+ crash_dump-dont-log-dm-crypt-key-bytes-in-read_key_from_user_keying.patch added to mm-hotfixes-unstable branch

+ crash_dump-dont-log-dm-crypt-key-bytes-in-read_key_from_user_keying.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: crash_dump: don't log dm-crypt key bytes in read_key_from_user_keying
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     crash_dump-dont-log-dm-crypt-key-bytes-in-read_key_from_user_keying.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/crash_dump-dont-log-dm-crypt-key-bytes-in-read_key_from_user_keying.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: Thorsten Blum <thorsten.blum@linux.dev>
Subject: crash_dump: don't log dm-crypt key bytes in read_key_from_user_keying
Date: Sat, 28 Feb 2026 00:00:09 +0100

When debug logging is enabled, read_key_from_user_keying() logs the first
8 bytes of the key payload and partially exposes the dm-crypt key.  Stop
logging any key bytes.

Link: https://lkml.kernel.org/r/20260227230008.858641-2-thorsten.blum@linux.dev
Fixes: 479e58549b0f ("crash_dump: store dm crypt keys in kdump reserved memory")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Cc: Baoquan He <bhe@redhat.com>
Cc: Coiby Xu <coxu@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/crash_dump_dm_crypt.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/crash_dump_dm_crypt.c~crash_dump-dont-log-dm-crypt-key-bytes-in-read_key_from_user_keying
+++ a/kernel/crash_dump_dm_crypt.c
@@ -168,8 +168,8 @@ static int read_key_from_user_keying(str
 
 	memcpy(dm_key->data, ukp->data, ukp->datalen);
 	dm_key->key_size = ukp->datalen;
-	kexec_dprintk("Get dm crypt key (size=%u) %s: %8ph\n", dm_key->key_size,
-		      dm_key->key_desc, dm_key->data);
+	kexec_dprintk("Get dm crypt key (size=%u) %s\n", dm_key->key_size,
+		      dm_key->key_desc);
 
 out:
 	up_read(&key->sem);
_

Patches currently in -mm which might be from thorsten.blum@linux.dev are

crash_dump-dont-log-dm-crypt-key-bytes-in-read_key_from_user_keying.patch
fork-replace-simple_strtoul-with-kstrtoul-in-coredump_filter_setup.patch
crash_dump-remove-redundant-less-than-zero-check.patch