[v4,bpf-next,0/5] Add bpf_getxattr

Message

KP Singh June 24, 2022, 4:56 a.m. UTC

v3 -> v4

- Fixed issue incorrect increment of arg counter
- Removed __weak and noinline from kfunc definiton
- Some other minor fixes.

v2 -> v3

- Fixed missing prototype error
- Fixes suggested by other Joanne and Kumar.

v1 -> v2

- Used kfuncs as suggested by Alexei
- Used Benjamin Tissoires' patch from the HID v4 series to add a
  sleepable kfunc set (I sent the patch as a part of this series as it
  seems to have been dropped from v5) and acked it. Hope this is okay.
- Added support for verifying string constants to kfuncs

Foundation for building more complex security policies using the
BPF LSM as presented in LSF/MM/BPF:

 http://vger.kernel.org/bpfconf2022_material/lsfmmbpf2022-xattr.pdf

Benjamin Tissoires (1):
  btf: Add a new kfunc set which allows to mark a function to be
    sleepable

KP Singh (4):
  bpf: kfunc support for ARG_PTR_TO_CONST_STR
  bpf: Allow kfuncs to be used in LSM programs
  bpf: Add a bpf_getxattr kfunc
  bpf/selftests: Add a selftest for bpf_getxattr

 include/linux/bpf_verifier.h                  |  2 +
 include/linux/btf.h                           |  2 +
 kernel/bpf/btf.c                              | 38 +++++++-
 kernel/bpf/verifier.c                         | 89 +++++++++++--------
 kernel/trace/bpf_trace.c                      | 42 +++++++++
 .../testing/selftests/bpf/prog_tests/xattr.c  | 58 ++++++++++++
 tools/testing/selftests/bpf/progs/xattr.c     | 37 ++++++++
 7 files changed, 228 insertions(+), 40 deletions(-)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/xattr.c
 create mode 100644 tools/testing/selftests/bpf/progs/xattr.c

Comments

Christoph Hellwig June 27, 2022, 7:04 a.m. UTC | #1

This needs to have a proper discussin on linux-fsdevel.  Please
resend the whole there.  Adding the lsm list in addition would not be
bad idea either.