This series has the ultimate goal of providing a sane stack rlimit when

running set*id processes. To do this, the bprm_secureexec LSM hook is
 collapsed into the bprm_set_creds hook so the secureexec-ness of an exec
 can be determined early enough to make decisions about rlimits and the
 resulting memory layouts. Other logic acting on the secureexec-ness of an
 exec is similarly consolidated. Capabilities needed some special handling,
 but the refactoring removed other special handling, so that was a wash.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 Comment: Kees Cook <[email protected]>
 
 iQIcBAABCgAGBQJZrwRKAAoJEIly9N/cbcAmhboP/iwLbYfWngIJdu3pYKrW+CEg
 uUVY6RNnsumJ5yEhD/yQKXSPmZ8PkC8vexPYvf8TcPOlMRQuhVvdiR0FfSUvkMWy
 pB8ZVCyAV1uSnW4BH61FCxHInrahy8jlvQwnAujvw+FNxhcQjyEGKupOLIMGLioQ
 8G5Ihf+hOjiXRhKbXueQi89n8i4jEI5YTH1RnC+Gsy8jG11EC9BhPddKSMaUKZA3
 HYYqUyV0daYpGuxTOxaRdDO5wb6rlS+B46hqtOsSsIBOQkCjnLCRcdeMCqvXjQmv
 kyZj03cPlUjEHqh3d3nB6utvVWReGf/p986//kQjT1OZPhATbySAu7wUHoLik3dU
 zuexudNTBROf6YXahMxSJp348GS++xoBFARa78402E++U7C4/eoclbLCWAylBwVA
 H+QAHFYRC2WFoskejSYBRPz6HLr1SIaSYMsKbkHqP07zi6p3ic2Uq3XvOP2zL/5p
 l/mXa1Fs2vcDOWPER8a8b9mVkJDvuXj6J11lG+q80UWAWC3sd9GkSwOen80ps3Xo
 /7dd+h2BAJSSVxZQFxd5YCx99mT0ntQZ797PhjxOY6SX/xUdOCAp9x1zDU5OUovP
 q2ty3UTd7tq8h1RnHOnrn9cKmMmI7kpBvEfPGM507cEVjyfsMu2jJtUxN9dXOAkB
 aebEsg3C8M6z5OdGVpWH
 =Yva4
 -----END PGP SIGNATURE-----

Merge tag 'secureexec-v4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull secureexec update from Kees Cook:
 "This series has the ultimate goal of providing a sane stack rlimit
  when running set*id processes.

  To do this, the bprm_secureexec LSM hook is collapsed into the
  bprm_set_creds hook so the secureexec-ness of an exec can be
  determined early enough to make decisions about rlimits and the
  resulting memory layouts. Other logic acting on the secureexec-ness of
  an exec is similarly consolidated. Capabilities needed some special
  handling, but the refactoring removed other special handling, so that
  was a wash"

* tag 'secureexec-v4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  exec: Consolidate pdeath_signal clearing
  exec: Use sane stack rlimit under secureexec
  exec: Consolidate dumpability logic
  smack: Remove redundant pdeath_signal clearing
  exec: Use secureexec for clearing pdeath_signal
  exec: Use secureexec for setting dumpability
  LSM: drop bprm_secureexec hook
  commoncap: Move cap_elevated calculation into bprm_set_creds
  commoncap: Refactor to remove bprm_secureexec hook
  smack: Refactor to remove bprm_secureexec hook
  selinux: Refactor to remove bprm_secureexec hook
  apparmor: Refactor to remove bprm_secureexec hook
  binfmt: Introduce secureexec flag
  exec: Correct comments about "point of no return"
  exec: Rename bprm->cred_prepared to called_set_creds
This commit is contained in:
Linus Torvalds 2017-09-07 20:35:29 -07:00
commit 828f4257d1
16 changed files with 91 additions and 159 deletions

View file

@ -2356,7 +2356,7 @@ static int selinux_bprm_set_creds(struct linux_binprm *bprm)
/* SELinux context only depends on initial program or script and not
* the script interpreter */
if (bprm->cred_prepared)
if (bprm->called_set_creds)
return 0;
old_tsec = current_security();
@ -2442,30 +2442,17 @@ static int selinux_bprm_set_creds(struct linux_binprm *bprm)
/* Clear any possibly unsafe personality bits on exec: */
bprm->per_clear |= PER_CLEAR_ON_SETID;
}
return 0;
}
static int selinux_bprm_secureexec(struct linux_binprm *bprm)
{
const struct task_security_struct *tsec = current_security();
u32 sid, osid;
int atsecure = 0;
sid = tsec->sid;
osid = tsec->osid;
if (osid != sid) {
/* Enable secure mode for SIDs transitions unless
the noatsecure permission is granted between
the two SIDs, i.e. ahp returns 0. */
atsecure = avc_has_perm(osid, sid,
SECCLASS_PROCESS,
PROCESS__NOATSECURE, NULL);
rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
SECCLASS_PROCESS, PROCESS__NOATSECURE,
NULL);
bprm->secureexec |= !!rc;
}
return !!atsecure;
return 0;
}
static int match_file(const void *p, struct file *file, unsigned fd)
@ -6266,7 +6253,6 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec),
LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),