The existing 'be' and 'le' insns will do conditional bswap
depends on host endianness. This patch implements
unconditional bswap insns.
Signed-off-by: Yonghong Song <yhs@xxxxxx>
---
arch/x86/net/bpf_jit_comp.c | 1 +
kernel/bpf/core.c | 14 ++++++++++++++
kernel/bpf/verifier.c | 2 +-
3 files changed, 16 insertions(+), 1 deletion(-)
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 7c85d1b01931..6385a8d740b0 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -1322,6 +1322,7 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *rw_image
break;
case BPF_ALU | BPF_END | BPF_FROM_BE:
+ case BPF_ALU64 | BPF_END | BPF_FROM_LE:
switch (imm32) {
case 16:
/* Emit 'ror %ax, 8' to swap lower 2 bytes */
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 72ee246ac3af..b59b41a3d07c 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1524,6 +1524,7 @@ EXPORT_SYMBOL_GPL(__bpf_call_base);
INSN_3(ALU64, DIV, X), \
INSN_3(ALU64, MOD, X), \
INSN_2(ALU64, NEG), \
+ INSN_3(ALU64, END, TO_LE), \
/* Immediate based. */ \
INSN_3(ALU64, ADD, K), \
INSN_3(ALU64, SUB, K), \
@@ -1845,6 +1846,19 @@ static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn)
break;
}
CONT;
+ ALU64_END_TO_LE:
+ switch (IMM) {
+ case 16:
+ DST = (__force u16) __swab16(DST);
+ break;
+ case 32:
+ DST = (__force u32) __swab32(DST);
+ break;
+ case 64:
+ DST = (__force u64) __swab64(DST);
+ break;
+ }
+ CONT;
/* CALL */
JMP_CALL:
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 5c5b37b6b39a..d515bfee1a8f 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -12901,7 +12901,7 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
} else {
if (insn->src_reg != BPF_REG_0 || insn->off != 0 ||
(insn->imm != 16 && insn->imm != 32 && insn->imm != 64) ||
- BPF_CLASS(insn->code) == BPF_ALU64) {
+ (BPF_CLASS(insn->code) == BPF_ALU64 && BPF_SRC(insn->code) != BPF_K)) {
verbose(env, "BPF_END uses reserved fields\n");
return -EINVAL;
}
--
2.34.1
