m68k: Rework BI_VIRT_RNG_SEED as BI_RNG_SEED

This is useful on !virt platforms for kexec, so change things from
BI_VIRT_RNG_SEED to be BI_RNG_SEED, and simply remove BI_VIRT_RNG_SEED
because it only ever lasted one release, and nothing is broken by not
having it. At the same time, keep a comment noting that it's been
removed, so that ID isn't reused. In addition, we previously documented
2-byte alignment, but 4-byte alignment is actually necessary, so update
that comment.

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: a1ee38ab1a ("m68k: virt: Use RNG seed from bootinfo block")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20220927130835.1629806-2-Jason@zx2c4.com
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
This commit is contained in:
Jason A. Donenfeld 2022-09-27 15:08:35 +02:00 committed by Geert Uytterhoeven
parent 7c236d93c6
commit dc63a086da
4 changed files with 21 additions and 18 deletions

View File

@ -13,13 +13,8 @@
#define BI_VIRT_VIRTIO_BASE 0x8004
#define BI_VIRT_CTRL_BASE 0x8005
/*
* A random seed used to initialize the RNG. Record format:
*
* - length [ 2 bytes, 16-bit big endian ]
* - seed data [ `length` bytes, padded to preserve 2-byte alignment ]
*/
#define BI_VIRT_RNG_SEED 0x8006
/* No longer used -- replaced with BI_RNG_SEED -- but don't reuse this index:
* #define BI_VIRT_RNG_SEED 0x8006 */
#define VIRT_BOOTI_VERSION MK_BI_VERSION(2, 0)

View File

@ -64,6 +64,13 @@ struct mem_info {
/* (struct mem_info) */
#define BI_COMMAND_LINE 0x0007 /* kernel command line parameters */
/* (string) */
/*
* A random seed used to initialize the RNG. Record format:
*
* - length [ 2 bytes, 16-bit big endian ]
* - seed data [ `length` bytes, padded to preserve 4-byte struct alignment ]
*/
#define BI_RNG_SEED 0x0008
/*

View File

@ -25,6 +25,7 @@
#include <linux/module.h>
#include <linux/nvram.h>
#include <linux/initrd.h>
#include <linux/random.h>
#include <asm/bootinfo.h>
#include <asm/byteorder.h>
@ -151,6 +152,17 @@ static void __init m68k_parse_bootinfo(const struct bi_record *record)
sizeof(m68k_command_line));
break;
case BI_RNG_SEED: {
u16 len = be16_to_cpup(data);
add_bootloader_randomness(data + 2, len);
/*
* Zero the data to preserve forward secrecy, and zero the
* length to prevent kexec from using it.
*/
memzero_explicit((void *)data, len + 2);
break;
}
default:
if (MACH_IS_AMIGA)
unknown = amiga_parse_bootinfo(record);

View File

@ -2,7 +2,6 @@
#include <linux/reboot.h>
#include <linux/serial_core.h>
#include <linux/random.h>
#include <clocksource/timer-goldfish.h>
#include <asm/bootinfo.h>
@ -93,16 +92,6 @@ int __init virt_parse_bootinfo(const struct bi_record *record)
data += 4;
virt_bi_data.virtio.irq = be32_to_cpup(data);
break;
case BI_VIRT_RNG_SEED: {
u16 len = be16_to_cpup(data);
add_bootloader_randomness(data + 2, len);
/*
* Zero the data to preserve forward secrecy, and zero the
* length to prevent kexec from using it.
*/
memzero_explicit((void *)data, len + 2);
break;
}
default:
unknown = 1;
break;