Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755123Ab3COSaG (ORCPT ); Fri, 15 Mar 2013 14:30:06 -0400 Received: from smtp4-g21.free.fr ([212.27.42.4]:47754 "EHLO smtp4-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755045Ab3COSaD (ORCPT ); Fri, 15 Mar 2013 14:30:03 -0400 From: Nicolas Schichan To: Will Drewry , Mircea Gherzan Cc: Nicolas Schichan , Russell King , "David S. Miller" , Daniel Borkmann , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH RFC 3/3] ARM: net: bpf_jit: add support for jitted seccomp filters. Date: Fri, 15 Mar 2013 19:28:43 +0100 Message-Id: <1363372123-8861-4-git-send-email-nschichan@freebox.fr> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1363372123-8861-1-git-send-email-nschichan@freebox.fr> References: <1363372123-8861-1-git-send-email-nschichan@freebox.fr> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2881 Lines: 100 This patch selects HAVE_SECCOMP_FILTER_JIT in the ARM Kconfig file, implements and seccomp_jit_compile() and seccomp_jit_free(), and adds support for BPF_S_ANC_SECCOMP_LD_W instruction. BPF_S_ANC_SECCOMP_LD_W instructions trigger the generation of a call to C function jit_get_seccomp_w(). which is a wrapper around seccomp_bpf_load(). Signed-off-by: Nicolas Schichan --- arch/arm/Kconfig | 1 + arch/arm/net/bpf_jit_32.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 45 insertions(+) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index dedf02b..b3dce17 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -24,6 +24,7 @@ config ARM select HAVE_ARCH_SECCOMP_FILTER select HAVE_ARCH_TRACEHOOK select HAVE_BPF_JIT + select HAVE_SECCOMP_FILTER_JIT select HAVE_C_RECORDMCOUNT select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_API_DEBUG diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c index 0ea29e0..5af21be 100644 --- a/arch/arm/net/bpf_jit_32.c +++ b/arch/arm/net/bpf_jit_32.c @@ -103,6 +103,13 @@ static u64 jit_get_skb_w(struct sk_buff *skb, unsigned offset) return (u64)err << 32 | ntohl(ret); } +#ifdef CONFIG_SECCOMP_FILTER_JIT +static u64 jit_get_seccomp_w(struct sk_buff *skb, unsigned int offset) +{ + return seccomp_bpf_load(offset); +} +#endif + /* * Wrapper that handles both OABI and EABI and assures Thumb2 interworking * (where the assembly routines like __aeabi_uidiv could cause problems). @@ -548,6 +555,16 @@ load_common: emit_err_ret(ARM_COND_NE, ctx); emit(ARM_MOV_R(r_A, ARM_R0), ctx); break; +#ifdef CONFIG_SECCOMP_FILTER_JIT + case BPF_S_ANC_SECCOMP_LD_W: + ctx->seen |= SEEN_CALL; + emit_mov_i(ARM_R3, (u32)jit_get_seccomp_w, ctx); + emit_mov_i(ARM_R0, 0, ctx); + emit_mov_i(ARM_R1, k, ctx); + emit_blx_r(ARM_R3, ctx); + emit(ARM_MOV_R(r_A, ARM_R0), ctx); + break; +#endif case BPF_S_LD_W_IND: load_order = 2; goto load_ind; @@ -956,3 +973,30 @@ void bpf_jit_free(struct sk_filter *fp) schedule_work(work); } } + +#ifdef CONFIG_SECCOMP_FILTER_JIT +void seccomp_jit_compile(struct seccomp_filter *fp) +{ + struct jit_ctx ctx; + + memset(&ctx, 0, sizeof(ctx)); + ctx.prog_len = fp->len; + ctx.prog_insns = fp->insns; + + __bpf_jit_compile(&ctx); + if (ctx.target) + fp->bpf_func = (void*)ctx.target; +} + +void seccomp_jit_free(struct seccomp_filter *fp) +{ + struct work_struct *work; + + if (fp->bpf_func != sk_run_filter) { + work = (struct work_struct *)fp->bpf_func; + + INIT_WORK(work, bpf_jit_free_worker); + schedule_work(work); + } +} +#endif -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/