+ kexec_file-fix-elfcorehdr-digest-exclusion-when-config_crash_hotplug=y.patch added to mm-hotfixes-unstable branch

+ kexec_file-fix-elfcorehdr-digest-exclusion-when-config_crash_hotplug=y.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: kexec_file: fix elfcorehdr digest exclusion when CONFIG_CRASH_HOTPLUG=y
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     kexec_file-fix-elfcorehdr-digest-exclusion-when-config_crash_hotplug=y.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kexec_file-fix-elfcorehdr-digest-exclusion-when-config_crash_hotplug=y.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Petr Tesarik <ptesarik@suse.com>
Subject: kexec_file: fix elfcorehdr digest exclusion when CONFIG_CRASH_HOTPLUG=y
Date: Mon, 5 Aug 2024 17:07:50 +0200

Fix the condition to exclude the elfcorehdr segment from the SHA digest
calculation.

The j iterator is an index into the output sha_regions[] array, not into
the input image->segment[] array.  Once it reaches
image->elfcorehdr_index, all subsequent segments are excluded.  Besides,
if the purgatory segment precedes the elfcorehdr segment, the elfcorehdr
may be wrongly included in the calculation.

Link: https://lkml.kernel.org/r/20240805150750.170739-1-petr.tesarik@suse.com
Fixes: f7cc804a9fd4 ("kexec: exclude elfcorehdr from the segment digest")
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Cc: Eric DeVolder <eric_devolder@yahoo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/kexec_file.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/kexec_file.c~kexec_file-fix-elfcorehdr-digest-exclusion-when-config_crash_hotplug=y
+++ a/kernel/kexec_file.c
@@ -752,7 +752,7 @@ static int kexec_calculate_store_digests
 
 #ifdef CONFIG_CRASH_HOTPLUG
 		/* Exclude elfcorehdr segment to allow future changes via hotplug */
-		if (j == image->elfcorehdr_index)
+		if (i == image->elfcorehdr_index)
 			continue;
 #endif
 
_

Patches currently in -mm which might be from ptesarik@suse.com are

kexec_file-fix-elfcorehdr-digest-exclusion-when-config_crash_hotplug=y.patch