diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2021-05-28 13:38:04 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-06-03 08:38:07 +0200 |
| commit | 7d2617351898876e6e51f010f3abe8000226583e (patch) | |
| tree | 6236895fa9526af30b16a97b0b3d87e96e83de55 /kernel | |
| parent | 8827288cb63949f5d79f84feaf2f7baf35d484fd (diff) | |
bpf: Move sanitize_val_alu out of op switch
commit f528819334881fd622fdadeddb3f7edaed8b7c9b upstream.
Add a small sanitize_needed() helper function and move sanitize_val_alu()
out of the main opcode switch. In upcoming work, we'll move sanitize_ptr_alu()
as well out of its opcode switch so this helps to streamline both.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
[fllinden@amazon.com: backported to 5.4]
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/verifier.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index faa2a4c3467d..094f70876923 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2815,6 +2815,11 @@ static int sanitize_val_alu(struct bpf_verifier_env *env, return update_alu_sanitation_state(aux, BPF_ALU_NON_POINTER, 0); } +static bool sanitize_needed(u8 opcode) +{ + return opcode == BPF_ADD || opcode == BPF_SUB; +} + static int sanitize_ptr_alu(struct bpf_verifier_env *env, struct bpf_insn *insn, const struct bpf_reg_state *ptr_reg, @@ -3207,11 +3212,14 @@ static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env, return 0; } - switch (opcode) { - case BPF_ADD: + if (sanitize_needed(opcode)) { ret = sanitize_val_alu(env, insn); if (ret < 0) return sanitize_err(env, insn, ret, NULL, NULL); + } + + switch (opcode) { + case BPF_ADD: if (signed_add_overflows(dst_reg->smin_value, smin_val) || signed_add_overflows(dst_reg->smax_value, smax_val)) { dst_reg->smin_value = S64_MIN; @@ -3231,9 +3239,6 @@ static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env, dst_reg->var_off = tnum_add(dst_reg->var_off, src_reg.var_off); break; case BPF_SUB: - ret = sanitize_val_alu(env, insn); - if (ret < 0) - return sanitize_err(env, insn, ret, NULL, NULL); if (signed_sub_overflows(dst_reg->smin_value, smax_val) || signed_sub_overflows(dst_reg->smax_value, smin_val)) { /* Overflow possible, we know nothing */ |