qemu/hw/i386/e820_memory_layout.h
David Woodhouse 93c76555d8 hw/i386/fw_cfg: Add etc/e820 to fw_cfg late
In e820_add_entry() the e820_table is reallocated with g_renew() to make
space for a new entry. However, fw_cfg_arch_create() just uses the
existing e820_table pointer. This leads to a use-after-free if anything
adds a new entry after fw_cfg is set up.

Shift the addition of the etc/e820 file to the machine done notifier, via
a new fw_cfg_add_e820() function.

Also make e820_table private and use an e820_get_table() accessor function
for it, which sets a flag that will trigger an assert() for any *later*
attempts to add to the table.

Make e820_add_entry() return void, as most callers don't check for error
anyway.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <a2708734f004b224f33d3b4824e9a5a262431568.camel@infradead.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2024-07-03 18:14:06 -04:00

31 lines
697 B
C

/*
* QEMU BIOS e820 routines
*
* Copyright (c) 2003-2004 Fabrice Bellard
*
* SPDX-License-Identifier: MIT
*/
#ifndef HW_I386_E820_MEMORY_LAYOUT_H
#define HW_I386_E820_MEMORY_LAYOUT_H
/* e820 types */
#define E820_RAM 1
#define E820_RESERVED 2
#define E820_ACPI 3
#define E820_NVS 4
#define E820_UNUSABLE 5
struct e820_entry {
uint64_t address;
uint64_t length;
uint32_t type;
} QEMU_PACKED __attribute((__aligned__(4)));
void e820_add_entry(uint64_t address, uint64_t length, uint32_t type);
bool e820_get_entry(int index, uint32_t type,
uint64_t *address, uint64_t *length);
int e820_get_table(struct e820_entry **table);
#endif