linux/tools/testing
Jiong Wang 0bae2d4d62 bpf: correct slot_type marking logic to allow more stack slot sharing
Verifier is supposed to support sharing stack slot allocated to ptr with
SCALAR_VALUE for privileged program. However this doesn't happen for some
cases.

The reason is verifier is not clearing slot_type STACK_SPILL for all bytes,
it only clears part of them, while verifier is using:

  slot_type[0] == STACK_SPILL

as a convention to check one slot is ptr type.

So, the consequence of partial clearing slot_type is verifier could treat a
partially overridden ptr slot, which should now be a SCALAR_VALUE slot,
still as ptr slot, and rejects some valid programs.

Before this patch, test_xdp_noinline.o under bpf selftests, bpf_lxc.o and
bpf_netdev.o under Cilium bpf repo, when built with -mattr=+alu32 are
rejected due to this issue. After this patch, they all accepted.

There is no processed insn number change before and after this patch on
Cilium bpf programs.

Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-12-18 14:45:01 -08:00
..
fault-injection License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ktest These commits have either been sitting in my INBOX or have been 2018-04-11 16:42:27 -07:00
nvdimm tools/testing/nvdimm: Align test resources to 128M 2018-12-05 14:11:48 -08:00
radix-tree radix tree: Remove multiorder support 2018-10-21 10:46:48 -04:00
scatterlist tools/testing/scatterlist: Test new __sg_alloc_table_from_pages 2017-09-07 10:54:40 +01:00
selftests bpf: correct slot_type marking logic to allow more stack slot sharing 2018-12-18 14:45:01 -08:00
vsock VSOCK: add tools/testing/vsock/vsock_diag_test 2017-10-05 18:44:17 -07:00