From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 9B8B3302779; Sun, 1 Mar 2026 01:52:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772329931; cv=none; b=YmxHDmaOXdAmeI/0Cts+wczke5V9+xW7v1rw6h3SpdD71P/U6mwRqDgklKU3LTthWpnlCRczWurpjbdyFjlaNW11XKruO7IRuqjOhcMBDboZQICJ9I4oZtWwhdCw/6CZh84BVfArs+527NHk4QEKX2+2kB82apY1NshK/bi947o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772329931; c=relaxed/simple; bh=Nw1EeV+g4V1IczrQgKHIeaJciH2dqCdwotGsG/MlDPg=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=TZ8VWEUoATGV70JhICcLNqhZnAQyhPxBBTt+4Qvx3hePDwwFp/mMJUfzx7bAdk8WADDZ950bSt1vFNH4iPLwjO94IpBeVInHZYdwEWEGnsDUbppqNSsgOaRDFYcdiR48Q0M/ZMv8HGfOEalNIysfUawetf/N1hhtswCzuQL933w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CMSEbp5v; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CMSEbp5v" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5B228C19421; Sun, 1 Mar 2026 01:52:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772329931; bh=Nw1EeV+g4V1IczrQgKHIeaJciH2dqCdwotGsG/MlDPg=; h=From:To:Cc:Subject:Date:From; b=CMSEbp5vNJ+3fPOApzGcQAvZKskjGRJr0y0jDtLXZSroE58GTnXw1A0y7RrcHz+eS cX+r/Mqm9MSceM0Tjcs24Im112usUQcqqkc16NVzJDMKj4ORxNyqL+jD2H57/Nf9Ti 5CRNFx9aKU4NC/KwviJilYhkYImuNeDcFVzuZaWoE4QgMzQ6A1rYCwG8mOZA0DKkqT pE1CVkaPyDsDT3wrMgv2U7mToMS4YTkrXc8+Pb2vpKkD5n1eZ/qbcoQ4+Mc11snG7Q 3SpzYmHloN4get1TJPmIkZeGYBa+g8gMAEol3FExeIB9ZXeQN5Lefwq/WJ6i8765tI 5+WEV8rvoFCuw== From: Sasha Levin To: stable@vger.kernel.org, harshit.m.mogalapalli@oracle.com Cc: 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 , linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org Subject: FAILED: Patch "ima: verify the previous kernel's IMA buffer lies in addressable RAM" failed to apply to 5.15-stable tree Date: Sat, 28 Feb 2026 20:52:07 -0500 Message-ID: <20260301015208.1718603-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Hint: ignore X-stable: review Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From 10d1c75ed4382a8e79874379caa2ead8952734f9 Mon Sep 17 00:00:00 2001 From: Harshit Mogalapalli Date: Tue, 30 Dec 2025 22:16:07 -0800 Subject: [PATCH] ima: verify the previous kernel's IMA buffer lies in addressable RAM 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 --- 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 8e29cb4e6a01d..abf8923f8fc51 100644 --- a/include/linux/ima.h +++ b/include/linux/ima.h @@ -69,6 +69,7 @@ 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 5beb69edd12fd..36a34c54de58b 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 #include #include "ima.h" @@ -294,3 +296,36 @@ 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; +} -- 2.51.0