[PATCH v6 07/14] LoongArch: kexec_file: Fix elf_headers memory leak in retry loop

[Jinjie Ruan <ruanjinjie@huawei.com>]

If load_other_segments() fails after image->elf_headers is assigned,
the memory lifecycle is safely managed by the global kimage object
and will be freed in arch_kimage_file_post_load_cleanup().

However, during a retry loop in efi_kexec_load(), a subsequent iteration
will allocate a new buffer and overwrite image->elf_headers. This
permanently leaks the stale memory from the previous iteration before
the global cleanup can track it.

Fix this by explicitly freeing the stale `image->elf_headers` buffer
before assigning the newly allocated headers.

Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Youling Tang <tangyouling@kylinos.cn>
Cc: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
Cc: Sourabh Jain <sourabhjain@linux.ibm.com>
Cc: Kees Cook <kees@kernel.org>
Cc: stable@vger.kernel.org
Link: https://sashiko.dev/#/patchset/20260729031235.2840255-1-ruanjinjie%40huawei.com
Fixes: 55d990f0084c ("LoongArch: Add EFI binary support for kexec_file")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
---
 arch/loongarch/kernel/machine_kexec_file.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/loongarch/kernel/machine_kexec_file.c b/arch/loongarch/kernel/machine_kexec_file.c
index 62a5be102065..3beb6977ecc6 100644
--- a/arch/loongarch/kernel/machine_kexec_file.c
+++ b/arch/loongarch/kernel/machine_kexec_file.c
@@ -166,6 +166,10 @@ int load_other_segments(struct kimage *image,
 			vfree(headers);
 			goto out_err;
 		}
+
+		if (unlikely(image->elf_headers))
+			vfree(image->elf_headers);
+
 		image->elf_headers = headers;
 		image->elf_load_addr = kbuf.mem;
 		image->elf_headers_sz = headers_sz;
-- 
2.34.1