KEYS: correct alignment of system_certificate_list content in assembly file

Apart from data-type specific alignment constraints, there are also
architecture-specific alignment requirements.
For example, on s390 symbols must be on even addresses implying a 2-byte
alignment.  If the system_certificate_list_end symbol is on an odd address
and if this address is loaded, the least-significant bit is ignored.  As a
result, the load_system_certificate_list() fails to load the certificates
because of a wrong certificate length calculation.

To be safe, align system_certificate_list on an 8-byte boundary.  Also improve
the length calculation of the system_certificate_list content.  Introduce a
system_certificate_list_size (8-byte aligned because of unsigned long) variable
that stores the length.  Let the linker calculate this size by introducing
a start and end label for the certificate content.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 12 insertions, 2 deletions

diff --git a/kernel/system_certificates.S b/kernel/system_certificates.S
index 4aef390671cb..3e9868d47535 100644
--- a/kernel/system_certificates.S
+++ b/kernel/system_certificates.S
@@ -3,8 +3,18 @@
 
         __INITRODATA
 
+        .align 8
         .globl VMLINUX_SYMBOL(system_certificate_list)
 VMLINUX_SYMBOL(system_certificate_list):
+__cert_list_start:
         .incbin "kernel/x509_certificate_list"
-        .globl VMLINUX_SYMBOL(system_certificate_list_end)
-VMLINUX_SYMBOL(system_certificate_list_end):
+__cert_list_end:
+
+        .align 8
+        .globl VMLINUX_SYMBOL(system_certificate_list_size)
+VMLINUX_SYMBOL(system_certificate_list_size):
+#ifdef CONFIG_64BIT
+        .quad __cert_list_end - __cert_list_start
+#else
+        .long __cert_list_end - __cert_list_start
+#endif