[PATCH 2/3] riscv: kexec: Initialize kexec_buf struct
From: Breno Leitao <leitao@debian.org>
Date: 2025-08-27 10:42:37
Also in:
linux-riscv, linux-s390, lkml
Subsystem:
risc-v architecture, the rest · Maintainers:
Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds
The kexec_buf structure was previously declared without initialization.
commit bf454ec31add ("kexec_file: allow to place kexec_buf randomly")
added a field that is always read but not consistently populated by all
architectures. This un-initialized field will contain garbage.
This is also triggering a UBSAN warning when the uninitialized data was
accessed:
------------[ cut here ]------------
UBSAN: invalid-load in ./include/linux/kexec.h:210:10
load of value 252 is not a valid value for type '_Bool'
Zero-initializing kexec_buf at declaration ensures all fields are
cleanly set, preventing future instances of uninitialized memory being
used.
Fixes: bf454ec31add ("kexec_file: allow to place kexec_buf randomly")
Signed-off-by: Breno Leitao <leitao@debian.org>
---
arch/riscv/kernel/kexec_elf.c | 4 ++--
arch/riscv/kernel/kexec_image.c | 2 +-
arch/riscv/kernel/machine_kexec_file.c | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/riscv/kernel/kexec_elf.c b/arch/riscv/kernel/kexec_elf.c
index 56444c7bd34eb..531d348db84d7 100644
--- a/arch/riscv/kernel/kexec_elf.c
+++ b/arch/riscv/kernel/kexec_elf.c@@ -28,7 +28,7 @@ static int riscv_kexec_elf_load(struct kimage *image, struct elfhdr *ehdr, int i; int ret = 0; size_t size; - struct kexec_buf kbuf; + struct kexec_buf kbuf = {}; const struct elf_phdr *phdr; kbuf.image = image;
@@ -66,7 +66,7 @@ static int elf_find_pbase(struct kimage *image, unsigned long kernel_len, { int i; int ret; - struct kexec_buf kbuf; + struct kexec_buf kbuf = {}; const struct elf_phdr *phdr; unsigned long lowest_paddr = ULONG_MAX; unsigned long lowest_vaddr = ULONG_MAX;
diff --git a/arch/riscv/kernel/kexec_image.c b/arch/riscv/kernel/kexec_image.c
index 26a81774a78a3..8f2eb900910b1 100644
--- a/arch/riscv/kernel/kexec_image.c
+++ b/arch/riscv/kernel/kexec_image.c@@ -41,7 +41,7 @@ static void *image_load(struct kimage *image, struct riscv_image_header *h; u64 flags; bool be_image, be_kernel; - struct kexec_buf kbuf; + struct kexec_buf kbuf = {}; int ret; /* Check Image header */
diff --git a/arch/riscv/kernel/machine_kexec_file.c b/arch/riscv/kernel/machine_kexec_file.c
index e36104af2e247..b9eb41b0a9751 100644
--- a/arch/riscv/kernel/machine_kexec_file.c
+++ b/arch/riscv/kernel/machine_kexec_file.c@@ -261,7 +261,7 @@ int load_extra_segments(struct kimage *image, unsigned long kernel_start, int ret; void *fdt; unsigned long initrd_pbase = 0UL; - struct kexec_buf kbuf; + struct kexec_buf kbuf = {}; char *modified_cmdline = NULL; kbuf.image = image;
--
2.47.3