Re: Update objcopy's --section-alignment option

Re: Update objcopy's --section-alignment option

[Alan Modra]

ubsan: shift exponent 255 is too large for 64-bit type

I should have known oss-fuzz wouldn't be satisfied so easily.  The pef
format allows quite silly section alignments in object files.

	* objcopy.c (setup_section): Limit shift exponent when checking
	vma and lma for alignment.

diff --git a/binutils/objcopy.c b/binutils/objcopy.c
index d9abfdfbb39..d91ba123c01 100644
--- a/binutils/objcopy.c
+++ b/binutils/objcopy.c
@@ -4340,7 +4340,9 @@ setup_section (bfd *ibfd, sec_ptr isection, void *obfdarg)
      and the VMA was not set by the user
      and the section does not have relocations associated with it
      then warn the user.  */
-  if ((osection->vma & (((bfd_vma) 1 << alignment) - 1)) != 0
+  if (osection->vma != 0
+      && (alignment >= sizeof (bfd_vma) * CHAR_BIT
+	  || (osection->vma & (((bfd_vma) 1 << alignment) - 1)) != 0)
       && alignment != bfd_section_alignment (isection)
       && change_section_address == 0
       && ! vma_set_by_user
@@ -4352,7 +4354,9 @@ setup_section (bfd *ibfd, sec_ptr isection, void *obfdarg)
   /* Similar check for a non-aligned LMA.
      FIXME: Since this is only an LMA, maybe it does not matter if
      it is not aligned ?  */
-  if ((osection->lma & (((bfd_vma) 1 << alignment) - 1)) != 0
+  if (osection->lma != 0
+      && (alignment >= sizeof (bfd_vma) * CHAR_BIT
+	  || (osection->lma & (((bfd_vma) 1 << alignment) - 1)) != 0)
       && alignment != bfd_section_alignment (isection)
       && change_section_address == 0
       && ! lma_set_by_user

-- 
Alan Modra
Australia Development Lab, IBM

Re: Update objcopy's --section-alignment option

[Alan Modra]

ubsan: left shift of 1 by 31 places cannot be represented in type 'int'

	* objcopy.c (setup_section): Avoid undefined behaviour when
	checking vma and lma for alignment.

diff --git a/binutils/objcopy.c b/binutils/objcopy.c
index 77ab9080946..d9abfdfbb39 100644
--- a/binutils/objcopy.c
+++ b/binutils/objcopy.c
@@ -4340,7 +4340,7 @@ setup_section (bfd *ibfd, sec_ptr isection, void *obfdarg)
      and the VMA was not set by the user
      and the section does not have relocations associated with it
      then warn the user.  */
-  if (osection->vma & ((1 << alignment) - 1)
+  if ((osection->vma & (((bfd_vma) 1 << alignment) - 1)) != 0
       && alignment != bfd_section_alignment (isection)
       && change_section_address == 0
       && ! vma_set_by_user
@@ -4352,7 +4352,7 @@ setup_section (bfd *ibfd, sec_ptr isection, void *obfdarg)
   /* Similar check for a non-aligned LMA.
      FIXME: Since this is only an LMA, maybe it does not matter if
      it is not aligned ?  */
-  if (osection->lma & ((1 << alignment) - 1)
+  if ((osection->lma & (((bfd_vma) 1 << alignment) - 1)) != 0
       && alignment != bfd_section_alignment (isection)
       && change_section_address == 0
       && ! lma_set_by_user

-- 
Alan Modra
Australia Development Lab, IBM