The patch titled Subject: kexec/arm64: initialize the random field of kbuf to zero in the image loader has been added to the -mm mm-hotfixes-unstable branch. Its filename is kexec-arm64-initialize-the-random-field-of-kbuf-to-zero-in-the-image-loader.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

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: Breno Leitao leitao@debian.org Subject: kexec/arm64: initialize the random field of kbuf to zero in the image loader Date: Thu Aug 21 04:11:21 2025 -0700

Add an explicit initialization for the random member of the kbuf structure within the image_load function in arch/arm64/kernel/kexec_image.c. Setting kbuf.random to zero ensures a deterministic and clean starting state for the buffer used during kernel image loading, avoiding this UBSAN issue later, when kbuf.random is read.

[ 32.362488] UBSAN: invalid-load in ./include/linux/kexec.h:210:10 [ 32.362649] load of value 252 is not a valid value for type '_Bool'

Link: https://lkml.kernel.org/r/oninomspajhxp4omtdapxnckxydbk2nzmrix7rggmpukpnzadw... Fixes: bf454ec31add ("kexec_file: allow to place kexec_buf randomly Signed-off-by: Breno Leitao leitao@debian.org Cc: Baoquan He bhe@redhat.com Cc: Coiby Xu coxu@redhat.com Cc: "Daniel P. Berrange" berrange@redhat.com Cc: Dave Hansen dave.hansen@intel.com Cc: Dave Young dyoung@redhat.com Cc: Kairui Song ryncsn@gmail.com Cc: Liu Pingfan kernelfans@gmail.com Cc: Milan Broz gmazyland@gmail.com Cc: Ondrej Kozina okozina@redhat.com Cc: Vitaly Kuznetsov vkuznets@redhat.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

arch/arm64/kernel/kexec_image.c | 1 + 1 file changed, 1 insertion(+)

--- a/arch/arm64/kernel/kexec_image.c~kexec-arm64-initialize-the-random-field-of-kbuf-to-zero-in-the-image-loader +++ a/arch/arm64/kernel/kexec_image.c @@ -76,6 +76,7 @@ static void *image_load(struct kimage *i kbuf.buf_min = 0; kbuf.buf_max = ULONG_MAX; kbuf.top_down = false; + kbuf.random = 0;

kbuf.buffer = kernel; kbuf.bufsz = kernel_len; _

Patches currently in -mm which might be from leitao@debian.org are

kexec-arm64-initialize-the-random-field-of-kbuf-to-zero-in-the-image-loader.patch