[to-be-updated] x86-kexec-add-a-sanity-check-on-previous-kernels-ima-kexec-buffer.patch removed from -mm tree

[to-be-updated] x86-kexec-add-a-sanity-check-on-previous-kernels-ima-kexec-buffer.patch removed from -mm tree

[Andrew Morton]

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The quilt patch titled
     Subject: x86/kexec: add a sanity check on previous kernel's ima kexec buffer
has been removed from the -mm tree.  Its filename was
     x86-kexec-add-a-sanity-check-on-previous-kernels-ima-kexec-buffer.patch

This patch was dropped because an updated version will be issued

------------------------------------------------------
From: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Subject: x86/kexec: add a sanity check on previous kernel's ima kexec buffer
Date: Wed, 12 Nov 2025 11:30:02 -0800

When the second-stage kernel is booted via kexec with a limiting command
line such as "mem=<size>", the physical range that contains the carried
over IMA measurement list may fall outside the truncated RAM leading to a
kernel panic.

    BUG: unable to handle page fault for address: ffff97793ff47000
    RIP: ima_restore_measurement_list+0xdc/0x45a
    #PF: error_code(0x0000) – not-present page

Other architectures already validate the range with page_is_ram(), as done
in commit: cbf9c4b9617b ("of: check previous kernel's ima-kexec-buffer
against memory bounds") do a similar check on x86.

[akpm@linux-foundation.org: fix comment typo]
Link: https://lkml.kernel.org/r/20251112193005.3772542-1-harshit.m.mogalapalli@oracle.com
Fixes: b69a2afd5afc ("x86/kexec: Carry forward IMA measurement log on kexec")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reported-by: Paul Webb <paul.x.webb@oracle.com>
Reviewed-by: Jonathan McDowell <noodles@meta.com>
Tested-by: Mimi Zohar <zohar@linux.ibm.com>
Cc: Alexander Graf <graf@amazon.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: guoweikang <guoweikang.kernel@gmail.com>
Cc: Henry Willard <henry.willard@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Bohac <jbohac@suse.cz>
Cc: Joel Granados <joel.granados@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Sohil Mehta <sohil.mehta@intel.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Yifei Liu <yifei.l.liu@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/x86/kernel/setup.c |   14 ++++++++++++++
 1 file changed, 14 insertions(+)

--- a/arch/x86/kernel/setup.c~x86-kexec-add-a-sanity-check-on-previous-kernels-ima-kexec-buffer
+++ a/arch/x86/kernel/setup.c
@@ -439,9 +439,23 @@ int __init ima_free_kexec_buffer(void)
 
 int __init ima_get_kexec_buffer(void **addr, size_t *size)
 {
+	unsigned long start_pfn, end_pfn;
+
 	if (!ima_kexec_buffer_size)
 		return -ENOENT;
 
+	/*
+	 * Calculate the PFNs for the buffer and ensure
+	 * they are within addressable memory.
+	 */
+	start_pfn = PFN_DOWN(ima_kexec_buffer_phys);
+	end_pfn = PFN_DOWN(ima_kexec_buffer_phys + ima_kexec_buffer_size - 1);
+	if (!pfn_range_is_mapped(start_pfn, end_pfn)) {
+		pr_warn("IMA buffer at 0x%llx, size = 0x%zx beyond memory\n",
+			ima_kexec_buffer_phys, ima_kexec_buffer_size);
+		return -EINVAL;
+	}
+
 	*addr = __va(ima_kexec_buffer_phys);
 	*size = ima_kexec_buffer_size;
 
_

Patches currently in -mm which might be from harshit.m.mogalapalli@oracle.com are