[bpf-next,0/4] bpf: make trusted args nullable

Message

Vadim Fedorenko May 9, 2024, 1:40 p.m. UTC

Current verifier checks for the arg to be nullable after checking for
certain pointer types. It prevents programs to pass NULL to kfunc args
even if they are marked as nullable. This patchset adjusts verifier and
changes bpf crypto kfuncs to allow null for IV parameter which is
optional for some ciphers. Benchmark shows ~4% improvements when there
is no need to initialise 0-sized dynptr.

Vadim Fedorenko (4):
  bpf: verifier: make kfuncs args nullalble
  bpf: crypto: make state and IV dynptr nullable
  selftests: bpf: crypto: use NULL instead of 0-sized dynptr
  selftests: bpf: crypto: adjust bench to use nullable IV

 kernel/bpf/crypto.c                              | 10 +++++-----
 kernel/bpf/verifier.c                            |  6 +++---
 tools/testing/selftests/bpf/progs/crypto_bench.c | 10 ++++------
 .../testing/selftests/bpf/progs/crypto_sanity.c  | 16 ++++------------
 4 files changed, 16 insertions(+), 26 deletions(-)