linux-stable/arch/x86/include/asm/microcode.h
Kees Cook 1d8c928ed7 x86/microcode/AMD: Track patch allocation size explicitly
[ Upstream commit 712f210a45 ]

In preparation for reducing the use of ksize(), record the actual
allocation size for later memcpy(). This avoids copying extra
(uninitialized!) bytes into the patch buffer when the requested
allocation size isn't exactly the size of a kmalloc bucket.
Additionally, fix potential future issues where runtime bounds checking
will notice that the buffer was allocated to a smaller value than
returned by ksize().

Fixes: 757885e94a ("x86, microcode, amd: Early microcode patch loading support for AMD")
Suggested-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/lkml/CA+DvKQ+bp7Y7gmaVhacjv9uF6Ar-o4tet872h4Q8RPYPJjcJQA@mail.gmail.com/
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:22:24 +02:00

148 lines
3.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_MICROCODE_H
#define _ASM_X86_MICROCODE_H
#include <asm/cpu.h>
#include <linux/earlycpio.h>
#include <linux/initrd.h>
struct ucode_patch {
struct list_head plist;
void *data; /* Intel uses only this one */
unsigned int size;
u32 patch_id;
u16 equiv_cpu;
};
extern struct list_head microcode_cache;
struct cpu_signature {
unsigned int sig;
unsigned int pf;
unsigned int rev;
};
struct device;
enum ucode_state {
UCODE_OK = 0,
UCODE_NEW,
UCODE_UPDATED,
UCODE_NFOUND,
UCODE_ERROR,
};
struct microcode_ops {
enum ucode_state (*request_microcode_user) (int cpu,
const void __user *buf, size_t size);
enum ucode_state (*request_microcode_fw) (int cpu, struct device *,
bool refresh_fw);
void (*microcode_fini_cpu) (int cpu);
/*
* The generic 'microcode_core' part guarantees that
* the callbacks below run on a target cpu when they
* are being called.
* See also the "Synchronization" section in microcode_core.c.
*/
enum ucode_state (*apply_microcode) (int cpu);
int (*collect_cpu_info) (int cpu, struct cpu_signature *csig);
};
struct ucode_cpu_info {
struct cpu_signature cpu_sig;
int valid;
void *mc;
};
extern struct ucode_cpu_info ucode_cpu_info[];
struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa);
#ifdef CONFIG_MICROCODE_INTEL
extern struct microcode_ops * __init init_intel_microcode(void);
#else
static inline struct microcode_ops * __init init_intel_microcode(void)
{
return NULL;
}
#endif /* CONFIG_MICROCODE_INTEL */
#ifdef CONFIG_MICROCODE_AMD
extern struct microcode_ops * __init init_amd_microcode(void);
extern void __exit exit_amd_microcode(void);
#else
static inline struct microcode_ops * __init init_amd_microcode(void)
{
return NULL;
}
static inline void __exit exit_amd_microcode(void) {}
#endif
#define MAX_UCODE_COUNT 128
#define QCHAR(a, b, c, d) ((a) + ((b) << 8) + ((c) << 16) + ((d) << 24))
#define CPUID_INTEL1 QCHAR('G', 'e', 'n', 'u')
#define CPUID_INTEL2 QCHAR('i', 'n', 'e', 'I')
#define CPUID_INTEL3 QCHAR('n', 't', 'e', 'l')
#define CPUID_AMD1 QCHAR('A', 'u', 't', 'h')
#define CPUID_AMD2 QCHAR('e', 'n', 't', 'i')
#define CPUID_AMD3 QCHAR('c', 'A', 'M', 'D')
#define CPUID_IS(a, b, c, ebx, ecx, edx) \
(!((ebx ^ (a))|(edx ^ (b))|(ecx ^ (c))))
/*
* In early loading microcode phase on BSP, boot_cpu_data is not set up yet.
* x86_cpuid_vendor() gets vendor id for BSP.
*
* In 32 bit AP case, accessing boot_cpu_data needs linear address. To simplify
* coding, we still use x86_cpuid_vendor() to get vendor id for AP.
*
* x86_cpuid_vendor() gets vendor information directly from CPUID.
*/
static inline int x86_cpuid_vendor(void)
{
u32 eax = 0x00000000;
u32 ebx, ecx = 0, edx;
native_cpuid(&eax, &ebx, &ecx, &edx);
if (CPUID_IS(CPUID_INTEL1, CPUID_INTEL2, CPUID_INTEL3, ebx, ecx, edx))
return X86_VENDOR_INTEL;
if (CPUID_IS(CPUID_AMD1, CPUID_AMD2, CPUID_AMD3, ebx, ecx, edx))
return X86_VENDOR_AMD;
return X86_VENDOR_UNKNOWN;
}
static inline unsigned int x86_cpuid_family(void)
{
u32 eax = 0x00000001;
u32 ebx, ecx = 0, edx;
native_cpuid(&eax, &ebx, &ecx, &edx);
return x86_family(eax);
}
#ifdef CONFIG_MICROCODE
int __init microcode_init(void);
extern void __init load_ucode_bsp(void);
extern void load_ucode_ap(void);
void reload_early_microcode(void);
extern bool get_builtin_firmware(struct cpio_data *cd, const char *name);
extern bool initrd_gone;
void microcode_bsp_resume(void);
#else
static inline int __init microcode_init(void) { return 0; };
static inline void __init load_ucode_bsp(void) { }
static inline void load_ucode_ap(void) { }
static inline void reload_early_microcode(void) { }
static inline void microcode_bsp_resume(void) { }
static inline bool
get_builtin_firmware(struct cpio_data *cd, const char *name) { return false; }
#endif
#endif /* _ASM_X86_MICROCODE_H */