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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 85528C5AD4C for ; Thu, 23 Nov 2023 07:21:15 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=mR5nk30n; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4SbV0B1Ww1z3dWj for ; Thu, 23 Nov 2023 18:21:14 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=mR5nk30n; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=139.178.84.217; helo=dfw.source.kernel.org; envelope-from=naveen@kernel.org; receiver=lists.ozlabs.org) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4SbTzD6GvTz3dKp for ; Thu, 23 Nov 2023 18:20:24 +1100 (AEDT) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id A732661237; Thu, 23 Nov 2023 07:20:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70982C433C7; Thu, 23 Nov 2023 07:20:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700724021; bh=fCVzGTxShoC9pNOu5C9KTDEl4vJb5zh/T8fNSbBa2d4=; h=From:To:Cc:Subject:Date:From; b=mR5nk30nrMArge+b7uUqLdTv320tFUQJwDTlKnoydBG8xtTE8Ngv1bhQXWnMUUJks lqYIIyo5X15/0X6ejmDNSg8+4pvoiyLpaacs44BX/j8cZWyJByHVmVVsZTcs8nEJcv w62A8LhsKMPnuPW6BxMezFwZT8VsUPlfBJWuZqMT3Fr/ELN2vm9tvy6l3Od+8McWcY s4Sip5XFHhRLJVcD11dH4dkd6qdVvVH8EITuirlbwAxSHQd+96tiAEzXrQtLF7H8zP +fIUEpuAm/vaWebotVJGu2Ten0Sb8NwxMJwxMHRkR31enyl7NrN2Pc5vZGo8InzjrK VMCrazTBL15sw== From: Naveen N Rao To: Michael Ellerman Subject: [PATCH] powerpc/lib: Validate size for vector operations Date: Thu, 23 Nov 2023 12:47:05 +0530 Message-ID: <20231123071705.397625-1-naveen@kernel.org> X-Mailer: git-send-email 2.42.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Some of the fp/vmx code in sstep.c assume a certain maximum size for the instructions being emulated. The size of those operations however is determined separately in analyse_instr(). Add a check to validate the assumption on the maximum size of the operations, so as to prevent any unintended kernel stack corruption. Signed-off-by: Naveen N Rao --- arch/powerpc/lib/sstep.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index a13f05cfc7db..5766180f5380 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -586,6 +586,8 @@ static int do_fp_load(struct instruction_op *op, unsigned long ea, } u; nb = GETSIZE(op->type); + if (nb > sizeof(u)) + return -EINVAL; if (!address_ok(regs, ea, nb)) return -EFAULT; rn = op->reg; @@ -636,6 +638,8 @@ static int do_fp_store(struct instruction_op *op, unsigned long ea, } u; nb = GETSIZE(op->type); + if (nb > sizeof(u)) + return -EINVAL; if (!address_ok(regs, ea, nb)) return -EFAULT; rn = op->reg; @@ -680,6 +684,9 @@ static nokprobe_inline int do_vec_load(int rn, unsigned long ea, u8 b[sizeof(__vector128)]; } u = {}; + if (size > sizeof(u)) + return -EINVAL; + if (!address_ok(regs, ea & ~0xfUL, 16)) return -EFAULT; /* align to multiple of size */ @@ -707,6 +714,9 @@ static nokprobe_inline int do_vec_store(int rn, unsigned long ea, u8 b[sizeof(__vector128)]; } u; + if (size > sizeof(u)) + return -EINVAL; + if (!address_ok(regs, ea & ~0xfUL, 16)) return -EFAULT; /* align to multiple of size */ base-commit: 275f51172646ac48f0c4e690c72183084fd996d1 prerequisite-patch-id: ebc3edfe2b9fce7bdf27098c8631740153249b06 -- 2.42.0