diff options
| author | Alexei Starovoitov <ast@kernel.org> | 2020-09-17 19:09:18 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-09-17 19:56:07 -0700 |
| commit | 09b28d76eac48e922dc293da1aa2b2b85c32aeee (patch) | |
| tree | 2be3e375d9a88923b63ac9c3fda927d25073483a /include/linux | |
| parent | e411901c0b775a3ae7f3e2505f8d2d90ac696178 (diff) | |
bpf: Add abnormal return checks.
LD_[ABS|IND] instructions may return from the function early. bpf_tail_call
pseudo instruction is either fallthrough or return. Allow them in the
subprograms only when subprograms are BTF annotated and have scalar return
types. Allow ld_abs and tail_call in the main program even if it calls into
subprograms. In the past that was not ok to do for ld_abs, since it was JITed
with special exit sequence. Since bpf_gen_ld_abs() was introduced the ld_abs
looks like normal exit insn from JIT point of view, so it's safe to allow them
in the main program.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/bpf_verifier.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index fbc964526ba3..2bb48a2c4d08 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -360,6 +360,7 @@ struct bpf_subprog_info { u16 stack_depth; /* max. stack depth used by this function */ bool has_tail_call; bool tail_call_reachable; + bool has_ld_abs; }; /* single container for all structs |