From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 42D35C63797 for ; Mon, 19 Jul 2021 17:43:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3ACB46113B for ; Mon, 19 Jul 2021 17:43:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359328AbhGSRBW (ORCPT ); Mon, 19 Jul 2021 13:01:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:59626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347712AbhGSPfQ (ORCPT ); Mon, 19 Jul 2021 11:35:16 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D042061492; Mon, 19 Jul 2021 16:12:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626711172; bh=ulJ/G6wjWazRSvOCapZDdOegzo5tfYJMdms8YEZU7Gc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jRZwKDMJpcfFgTKC5cFx1sXnVdvKJYw6eDJ66eyqHxzsd91sxGqsC8vobEgnM/M+m 9lBbglP+th48Pat9QStHiq3Cg7MpitwEtFc6W71FUJgNTNHGo2cCTmkQANqqIN4cUA x/xQ9gLjOnTaUlxZfdC2xYCIWBuS/QeToU93c0H0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jiri Olsa , "Naveen N. Rao" , Michael Ellerman , Sasha Levin Subject: [PATCH 5.13 255/351] powerpc/bpf: Fix detecting BPF atomic instructions Date: Mon, 19 Jul 2021 16:53:21 +0200 Message-Id: <20210719144953.390810559@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210719144944.537151528@linuxfoundation.org> References: <20210719144944.537151528@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Naveen N. Rao [ Upstream commit 419ac821766cbdb9fd85872bb3f1a589df05c94c ] Commit 91c960b0056672 ("bpf: Rename BPF_XADD and prepare to encode other atomics in .imm") converted BPF_XADD to BPF_ATOMIC and added a way to distinguish instructions based on the immediate field. Existing JIT implementations were updated to check for the immediate field and to reject programs utilizing anything more than BPF_ADD (such as BPF_FETCH) in the immediate field. However, the check added to powerpc64 JIT did not look at the correct BPF instruction. Due to this, such programs would be accepted and incorrectly JIT'ed resulting in soft lockups, as seen with the atomic bounds test. Fix this by looking at the correct immediate value. Fixes: 91c960b0056672 ("bpf: Rename BPF_XADD and prepare to encode other atomics in .imm") Reported-by: Jiri Olsa Signed-off-by: Naveen N. Rao Tested-by: Jiri Olsa Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/4117b430ffaa8cd7af042496f87fd7539e4f17fd.1625145429.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin --- arch/powerpc/net/bpf_jit_comp64.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c index 57a8c1153851..94411af24013 100644 --- a/arch/powerpc/net/bpf_jit_comp64.c +++ b/arch/powerpc/net/bpf_jit_comp64.c @@ -667,7 +667,7 @@ emit_clear: * BPF_STX ATOMIC (atomic ops) */ case BPF_STX | BPF_ATOMIC | BPF_W: - if (insn->imm != BPF_ADD) { + if (imm != BPF_ADD) { pr_err_ratelimited( "eBPF filter atomic op code %02x (@%d) unsupported\n", code, i); @@ -689,7 +689,7 @@ emit_clear: PPC_BCC_SHORT(COND_NE, tmp_idx); break; case BPF_STX | BPF_ATOMIC | BPF_DW: - if (insn->imm != BPF_ADD) { + if (imm != BPF_ADD) { pr_err_ratelimited( "eBPF filter atomic op code %02x (@%d) unsupported\n", code, i); -- 2.30.2