[PATCH bpf-next v6 0/3] Support kCFI + BPF on arm64

[Maxwell Bland]

Adds CFI checks to BPF dispatchers on aarch64.

E.g.
	<bpf_dispatcher_*_func>:
	paciasp
	stp x29, x30, [sp, #-0x10]!
	mov x29, sp
	+ ldur w16, [x2, #-0x4]
	+ movk w17, #0x1881
	+ movk w17, #0xd942, lsl #16
	+ cmp w16, w17
	+ b.eq <bpf_dispatcher_*_func+0x24>
	+ brk #0x8222
	blr x2
	ldp x29, x30, [sp], #0x10
	autiasp
	ret

Changes in v5->v6
https://lore.kernel.org/all/mafwhrai2nz3u4wn4fu72kvzjm6krs57klc3qqvd2sz2mham6d@x4ukf6xqp4f4/
- Add include for cfi_types, fixing riscv compile error
- Fix authorship sign-off information

Changes in v4->v5
https://lore.kernel.org/all/wtb6czzpvtqq23t4g6hf7on257dtxzdb4fa4nuq3dtq32odmli@xoyyrtthafar/
- Fix failing BPF selftests from misplaced variable declaration

Changes in v3->v4
https://lore.kernel.org/all/fhdcjdzqdqnoehenxbipfaorseeamt3q7fbm7ghe6z5s2chif5@lrhtasolawud/
- Fix authorship attribution.

Changes in v2->v3:
https://lore.kernel.org/all/20240324211518.93892-1-puranjay12@xxxxxxxxx/
- Simplify cfi_get_func_hash to avoid needless failure case
- Use DEFINE_CFI_TYPE as suggested by Mark Rutland

Changes in v1->v2:
https://lore.kernel.org/bpf/20240227151115.4623-1-puranjay12@xxxxxxxxx/
- Rebased on latest bpf-next/master

Mark Rutland (1):
  cfi: add C CFI type macro

Maxwell Bland (1):
  arm64/cfi,bpf: Use DEFINE_CFI_TYPE in arm64

Puranjay Mohan (1):
  arm64/cfi,bpf: Support kCFI + BPF on arm64

 arch/arm64/include/asm/cfi.h    | 23 ++++++++++++++++++++++
 arch/arm64/kernel/alternative.c | 18 +++++++++++++++++
 arch/arm64/net/bpf_jit_comp.c   | 21 +++++++++++++++++---
 arch/riscv/kernel/cfi.c         | 35 +++------------------------------
 arch/x86/kernel/alternative.c   | 35 +++------------------------------
 include/linux/cfi_types.h       | 23 ++++++++++++++++++++++
 6 files changed, 88 insertions(+), 67 deletions(-)
 create mode 100644 arch/arm64/include/asm/cfi.h

-- 

I had one job, make it compile for riscv. Fixed. Thank you again to the
maintainers for their review.

Normally I would wait a week before submitting a new version, but with
the delays on v5, I am submitting sooner to bolster confidence.

2.43.0