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| author | Daniel Borkmann <daniel@iogearbox.net> | 2021-05-31 18:25:46 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-06-10 12:43:52 +0200 |
| commit | b6da354729c770c6ceae5bd96b1708b37b3fce23 (patch) | |
| tree | 145f089a64e6ce097aad94ae90e94293e7c5f4e5 /kernel | |
| parent | b1974c77cb3cb5cf9c9b584af5e7b24617f2ee34 (diff) | |
| download | linux-rt-b6da354729c770c6ceae5bd96b1708b37b3fce23.tar.gz | |
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 4.14]
Signed-off-by: Frank van der Linden <fllinden@amazon.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 d178098f2298..f76177a37b18 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -2110,6 +2110,11 @@ 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, @@ -2510,11 +2515,14 @@ 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; @@ -2534,9 +2542,6 @@ 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 */ |