make sure that special kernel mappings
- * that are useful for post-mortem analysis are included in every core dump.
- * In that way we ensure that the core dump is fully interpretable later
- * without matching up the same kernel and hardware config to see what PC values
- * meant. These special mappings include - vDSO, vsyscall, and other
- * architecture specific mappings
- */
-static bool always_dump_vma(struct vm_area_struct *vma)
-{
-	/* Any vsyscall mappings? */
-	if (vma == get_gate_vma(vma->vm_mm))
-		return true;
-
-	/*
-	 * Assume that all vmas with a .name op should always be dumped.
-	 * If this changes, a new vm_ops field can easily be added.
-	 */
-	if (vma->vm_ops && vma->vm_ops->name && vma->vm_ops->name(vma))
-		return true;
-
-	/*
-	 * arch_vma_name() returns non-NULL for special architecture mappings,
-	 * such as vDSO sections.
-	 */
-	if (arch_vma_name(vma))
-		return true;
-
-	return false;
-}
-
-/*
- * Decide what to dump of a segment, part, all or none.
- */
-static unsigned long vma_dump_size(struct vm_area_struct *vma,
-				   unsigned long mm_flags)
-{
-#define FILTER(type)	(mm_flags & (1UL << MMF_DUMP_##type))
-
-	/* always dump the vdso and vsyscall sections */
-	if (always_dump_vma(vma))
-		goto whole;
-
-	if (vma->vm_flags & VM_DONTDUMP)
-		return 0;
-
-	/* support for DAX */
-	if (vma_is_dax(vma)) {
-		if ((vma->vm_flags & VM_SHARED) && FILTER(DAX_SHARED))
-			goto whole;
-		if (!(vma->vm_flags & VM_SHARED) && FILTER(DAX_PRIVATE))
-			goto whole;
-		return 0;
-	}
-
-	/* Hugetlb memory check */
-	if (is_vm_hugetlb_page(vma)) {
-		if ((vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_SHARED))
-			goto whole;
-		if (!(vma->vm_flags & VM_SHARED) && FILTER(HUGETLB_PRIVATE))
-			goto whole;
-		return 0;
-	}
-
-	/* Do not dump I/O mapped devices or special mappings */
-	if (vma->vm_flags & VM_IO)
-		return 0;
-
-	/* By default, dump shared memory if mapped from an anonymous file. */
-	if (vma->vm_flags & VM_SHARED) {
-		if (file_inode(vma->vm_file)->i_nlink == 0 ?
-		    FILTER(ANON_SHARED) : FILTER(MAPPED_SHARED))
-			goto whole;
-		return 0;
-	}
-
-	/* Dump segments that have been written to.  */
-	if (vma->anon_vma && FILTER(ANON_PRIVATE))
-		goto whole;
-	if (vma->vm_file == NULL)
-		return 0;
-
-	if (FILTER(MAPPED_PRIVATE))
-		goto whole;
-
-	/*
-	 * If this looks like the beginning of a DSO or executable mapping,
-	 * check for an ELF header.  If we find one, dump the first page to
-	 * aid in determining what was mapped here.
-	 */
-	if (FILTER(ELF_HEADERS) &&
-	    vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
-		u32 __user *header = (u32 __user *) vma->vm_start;
-		u32 word;
-		/*
-		 * Doing it this way gets the constant folded by GCC.
-		 */
-		union {
-			u32 cmp;
-			char elfmag[SELFMAG];
-		} magic;
-		BUILD_BUG_ON(SELFMAG != sizeof word);
-		magic.elfmag[EI_MAG0] = ELFMAG0;
-		magic.elfmag[EI_MAG1] = ELFMAG1;
-		magic.elfmag[EI_MAG2] = ELFMAG2;
-		magic.elfmag[EI_MAG3] = ELFMAG3;
-		if (unlikely(get_user(word, header)))
-			word = 0;
-		if (word == magic.cmp)
-			return PAGE_SIZE;
-	}
-
-#undef	FILTER
-
-	return 0;
-
-whole:
-	return vma->vm_end - vma->vm_start;
-}
-
 /* An ELF note in memory */
 struct memelfnote
 {