diff options
author | Yonghong Song <yonghong.song@linux.dev> | 2023-06-29 01:29:51 +0300 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2023-07-28 04:54:02 +0300 |
commit | f835bb6222998c8655bc4e85287d42b57c17b208 (patch) | |
tree | ee72f6b3b326a938a682674e27e8974d27356a50 /kernel/bpf | |
parent | 4cd58e9af8b9d9fff6b7145e742abbfcda0af4af (diff) | |
download | linux-f835bb6222998c8655bc4e85287d42b57c17b208.tar.xz |
bpf: Add kernel/bpftool asm support for new instructions
Add asm support for new instructions so kernel verifier and bpftool
xlated insn dumps can have proper asm syntax for new instructions.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/bpf')
-rw-r--r-- | kernel/bpf/disasm.c | 57 |
1 files changed, 51 insertions, 6 deletions
diff --git a/kernel/bpf/disasm.c b/kernel/bpf/disasm.c index 7b4afb7d96db..d7bff608f299 100644 --- a/kernel/bpf/disasm.c +++ b/kernel/bpf/disasm.c @@ -87,6 +87,17 @@ const char *const bpf_alu_string[16] = { [BPF_END >> 4] = "endian", }; +const char *const bpf_alu_sign_string[16] = { + [BPF_DIV >> 4] = "s/=", + [BPF_MOD >> 4] = "s%=", +}; + +const char *const bpf_movsx_string[4] = { + [0] = "(s8)", + [1] = "(s16)", + [3] = "(s32)", +}; + static const char *const bpf_atomic_alu_string[16] = { [BPF_ADD >> 4] = "add", [BPF_AND >> 4] = "and", @@ -101,6 +112,12 @@ static const char *const bpf_ldst_string[] = { [BPF_DW >> 3] = "u64", }; +static const char *const bpf_ldsx_string[] = { + [BPF_W >> 3] = "s32", + [BPF_H >> 3] = "s16", + [BPF_B >> 3] = "s8", +}; + static const char *const bpf_jmp_string[16] = { [BPF_JA >> 4] = "jmp", [BPF_JEQ >> 4] = "==", @@ -128,6 +145,26 @@ static void print_bpf_end_insn(bpf_insn_print_t verbose, insn->imm, insn->dst_reg); } +static void print_bpf_bswap_insn(bpf_insn_print_t verbose, + void *private_data, + const struct bpf_insn *insn) +{ + verbose(private_data, "(%02x) r%d = bswap%d r%d\n", + insn->code, insn->dst_reg, + insn->imm, insn->dst_reg); +} + +static bool is_sdiv_smod(const struct bpf_insn *insn) +{ + return (BPF_OP(insn->code) == BPF_DIV || BPF_OP(insn->code) == BPF_MOD) && + insn->off == 1; +} + +static bool is_movsx(const struct bpf_insn *insn) +{ + return BPF_OP(insn->code) == BPF_MOV && insn->off != 0; +} + void print_bpf_insn(const struct bpf_insn_cbs *cbs, const struct bpf_insn *insn, bool allow_ptr_leaks) @@ -138,7 +175,7 @@ void print_bpf_insn(const struct bpf_insn_cbs *cbs, if (class == BPF_ALU || class == BPF_ALU64) { if (BPF_OP(insn->code) == BPF_END) { if (class == BPF_ALU64) - verbose(cbs->private_data, "BUG_alu64_%02x\n", insn->code); + print_bpf_bswap_insn(verbose, cbs->private_data, insn); else print_bpf_end_insn(verbose, cbs->private_data, insn); } else if (BPF_OP(insn->code) == BPF_NEG) { @@ -147,17 +184,20 @@ void print_bpf_insn(const struct bpf_insn_cbs *cbs, insn->dst_reg, class == BPF_ALU ? 'w' : 'r', insn->dst_reg); } else if (BPF_SRC(insn->code) == BPF_X) { - verbose(cbs->private_data, "(%02x) %c%d %s %c%d\n", + verbose(cbs->private_data, "(%02x) %c%d %s %s%c%d\n", insn->code, class == BPF_ALU ? 'w' : 'r', insn->dst_reg, - bpf_alu_string[BPF_OP(insn->code) >> 4], + is_sdiv_smod(insn) ? bpf_alu_sign_string[BPF_OP(insn->code) >> 4] + : bpf_alu_string[BPF_OP(insn->code) >> 4], + is_movsx(insn) ? bpf_movsx_string[(insn->off >> 3) - 1] : "", class == BPF_ALU ? 'w' : 'r', insn->src_reg); } else { verbose(cbs->private_data, "(%02x) %c%d %s %d\n", insn->code, class == BPF_ALU ? 'w' : 'r', insn->dst_reg, - bpf_alu_string[BPF_OP(insn->code) >> 4], + is_sdiv_smod(insn) ? bpf_alu_sign_string[BPF_OP(insn->code) >> 4] + : bpf_alu_string[BPF_OP(insn->code) >> 4], insn->imm); } } else if (class == BPF_STX) { @@ -218,13 +258,15 @@ void print_bpf_insn(const struct bpf_insn_cbs *cbs, verbose(cbs->private_data, "BUG_st_%02x\n", insn->code); } } else if (class == BPF_LDX) { - if (BPF_MODE(insn->code) != BPF_MEM) { + if (BPF_MODE(insn->code) != BPF_MEM && BPF_MODE(insn->code) != BPF_MEMSX) { verbose(cbs->private_data, "BUG_ldx_%02x\n", insn->code); return; } verbose(cbs->private_data, "(%02x) r%d = *(%s *)(r%d %+d)\n", insn->code, insn->dst_reg, - bpf_ldst_string[BPF_SIZE(insn->code) >> 3], + BPF_MODE(insn->code) == BPF_MEM ? + bpf_ldst_string[BPF_SIZE(insn->code) >> 3] : + bpf_ldsx_string[BPF_SIZE(insn->code) >> 3], insn->src_reg, insn->off); } else if (class == BPF_LD) { if (BPF_MODE(insn->code) == BPF_ABS) { @@ -279,6 +321,9 @@ void print_bpf_insn(const struct bpf_insn_cbs *cbs, } else if (insn->code == (BPF_JMP | BPF_JA)) { verbose(cbs->private_data, "(%02x) goto pc%+d\n", insn->code, insn->off); + } else if (insn->code == (BPF_JMP32 | BPF_JA)) { + verbose(cbs->private_data, "(%02x) gotol pc%+d\n", + insn->code, insn->imm); } else if (insn->code == (BPF_JMP | BPF_EXIT)) { verbose(cbs->private_data, "(%02x) exit\n", insn->code); } else if (BPF_SRC(insn->code) == BPF_X) { |