diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index f8912e45be7ab..0974effff58c0 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -143,9 +143,13 @@ static inline void emit_addr_mov_i64(const int reg, const u64 val, } } -static inline int bpf2a64_offset(int bpf_to, int bpf_from, +static inline int bpf2a64_offset(int bpf_insn, int off, const struct jit_ctx *ctx) { + /* arm64 offset is relative to the branch instruction */ + int bpf_from = bpf_insn + 1; + /* BPF JMP offset is relative to the next instruction */ + int bpf_to = bpf_insn + off + 1; int to = ctx->offset[bpf_to]; /* -1 to account for the Branch instruction */ int from = ctx->offset[bpf_from] - 1; @@ -642,7 +646,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, /* JUMP off */ case BPF_JMP | BPF_JA: - jmp_offset = bpf2a64_offset(i + off, i, ctx); + jmp_offset = bpf2a64_offset(i, off, ctx); check_imm26(jmp_offset); emit(A64_B(jmp_offset), ctx); break; @@ -669,7 +673,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, case BPF_JMP32 | BPF_JSLE | BPF_X: emit(A64_CMP(is64, dst, src), ctx); emit_cond_jmp: - jmp_offset = bpf2a64_offset(i + off, i, ctx); + jmp_offset = bpf2a64_offset(i, off, ctx); check_imm19(jmp_offset); switch (BPF_OP(code)) { case BPF_JEQ: @@ -912,18 +916,26 @@ static int build_body(struct jit_ctx *ctx, bool extra_pass) const struct bpf_insn *insn = &prog->insnsi[i]; int ret; + /* + * offset[0] offset of the end of prologue, start of the + * first insn. + * offset[x] - offset of the end of x insn. + */ + if (ctx->image == NULL) + ctx->offset[i] = ctx->idx; + ret = build_insn(insn, ctx, extra_pass); if (ret > 0) { i++; if (ctx->image == NULL) - ctx->offset[i] = ctx->idx; + ctx->offset[i] = ctx->offset[i - 1]; continue; } - if (ctx->image == NULL) - ctx->offset[i] = ctx->idx; if (ret) return ret; } + if (ctx->image == NULL) + ctx->offset[i] = ctx->idx; return 0; } @@ -1002,7 +1014,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) memset(&ctx, 0, sizeof(ctx)); ctx.prog = prog; - ctx.offset = kcalloc(prog->len, sizeof(int), GFP_KERNEL); + ctx.offset = kcalloc(prog->len + 1, sizeof(int), GFP_KERNEL); if (ctx.offset == NULL) { prog = orig_prog; goto out_off; @@ -1089,7 +1101,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) prog->jited_len = prog_size; if (!prog->is_func || extra_pass) { - bpf_prog_fill_jited_linfo(prog, ctx.offset); + bpf_prog_fill_jited_linfo(prog, ctx.offset + 1); out_off: kfree(ctx.offset); kfree(jit_data);