From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from m16.mail.163.com (m16.mail.163.com [117.135.210.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 266E0480977; Wed, 3 Jun 2026 13:04:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=117.135.210.5 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780491904; cv=none; b=WZWgMR49uYey1xmTP+qGa8ucVpUc2sC3WGu14tSNOVwofiRfrKqjZEkq6fskQlmvPgUV2kQ3YBPHxnEy8kse8Stu9bjsmvo9q23baQoDXWL4bEhhPip5ee2PEC0R+k3CuMtR565BoRWzOljIb6P3t4tgL8y1oPnaO9NNMOkk0vg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780491904; c=relaxed/simple; bh=LBErQI6nA7dzL7B8ktri5f3krdyfYiDJTLqjkqR04bY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=mzAbzMVWNSVLfFDiTbsVSVmUzFB+CmyAqK9Qv0e1T10/Z6y0wfWt95ipthCni33s2aOMnAbB/U5mqV7gE2Xs/XmXU+obP74Bz4qx2SZTmbEPQLbikvB+gEO1U92Fo0BmUjpI2VODURGt+oYuwfZZWIUiFCuNYlsL1i4foMn/wQc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=h5z94MxS; arc=none smtp.client-ip=117.135.210.5 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="h5z94MxS" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=OR mKfkx1an3GTIAvXWkc41xaU079Fl80NRrhqmonOHg=; b=h5z94MxS2/xnJ6CJwL AdhgJShigkFyt3+PEU178oFvo/2QCTGaeVp5OmYzPOi7E6pvcP++uOjla3VQxo+W N7uxeVuPCj/NOgzZyuratxB6AIiBh/q4eCz2t6BJWlYqOvcxnTjWuJt5lp2SAJQl goI/KaFt5bmVe2XpaoWSxqhpM= Received: from China-163-team (unknown []) by gzga-smtp-mtada-g0-4 (Coremail) with SMTP id _____wBnoqAAJiBqWd71BA--.49866S2; Wed, 03 Jun 2026 21:03:04 +0800 (CST) From: Wenshan Lan To: gregkh@linuxfoundation.org, sashal@kernel.org, stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Harshit Mogalapalli , Mimi Zohar , Alexander Graf , Ard Biesheuvel , Borislav Betkov , guoweikang , Henry Willard , "H. Peter Anvin" , Ingo Molnar , Jiri Bohac , Joel Granados , Jonathan McDowell , Mike Rapoport , Paul Webb , Sohil Mehta , Sourabh Jain , Thomas Gleinxer , Yifei Liu , Baoquan He , Andrew Morton , Wenshan Lan Subject: [PATCH 6.6.y 1/3] ima: verify the previous kernel's IMA buffer lies in addressable RAM Date: Wed, 3 Jun 2026 21:02:37 +0800 Message-ID: <20260603130239.81400-1-jetlan9@163.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:_____wBnoqAAJiBqWd71BA--.49866S2 X-Coremail-Antispam: 1Uf129KBjvJXoWxGr1fGw13WF13Ar4fCFy3urg_yoWruFy5pa 9agr4rGrn7Jr1xCws7u3WakF98Xw4kWFy5Wa9xurn7CFy3Jr1DXrsYvrnaqF17tFW3KFyf trsIg3WSg34UXaDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0zi5ku7UUUUU= X-CM-SenderInfo: xmhwztjqz6il2tof0z/xtbC7Aou9mogJgpqPwAA3N From: Harshit Mogalapalli [ Upstream commit 10d1c75ed4382a8e79874379caa2ead8952734f9 ] Patch series "Address page fault in ima_restore_measurement_list()", v3. When the second-stage kernel is booted via kexec with a limiting command line such as "mem=" we observe a pafe fault that happens. BUG: unable to handle page fault for address: ffff97793ff47000 RIP: ima_restore_measurement_list+0xdc/0x45a #PF: error_code(0x0000) not-present page This happens on x86_64 only, as this is already fixed in aarch64 in commit: cbf9c4b9617b ("of: check previous kernel's ima-kexec-buffer against memory bounds") This patch (of 3): When the second-stage kernel is booted with a limiting command line (e.g. "mem="), the IMA measurement buffer handed over from the previous kernel may fall outside the addressable RAM of the new kernel. Accessing such a buffer can fault during early restore. Introduce a small generic helper, ima_validate_range(), which verifies that a physical [start, end] range for the previous-kernel IMA buffer lies within addressable memory: - On x86, use pfn_range_is_mapped(). - On OF based architectures, use page_is_ram(). Link: https://lkml.kernel.org/r/20251231061609.907170-1-harshit.m.mogalapalli@oracle.com Link: https://lkml.kernel.org/r/20251231061609.907170-2-harshit.m.mogalapalli@oracle.com Signed-off-by: Harshit Mogalapalli Reviewed-by: Mimi Zohar Cc: Alexander Graf Cc: Ard Biesheuvel Cc: Borislav Betkov Cc: guoweikang Cc: Henry Willard Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Jiri Bohac Cc: Joel Granados Cc: Jonathan McDowell Cc: Mike Rapoport Cc: Paul Webb Cc: Sohil Mehta Cc: Sourabh Jain Cc: Thomas Gleinxer Cc: Yifei Liu Cc: Baoquan He Cc: Signed-off-by: Andrew Morton Signed-off-by: Wenshan Lan --- include/linux/ima.h | 1 + security/integrity/ima/ima_kexec.c | 35 ++++++++++++++++++++++++++++++ 2 files changed, 36 insertions(+) diff --git a/include/linux/ima.h b/include/linux/ima.h index 86b57757c7b1..1ae8647576ff 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -145,6 +145,7 @@ static inline int ima_measure_critical_data(const char *event_label, #ifdef CONFIG_HAVE_IMA_KEXEC int __init ima_free_kexec_buffer(void); int __init ima_get_kexec_buffer(void **addr, size_t *size); +int ima_validate_range(phys_addr_t phys, size_t size); #endif #ifdef CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c index ad133fe120db..d7c18d8a3103 100644 --- a/security/integrity/ima/ima_kexec.c +++ b/security/integrity/ima/ima_kexec.c @@ -12,6 +12,8 @@ #include #include #include +#include +#include #include "ima.h" #ifdef CONFIG_IMA_KEXEC @@ -164,3 +166,36 @@ void __init ima_load_kexec_buffer(void) pr_debug("Error restoring the measurement list: %d\n", rc); } } + +/* + * ima_validate_range - verify a physical buffer lies in addressable RAM + * @phys: physical start address of the buffer from previous kernel + * @size: size of the buffer + * + * On success return 0. On failure returns -EINVAL so callers can skip + * restoring. + */ +int ima_validate_range(phys_addr_t phys, size_t size) +{ + unsigned long start_pfn, end_pfn; + phys_addr_t end_phys; + + if (check_add_overflow(phys, (phys_addr_t)size - 1, &end_phys)) + return -EINVAL; + + start_pfn = PHYS_PFN(phys); + end_pfn = PHYS_PFN(end_phys); + +#ifdef CONFIG_X86 + if (!pfn_range_is_mapped(start_pfn, end_pfn)) +#else + if (!page_is_ram(start_pfn) || !page_is_ram(end_pfn)) +#endif + { + pr_warn("IMA: previous kernel measurement buffer %pa (size 0x%zx) lies outside available memory\n", + &phys, size); + return -EINVAL; + } + + return 0; +} -- 2.43.0