Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964801AbbHDNU7 (ORCPT ); Tue, 4 Aug 2015 09:20:59 -0400 Received: from smtp3-g21.free.fr ([212.27.42.3]:33917 "EHLO smtp3-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934180AbbHDNUJ (ORCPT ); Tue, 4 Aug 2015 09:20:09 -0400 From: Nicolas Schichan To: Daniel Borkmann , Alexei Starovoitov , "David S. Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Nicolas Schichan Subject: [PATCH V2 net-next 6/6] test_bpf: add tests checking that JIT/interpreter sets A and X to 0. Date: Tue, 4 Aug 2015 15:19:12 +0200 Message-Id: <1438694352-17469-7-git-send-email-nschichan@freebox.fr> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1438694352-17469-1-git-send-email-nschichan@freebox.fr> References: <1438694352-17469-1-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: 3827 Lines: 189 It is mandatory for the JIT or interpreter to reset the A and X registers to 0 before running the filter. Check that it is the case on various ALU and JMP instructions. Signed-off-by: Nicolas Schichan Acked-by: Alexei Starovoitov Acked-by: Daniel Borkmann --- lib/test_bpf.c | 158 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 158 insertions(+) diff --git a/lib/test_bpf.c b/lib/test_bpf.c index e6ef56d..d137739 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -4931,6 +4931,164 @@ static struct bpf_test tests[] = { }, { {0x40, 0x88ee99ff } }, }, + /* + * verify that the interpreter or JIT correctly sets A and X + * to 0. + */ + { + "ADD default X", + .u.insns = { + /* + * A = 0x42 + * A = A + X + * ret A + */ + BPF_STMT(BPF_LD | BPF_IMM, 0x42), + BPF_STMT(BPF_ALU | BPF_ADD | BPF_X, 0), + BPF_STMT(BPF_RET | BPF_A, 0x0), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x42 } }, + }, + { + "ADD default A", + .u.insns = { + /* + * A = A + 0x42 + * ret A + */ + BPF_STMT(BPF_ALU | BPF_ADD | BPF_K, 0x42), + BPF_STMT(BPF_RET | BPF_A, 0x0), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x42 } }, + }, + { + "SUB default X", + .u.insns = { + /* + * A = 0x66 + * A = A - X + * ret A + */ + BPF_STMT(BPF_LD | BPF_IMM, 0x66), + BPF_STMT(BPF_ALU | BPF_SUB | BPF_X, 0), + BPF_STMT(BPF_RET | BPF_A, 0x0), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x66 } }, + }, + { + "SUB default A", + .u.insns = { + /* + * A = A - -0x66 + * ret A + */ + BPF_STMT(BPF_ALU | BPF_SUB | BPF_K, -0x66), + BPF_STMT(BPF_RET | BPF_A, 0x0), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x66 } }, + }, + { + "MUL default X", + .u.insns = { + /* + * A = 0x42 + * A = A * X + * ret A + */ + BPF_STMT(BPF_LD | BPF_IMM, 0x42), + BPF_STMT(BPF_ALU | BPF_MUL | BPF_X, 0), + BPF_STMT(BPF_RET | BPF_A, 0x0), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x0 } }, + }, + { + "MUL default A", + .u.insns = { + /* + * A = A * 0x66 + * ret A + */ + BPF_STMT(BPF_ALU | BPF_MUL | BPF_K, 0x66), + BPF_STMT(BPF_RET | BPF_A, 0x0), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x0 } }, + }, + { + "DIV default X", + .u.insns = { + /* + * A = 0x42 + * A = A / X ; this halt the filter execution if X is 0 + * ret 0x42 + */ + BPF_STMT(BPF_LD | BPF_IMM, 0x42), + BPF_STMT(BPF_ALU | BPF_DIV | BPF_X, 0), + BPF_STMT(BPF_RET | BPF_K, 0x42), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x0 } }, + }, + { + "DIV default A", + .u.insns = { + /* + * A = A / 1 + * ret A + */ + BPF_STMT(BPF_ALU | BPF_DIV | BPF_K, 0x1), + BPF_STMT(BPF_RET | BPF_A, 0x0), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x0 } }, + }, + { + "JMP EQ default A", + .u.insns = { + /* + * cmp A, 0x0, 0, 1 + * ret 0x42 + * ret 0x66 + */ + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x0, 0, 1), + BPF_STMT(BPF_RET | BPF_K, 0x42), + BPF_STMT(BPF_RET | BPF_K, 0x66), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x42 } }, + }, + { + "JMP EQ default X", + .u.insns = { + /* + * A = 0x0 + * cmp A, X, 0, 1 + * ret 0x42 + * ret 0x66 + */ + BPF_STMT(BPF_LD | BPF_IMM, 0x0), + BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_X, 0x0, 0, 1), + BPF_STMT(BPF_RET | BPF_K, 0x42), + BPF_STMT(BPF_RET | BPF_K, 0x66), + }, + CLASSIC | FLAG_NO_DATA, + {}, + { {0x1, 0x42 } }, + }, }; static struct net_device dev; -- 1.9.1 -- 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/