Re: [GIT PULL] security: seccomp changes for v4.21

From: Kees Cook
Date: Mon Jan 07 2019 - 16:09:28 EST


On Mon, Jan 7, 2019 at 2:15 AM Ingo Molnar <mingo@xxxxxxxxxx> wrote:
>
>
> * James Morris <jmorris@xxxxxxxxx> wrote:
>
> > From Kees:
> >
> > "- Add SECCOMP_RET_USER_NOTIF
> >
> > - seccomp fixes for sparse warnings and s390 build (Tycho)"
> >
> >
> >
> > The following changes since commit 1072bd678547f8663cfb81a22fdb50c589e4976e:
> >
> > security: fs: make inode explicitly non-modular (2018-12-12 14:58:51 -0800)
> >
> > are available in the Git repository at:
> >
> > git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security.git next-seccomp
> >
> > for you to fetch changes up to 55b8cbe470d103b44104c64dbf89e5cad525d4e0:
> >
> > Merge tag 'seccomp-next-part2' of https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into next-seccomp (2018-12-17 11:36:26 -0800)
> >
> > ----------------------------------------------------------------
> > James Morris (2):
> > Merge tag 'seccomp-next' of https://git.kernel.org/.../kees/linux into next-seccomp
> > Merge tag 'seccomp-next-part2' of https://git.kernel.org/.../kees/linux into next-seccomp
> >
> > Tycho Andersen (6):
> > seccomp: hoist struct seccomp_data recalculation higher
> > seccomp: switch system call argument type to void *
> > seccomp: add a return code to trap to userspace
> > samples: add an example of seccomp user trap
> > seccomp: fix poor type promotion
> > seccomp, s390: fix build for syscall type change
> >
> > Documentation/ioctl/ioctl-number.txt | 1 +
> > Documentation/userspace-api/seccomp_filter.rst | 84 +++++
> > arch/s390/kernel/compat_wrapper.c | 2 +-
> > include/linux/seccomp.h | 9 +-
> > include/linux/syscalls.h | 2 +-
> > include/uapi/linux/seccomp.h | 40 ++-
> > kernel/seccomp.c | 467 ++++++++++++++++++++++++-
> > samples/seccomp/.gitignore | 1 +
> > samples/seccomp/Makefile | 7 +-
> > samples/seccomp/user-trap.c | 375 ++++++++++++++++++++
> > tools/testing/selftests/seccomp/seccomp_bpf.c | 447 ++++++++++++++++++++++-
> > 11 files changed, 1411 insertions(+), 24 deletions(-)
> > create mode 100644 samples/seccomp/user-trap.c
>
> 32-bit x86 allyesconfig doesn't build:
>
> /usr/bin/ld: i386:x86-64 architecture of input file `samples/seccomp/user-trap.o' is incompatible with i386 output
> /usr/bin/ld: samples/seccomp/user-trap.o: file class ELFCLASS64 incompatible with ELFCLASS32
> /usr/bin/ld: final link failed: File in wrong format
> collect2: error: ld returned 1 exit status
> scripts/Makefile.host:99: recipe for target 'samples/seccomp/user-trap' failed
> make[2]: *** [samples/seccomp/user-trap] Error 1
>
> Is this a known regression?

That looks like something is busted in the samples Makefile? Tycho,
are you able to reproduce this?

-Kees

--
Kees Cook