From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757150AbbFQXfF (ORCPT ); Wed, 17 Jun 2015 19:35:05 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:34820 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754585AbbFQWZe (ORCPT ); Wed, 17 Jun 2015 18:25:34 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Zi Shen Lim , Alexei Starovoitov , Catalin Marinas , Xi Wang , Will Deacon , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 043/146] arm64: bpf: fix signedness bug in loading 64-bit immediate Date: Wed, 17 Jun 2015 15:22:28 -0700 Message-Id: <1434579851-1719-44-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1434579851-1719-1-git-send-email-kamal@canonical.com> References: <1434579851-1719-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.19.8-ckt2 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Xi Wang commit 1e4df6b7208140f3c49f316d33a409d3a161f350 upstream. Consider "(u64)insn1.imm << 32 | imm" in the arm64 JIT. Since imm is signed 32-bit, it is sign-extended to 64-bit, losing the high 32 bits. The fix is to convert imm to u32 first, which will be zero-extended to u64 implicitly. Cc: Zi Shen Lim Cc: Alexei Starovoitov Cc: Catalin Marinas Fixes: 30d3d94cc3d5 ("arm64: bpf: add 'load 64-bit immediate' instruction") Signed-off-by: Xi Wang [will: removed non-arm64 bits and redundant casting] Signed-off-by: Will Deacon Signed-off-by: Kamal Mostafa --- arch/arm64/net/bpf_jit_comp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index edba042..dc6a484 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -487,7 +487,7 @@ emit_cond_jmp: return -EINVAL; } - imm64 = (u64)insn1.imm << 32 | imm; + imm64 = (u64)insn1.imm << 32 | (u32)imm; emit_a64_mov_i64(dst, imm64, ctx); return 1; -- 1.9.1