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=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 D890DC433EF for ; Fri, 10 Sep 2021 00:20:56 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 746EB611C1 for ; Fri, 10 Sep 2021 00:20:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 746EB611C1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4H5GkH03T3z3cPm for ; Fri, 10 Sep 2021 10:20:55 +1000 (AEST) 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=kh2C/1H5; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=sashal@kernel.org; receiver=) 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=kh2C/1H5; dkim-atps=neutral Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4H5GfT2xxKz2ywX for ; Fri, 10 Sep 2021 10:17:37 +1000 (AEST) Received: by mail.kernel.org (Postfix) with ESMTPSA id 1B1AC6023D; Fri, 10 Sep 2021 00:17:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1631233055; bh=Ld/8iCWO+7pbktr9mXJ2lHwYBZ4/nqPn0oLCMreQlFk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kh2C/1H5n3K9F/9Ew6R+aHpRma2WO92jg0oVLU5SJB0w8LLM7n9pHLQSCh9mVkxNk NFaHxrorRK3TwBYKzfIbpJdk/o5X5DFxly1wMRxSiNGBcud2F+E3gKDzVpuUxhJWtc lK95LKMZTRzHJHi77I19yqf4ZA/YNaxaL21zc5IWqc611tnjiPl4dMDSSUK91sSlUv SLBUZzZ1cxlgAbS1Oy9FLQCKTqfIJ3azT3x5ZwTm99de9XChEzWgu8Fvy8HhT9K+hS 72Zf5jOdEFaNMsNYxKiz50hgraJoiejNevbViwWd8VPthnld7quzxjtfk5a26iCBN7 HCO7TibvzFudg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.14 70/99] powerpc: Avoid link stack corruption in misc asm functions Date: Thu, 9 Sep 2021 20:15:29 -0400 Message-Id: <20210910001558.173296-70-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210910001558.173296-1-sashal@kernel.org> References: <20210910001558.173296-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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: Sasha Levin , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Christophe Leroy [ Upstream commit 33e1402435cb9f3021439a15935ea2dc69ec1844 ] bl;mflr is used at several places to get code position. Use bcl 20,31,+4 instead of bl in order to preserve link stack. See commit c974809a26a1 ("powerpc/vdso: Avoid link stack corruption in __get_datapage()") for details. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/c6eabb4fb6c156f75d56dcbcc6f243e5ac0fba42.1629791763.git.christophe.leroy@csgroup.eu Signed-off-by: Sasha Levin --- arch/powerpc/kernel/misc.S | 2 +- arch/powerpc/kernel/misc_32.S | 2 +- arch/powerpc/kernel/misc_64.S | 2 +- arch/powerpc/kernel/reloc_32.S | 2 +- arch/powerpc/kexec/relocate_32.S | 12 ++++++------ 5 files changed, 10 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/kernel/misc.S b/arch/powerpc/kernel/misc.S index 5be96feccb55..fb7de3543c03 100644 --- a/arch/powerpc/kernel/misc.S +++ b/arch/powerpc/kernel/misc.S @@ -29,7 +29,7 @@ _GLOBAL(reloc_offset) li r3, 0 _GLOBAL(add_reloc_offset) mflr r0 - bl 1f + bcl 20,31,$+4 1: mflr r5 PPC_LL r4,(2f-1b)(r5) subf r5,r4,r5 diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S index 39ab15419592..921d4198bfaa 100644 --- a/arch/powerpc/kernel/misc_32.S +++ b/arch/powerpc/kernel/misc_32.S @@ -67,7 +67,7 @@ _GLOBAL(reloc_got2) srwi. r8,r8,2 beqlr mtctr r8 - bl 1f + bcl 20,31,$+4 1: mflr r0 lis r4,1b@ha addi r4,r4,1b@l diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S index 4b761a18a74d..d38a019b38e1 100644 --- a/arch/powerpc/kernel/misc_64.S +++ b/arch/powerpc/kernel/misc_64.S @@ -255,7 +255,7 @@ _GLOBAL(scom970_write) * Physical (hardware) cpu id should be in r3. */ _GLOBAL(kexec_wait) - bl 1f + bcl 20,31,$+4 1: mflr r5 addi r5,r5,kexec_flag-1b diff --git a/arch/powerpc/kernel/reloc_32.S b/arch/powerpc/kernel/reloc_32.S index 10e96f3e22fe..0508c14b4c28 100644 --- a/arch/powerpc/kernel/reloc_32.S +++ b/arch/powerpc/kernel/reloc_32.S @@ -30,7 +30,7 @@ R_PPC_RELATIVE = 22 _GLOBAL(relocate) mflr r0 /* Save our LR */ - bl 0f /* Find our current runtime address */ + bcl 20,31,$+4 /* Find our current runtime address */ 0: mflr r12 /* Make it accessible */ mtlr r0 diff --git a/arch/powerpc/kexec/relocate_32.S b/arch/powerpc/kexec/relocate_32.S index 61946c19e07c..cf6e52bdf8d8 100644 --- a/arch/powerpc/kexec/relocate_32.S +++ b/arch/powerpc/kexec/relocate_32.S @@ -93,7 +93,7 @@ wmmucr: * Invalidate all the TLB entries except the current entry * where we are running from */ - bl 0f /* Find our address */ + bcl 20,31,$+4 /* Find our address */ 0: mflr r5 /* Make it accessible */ tlbsx r23,0,r5 /* Find entry we are in */ li r4,0 /* Start at TLB entry 0 */ @@ -158,7 +158,7 @@ write_out: /* Switch to other address space in MSR */ insrwi r9, r7, 1, 26 /* Set MSR[IS] = r7 */ - bl 1f + bcl 20,31,$+4 1: mflr r8 addi r8, r8, (2f-1b) /* Find the target offset */ @@ -202,7 +202,7 @@ next_tlb: li r9,0 insrwi r9, r7, 1, 26 /* Set MSR[IS] = r7 */ - bl 1f + bcl 20,31,$+4 1: mflr r8 and r8, r8, r11 /* Get our offset within page */ addi r8, r8, (2f-1b) @@ -240,7 +240,7 @@ setup_map_47x: sync /* Find the entry we are running from */ - bl 2f + bcl 20,31,$+4 2: mflr r23 tlbsx r23, 0, r23 tlbre r24, r23, 0 /* TLB Word 0 */ @@ -296,7 +296,7 @@ clear_utlb_entry: /* Update the msr to the new TS */ insrwi r5, r7, 1, 26 - bl 1f + bcl 20,31,$+4 1: mflr r6 addi r6, r6, (2f-1b) @@ -355,7 +355,7 @@ write_utlb: /* Defaults to 256M */ lis r10, 0x1000 - bl 1f + bcl 20,31,$+4 1: mflr r4 addi r4, r4, (2f-1b) /* virtual address of 2f */ -- 2.30.2