From patchwork Mon Feb 15 15:27:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 382961 Delivered-To: patch@linaro.org Received: by 2002:a02:c80e:0:0:0:0:0 with SMTP id p14csp1172524jao; Mon, 15 Feb 2021 07:39:44 -0800 (PST) X-Google-Smtp-Source: ABdhPJyG2lGpSMvP627H3vInWtOLy0NiX77AgUIJKrlknx9OOgqFAsau9AMv8KRsZfiXKInwxA1K X-Received: by 2002:a50:f096:: with SMTP id v22mr6267264edl.275.1613403584120; Mon, 15 Feb 2021 07:39:44 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1613403584; cv=none; d=google.com; s=arc-20160816; b=JscstEDKUIhhk96tfC0aVMnS4B5cXtBYYRWeHSbuUJsFsVZ2W+f29/7UIdqyz0VRrL kS7gv2YpuEzsorj+Sbe079/iFMEwJQxG6w66opoMZRCDT3d7wCFltLC4JcRHk7XNAwj8 XSDZDjdsbbyXcXFcyNGV18Y1mwEP5DfF+gqnADv60Vvo8IrPrKU+h9UUx8f4FEvsxLFC fx4MLIJ/mfGbu79ixC+AOoDJ0zoGsPCNuzH7hJoHScryVd+40m0btDXxpyiBecc2Apgc nFif8oHbZHZIsEnHgHKMe48e/2L8OxtDzYXNpgjXKibwnk1IL5FADb8Hj7MR1HnHkU2V ibQw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=SSVxe52Z5DJ7x2Y4XgUuX4TTFhLENf09lPXc3HzwYXQ=; b=0XUJGuaGONmf4oFDlqxlXEaL9Bc9xlHZXyXr+WWerByWVVg4I46yI16v4G2XVPkCaw Dr7d9tJ/DAg5KfcQIGw9yewAfbmInTz5DRl1/S/14KmpCDSxwREJ/sDRbpv/tQqyOxYQ prhoz68Ug9qBKg/AQliANH+SGx/jlHVU9B5+3NZ6tbGVkcYJ3KSqXW/K/q8SwM1tSCVQ VLijCRx0upxK1+q1bKrx1Ig+ceVdOIjBxJLOJ5Axon6wCHY8T9iPYRnCY1fU3QDfpm6T dKb1vC5bM2fZWmB+ViebdzagwAx1XZhPJeOOm0acdVZJr8lAEuBQSZ6H95Gbnbgx58w8 dFBQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=cRhmDT4X; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id x5si12376627ejv.626.2021.02.15.07.39.42; Mon, 15 Feb 2021 07:39:44 -0800 (PST) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=cRhmDT4X; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231448AbhBOPjA (ORCPT + 13 others); Mon, 15 Feb 2021 10:39:00 -0500 Received: from mail.kernel.org ([198.145.29.99]:50308 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231390AbhBOPhV (ORCPT ); Mon, 15 Feb 2021 10:37:21 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 20C5F64E94; Mon, 15 Feb 2021 15:32:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1613403149; bh=N7iQosL3JKwRkW9ldYYAmSXSbyFJasnEVSlivJd289U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cRhmDT4XcTNkx+GTKs3m+RgRkH9762IbpJaWmPnlz22ZaLv1FxVBhFlhaIgjzSX3c xRqZJxom8BbSiCu2rdyb0I34dadg76ffvoDEBHDpWntzb6AMltEacSyogq43mRcLDG 8xYn5cFnH+lZjXKJ3xvDr6NR7tboR79VxEzGg7v0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Arnd Bergmann , Kees Cook , Mark Rutland , Stephen Boyd Subject: [PATCH 5.10 047/104] lkdtm: dont move ctors to .rodata Date: Mon, 15 Feb 2021 16:27:00 +0100 Message-Id: <20210215152720.995680282@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210215152719.459796636@linuxfoundation.org> References: <20210215152719.459796636@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mark Rutland commit 3f618ab3323407ee4c6a6734a37eb6e9663ebfb9 upstream. When building with KASAN and LKDTM, clang may implictly generate an asan.module_ctor function in the LKDTM rodata object. The Makefile moves the lkdtm_rodata_do_nothing() function into .rodata by renaming the file's .text section to .rodata, and consequently also moves the ctor function into .rodata, leading to a boot time crash (splat below) when the ctor is invoked by do_ctors(). Let's prevent this by marking the function as noinstr rather than notrace, and renaming the file's .noinstr.text to .rodata. Marking the function as noinstr will prevent tracing and kprobes, and will inhibit any undesireable compiler instrumentation. The ctor function (if any) will be placed in .text and will work correctly. Example splat before this patch is applied: [ 0.916359] Unable to handle kernel execute from non-executable memory at virtual address ffffa0006b60f5ac [ 0.922088] Mem abort info: [ 0.922828] ESR = 0x8600000e [ 0.923635] EC = 0x21: IABT (current EL), IL = 32 bits [ 0.925036] SET = 0, FnV = 0 [ 0.925838] EA = 0, S1PTW = 0 [ 0.926714] swapper pgtable: 4k pages, 48-bit VAs, pgdp=00000000427b3000 [ 0.928489] [ffffa0006b60f5ac] pgd=000000023ffff003, p4d=000000023ffff003, pud=000000023fffe003, pmd=0068000042000f01 [ 0.931330] Internal error: Oops: 8600000e [#1] PREEMPT SMP [ 0.932806] Modules linked in: [ 0.933617] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc7 #2 [ 0.935620] Hardware name: linux,dummy-virt (DT) [ 0.936924] pstate: 40400005 (nZcv daif +PAN -UAO -TCO BTYPE=--) [ 0.938609] pc : asan.module_ctor+0x0/0x14 [ 0.939759] lr : do_basic_setup+0x4c/0x70 [ 0.940889] sp : ffff27b600177e30 [ 0.941815] x29: ffff27b600177e30 x28: 0000000000000000 [ 0.943306] x27: 0000000000000000 x26: 0000000000000000 [ 0.944803] x25: 0000000000000000 x24: 0000000000000000 [ 0.946289] x23: 0000000000000001 x22: 0000000000000000 [ 0.947777] x21: ffffa0006bf4a890 x20: ffffa0006befb6c0 [ 0.949271] x19: ffffa0006bef9358 x18: 0000000000000068 [ 0.950756] x17: fffffffffffffff8 x16: 0000000000000000 [ 0.952246] x15: 0000000000000000 x14: 0000000000000000 [ 0.953734] x13: 00000000838a16d5 x12: 0000000000000001 [ 0.955223] x11: ffff94000da74041 x10: dfffa00000000000 [ 0.956715] x9 : 0000000000000000 x8 : ffffa0006b60f5ac [ 0.958199] x7 : f9f9f9f9f9f9f9f9 x6 : 000000000000003f [ 0.959683] x5 : 0000000000000040 x4 : 0000000000000000 [ 0.961178] x3 : ffffa0006bdc15a0 x2 : 0000000000000005 [ 0.962662] x1 : 00000000000000f9 x0 : ffffa0006bef9350 [ 0.964155] Call trace: [ 0.964844] asan.module_ctor+0x0/0x14 [ 0.965895] kernel_init_freeable+0x158/0x198 [ 0.967115] kernel_init+0x14/0x19c [ 0.968104] ret_from_fork+0x10/0x30 [ 0.969110] Code: 00000003 00000000 00000000 00000000 (00000000) [ 0.970815] ---[ end trace b5339784e20d015c ]--- Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: Kees Cook Acked-by: Kees Cook Signed-off-by: Mark Rutland Link: https://lore.kernel.org/r/20201207170533.10738-1-mark.rutland@arm.com Cc: Stephen Boyd Signed-off-by: Greg Kroah-Hartman --- drivers/misc/lkdtm/Makefile | 2 +- drivers/misc/lkdtm/rodata.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) --- a/drivers/misc/lkdtm/Makefile +++ b/drivers/misc/lkdtm/Makefile @@ -16,7 +16,7 @@ KCOV_INSTRUMENT_rodata.o := n OBJCOPYFLAGS := OBJCOPYFLAGS_rodata_objcopy.o := \ - --rename-section .text=.rodata,alloc,readonly,load + --rename-section .noinstr.text=.rodata,alloc,readonly,load targets += rodata.o rodata_objcopy.o $(obj)/rodata_objcopy.o: $(obj)/rodata.o FORCE $(call if_changed,objcopy) --- a/drivers/misc/lkdtm/rodata.c +++ b/drivers/misc/lkdtm/rodata.c @@ -5,7 +5,7 @@ */ #include "lkdtm.h" -void notrace lkdtm_rodata_do_nothing(void) +void noinstr lkdtm_rodata_do_nothing(void) { /* Does nothing. We just want an architecture agnostic "return". */ }