[PATCH 5.15 12/14] kexec: clean up arch_kexec_kernel_verify_sig

Greg Kroah-Hartman
2022-08-19T15:42:02Z

From: Coiby Xu <coxu@redhat.com>

commit 689a71493bd2f31c024f8c0395f85a1fd4b2138e upstream.

Before commit 105e10e2cf1c ("kexec_file: drop weak attribute from
functions"), there was already no arch-specific implementation
of arch_kexec_kernel_verify_sig. With weak attribute dropped by that
commit, arch_kexec_kernel_verify_sig is completely useless. So clean it
up.

Note later patches are dependent on this patch so it should be backported
to the stable tree as well.

Cc: stable@vger.kernel.org
Suggested-by: Eric W. Biederman <ebiederm@xmission.com>
Reviewed-by: Michal Suchanek <msuchanek@suse.de>
Acked-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Coiby Xu <coxu@redhat.com>
[zohar@linux.ibm.com: reworded patch description "Note"]
Link: https://lore.kernel.org/linux-integrity/20220714134027.394370-1-coxu@redhat.com/
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/linux/kexec.h | 5 -----
kernel/kexec_file.c | 33 +++++++++++++--------------------
2 files changed, 13 insertions(+), 25 deletions(-)

--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -206,11 +206,6 @@ static inline void *arch_kexec_kernel_im
}
#endif

-#ifdef CONFIG_KEXEC_SIG
-int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
- unsigned long buf_len);
-#endif
-
extern int kexec_add_buffer(struct kexec_buf *kbuf);
int kexec_locate_mem_hole(struct kexec_buf *kbuf);

--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -81,24 +81,6 @@ int kexec_image_post_load_cleanup_defaul
return image->fops->cleanup(image->image_loader_data);
}

-#ifdef CONFIG_KEXEC_SIG
-static int kexec_image_verify_sig_default(struct kimage *image, void *buf,
- unsigned long buf_len)
-{
- if (!image->fops || !image->fops->verify_sig) {
- pr_debug("kernel loader does not support signature verification.\n");
- return -EKEYREJECTED;
- }
-
- return image->fops->verify_sig(buf, buf_len);
-}
-
-int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, unsigned long buf_len)
-{
- return kexec_image_verify_sig_default(image, buf, buf_len);
-}
-#endif
-
/*
* Free up memory used by kernel, initrd, and command line. This is temporary
* memory allocation which is not needed any more after these buffers have
@@ -141,13 +123,24 @@ void kimage_file_post_load_cleanup(struc
}

#ifdef CONFIG_KEXEC_SIG
+static int kexec_image_verify_sig(struct kimage *image, void *buf,
+ unsigned long buf_len)
+{
+ if (!image->fops || !image->fops->verify_sig) {
+ pr_debug("kernel loader does not support signature verification.\n");
+ return -EKEYREJECTED;
+ }
+
+ return image->fops->verify_sig(buf, buf_len);
+}
+
static int
kimage_validate_signature(struct kimage *image)
{
int ret;

- ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf,
- image->kernel_buf_len);
+ ret = kexec_image_verify_sig(image, image->kernel_buf,
+ image->kernel_buf_len);
if (ret) {

if (sig_enforce) {