[PATCH V8 3/3] Call ima_kexec_cmdline to measure the cmdline args

From: Prakhar Srivastava
Date: Thu Jun 13 2019 - 13:16:25 EST


During soft reboot(kexec_file_load) boot cmdline args
are not measured.Thus the new kernel on load boots with
an assumption of cold reboot.

This patch makes a call to the ima hook ima_kexec_cmdline,
added in "Define a new IMA hook to measure the boot command
line arguments"
to measure the boot cmdline args into the ima log.

- call ima_kexec_cmdline from kexec_file_load.
- move the call ima_add_kexec_buffer after the cmdline
args have been measured.

Signed-off-by: Prakhar Srivastava <prsriva02@xxxxxxxxx>
---
kernel/kexec_file.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 072b6ee55e3f..b0c724e5d86c 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -198,9 +198,6 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
return ret;
image->kernel_buf_len = size;

- /* IMA needs to pass the measurement list to the next kernel. */
- ima_add_kexec_buffer(image);
-
/* Call arch image probe handlers */
ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
image->kernel_buf_len);
@@ -241,8 +238,14 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
ret = -EINVAL;
goto out;
}
+
+ ima_kexec_cmdline(image->cmdline_buf,
+ image->cmdline_buf_len - 1);
}

+ /* IMA needs to pass the measurement list to the next kernel. */
+ ima_add_kexec_buffer(image);
+
/* Call arch image load handlers */
ldata = arch_kexec_kernel_image_load(image);

--
2.19.1