Fix the VTOY_LINUX_REMOUNT option for new linux kernel in intel 11th(and later) gen CPU.

This commit is contained in:
longpanda 2023-03-26 10:45:19 +08:00
parent e743f7c15f
commit b32eda4262
12 changed files with 277 additions and 9 deletions

View file

@ -52,7 +52,8 @@ typedef struct ko_param
unsigned long sym_put_addr;
unsigned long sym_put_size;
unsigned long kv_major;
unsigned long padding[2];
unsigned long ibt;
unsigned long padding[1];
}ko_param;
#pragma pack()
@ -91,6 +92,52 @@ static volatile ko_param g_ko_param =
#error "unsupported arch"
#endif
#ifdef VTOY_IBT
#ifdef CONFIG_X86_64
/* Using 64-bit values saves one instruction clearing the high half of low */
#define DECLARE_ARGS(val, low, high) unsigned long low, high
#define EAX_EDX_VAL(val, low, high) ((low) | (high) << 32)
#define EAX_EDX_RET(val, low, high) "=a" (low), "=d" (high)
#else
#define DECLARE_ARGS(val, low, high) unsigned long long val
#define EAX_EDX_VAL(val, low, high) (val)
#define EAX_EDX_RET(val, low, high) "=A" (val)
#endif
#define EX_TYPE_WRMSR 8
#define EX_TYPE_RDMSR 9
#define MSR_IA32_S_CET 0x000006a2 /* kernel mode cet */
#define CET_ENDBR_EN (1ULL << 2)
/* Exception table entry */
#ifdef __ASSEMBLY__
#define _ASM_EXTABLE_TYPE(from, to, type) \
.pushsection "__ex_table","a" ; \
.balign 4 ; \
.long (from) - . ; \
.long (to) - . ; \
.long type ; \
.popsection
#else /* ! __ASSEMBLY__ */
#define _ASM_EXTABLE_TYPE(from, to, type) \
" .pushsection \"__ex_table\",\"a\"\n" \
" .balign 4\n" \
" .long (" #from ") - .\n" \
" .long (" #to ") - .\n" \
" .long " __stringify(type) " \n" \
" .popsection\n"
#endif /* __ASSEMBLY__ */
#endif /* VTOY_IBT */
#define vdebug(fmt, args...) if(kprintf) kprintf(KERN_ERR fmt, ##args)
static unsigned char *g_get_patch[MAX_PATCH] = { NULL };
@ -166,11 +213,66 @@ static int notrace dmpatch_replace_code
return 0;
}
#ifdef VTOY_IBT
static __always_inline unsigned long long dmpatch_rdmsr(unsigned int msr)
{
DECLARE_ARGS(val, low, high);
asm volatile("1: rdmsr\n"
"2:\n"
_ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_RDMSR)
: EAX_EDX_RET(val, low, high) : "c" (msr));
return EAX_EDX_VAL(val, low, high);
}
static __always_inline void dmpatch_wrmsr(unsigned int msr, u32 low, u32 high)
{
asm volatile("1: wrmsr\n"
"2:\n"
_ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_WRMSR)
: : "c" (msr), "a"(low), "d" (high) : "memory");
}
static u64 dmpatch_ibt_save(void)
{
u64 msr = 0;
u64 val = 0;
msr = dmpatch_rdmsr(MSR_IA32_S_CET);
val = msr & ~CET_ENDBR_EN;
dmpatch_wrmsr(MSR_IA32_S_CET, (u32)(val & 0xffffffffULL), (u32)(val >> 32));
return msr;
}
static void dmpatch_ibt_restore(u64 save)
{
u64 msr;
msr = dmpatch_rdmsr(MSR_IA32_S_CET);
msr &= ~CET_ENDBR_EN;
msr |= (save & CET_ENDBR_EN);
dmpatch_wrmsr(MSR_IA32_S_CET, (u32)(msr & 0xffffffffULL), (u32)(msr >> 32));
}
#else
static u64 dmpatch_ibt_save(void) { return 0; }
static void dmpatch_ibt_restore(u64 save) { (void)save; }
#endif
static int notrace dmpatch_init(void)
{
int r = 0;
int rc = 0;
u64 msr = 0;
if (g_ko_param.ibt == 0x8888)
{
msr = dmpatch_ibt_save();
}
kprintf = (printk_pf)(g_ko_param.printk_addr);
vdebug("dmpatch_init start pagesize=%lu ...\n", g_ko_param.pgsize);
@ -218,6 +320,11 @@ static int notrace dmpatch_init(void)
vdebug("######## dm patch success ###########\n");
vdebug("#####################################\n");
if (g_ko_param.ibt == 0x8888)
{
dmpatch_ibt_restore(msr);
}
out:
return rc;
@ -226,6 +333,12 @@ out:
static void notrace dmpatch_exit(void)
{
int i = 0;
u64 msr;
if (g_ko_param.ibt == 0x8888)
{
msr = dmpatch_ibt_save();
}
for (i = 0; i < MAX_PATCH; i++)
{
@ -234,6 +347,11 @@ static void notrace dmpatch_exit(void)
}
vdebug("dmpatch_exit success\n");
if (g_ko_param.ibt == 0x8888)
{
dmpatch_ibt_restore(msr);
}
}
module_init(dmpatch_init);