[Bug 232176] elftoolchain elfcopy/strip incorrectly strips relocations

[bugzilla-noreply at freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=232176

--- Comment #4 from commit-hook at freebsd.org ---
A commit references this bug:

Author: emaste
Date: Sat Oct 13 21:26:07 UTC 2018
New revision: 339350
URL: https://svnweb.freebsd.org/changeset/base/339350

Log:
  elfcopy: delete filter_reloc, it is broken and unnecessary

  elfcopy contained logic to filter individual relocations in STRIP_ALL
  mode.  However, this is not valid; relocations emitted by the linker are
  required, unless they apply to an entire section being removed (which is
  handled by other logic in elfcopy).

  Note that filter_reloc was also buggy: for RELA relocation sections it
  operated on uninitialized rel.r_info resulting in invalid operation.

  The logic most likely needs to be inverted: instead of removing
  relocations because their associated symbols are being removed, we must
  keep symbols referenced by relocations.  That said, in practice we do
  not encounter this code path today: objects being stripped are either
  dynamically linked binaries which retain .dynsym, or static binaries
  with no relocations.

  Just remove filter_reloc.  This fixes certain cases including statically
  linked binaries containing ifuncs.  Stripping binaries with relocations
  referencing removed symbols was already broken, and after this change
  may still be broken in a different way.

  PR:           232176
  Reviewed by:  kaiw, kib, markj
  Approved by:  re (rgrimes)
  MFC after:    1 month
  Sponsored by: The FreeBSD Foundation
  Differential Revision:        https://reviews.freebsd.org/D17519

Changes:
  head/contrib/elftoolchain/elfcopy/sections.c

-- 
You are receiving this mail because:
You are the assignee for the bug.