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uti: Replace data types represented as arrays with C structures

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Defining C structures for the following objects:
(1) Remote and local context
(2) Stack of system call arguments / return values

Change-Id: Iafbb6c795bd765e3c78c54a255d8a1e4d4536288
This commit is contained in:
Masamichi Takagi
2018-09-03 18:20:00 +09:00
parent 04d4145b3e
commit 781a69617b
12 changed files with 215 additions and 188 deletions
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63
executer/user/syscall_intercept.c
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@@ -24,6 +24,7 @@ hook(long syscall_number,
int tid = uti_syscall0(__NR_gettid);
struct terminate_thread_desc term_desc;
unsigned long code;
int stack_top;
if (!uti_desc.start_syscall_intercept) {
return 1; /* System call isn't taken over */
@@ -50,34 +51,40 @@ hook(long syscall_number,
case __NR_munmap:
case __NR_mprotect:
case __NR_mremap:
if (!uti_desc.syscall_param_top) {
/* Overflow check */
if (uti_desc.syscall_stack_top == -1) {
*result = -ENOMEM;
return 0;
}
else {
/* Pop syscall_struct list for reentrant safety */
uti_desc.syscall_param = uti_desc.syscall_param_top;
uti_desc.syscall_param_top = *(void **)uti_desc.syscall_param;
uti_desc.syscall_param->number = syscall_number;
uti_desc.syscall_param->args[0] = arg0;
uti_desc.syscall_param->args[1] = arg1;
uti_desc.syscall_param->args[2] = arg2;
uti_desc.syscall_param->args[3] = arg3;
uti_desc.syscall_param->args[4] = arg4;
uti_desc.syscall_param->args[5] = arg5;
uti_desc.syscall_param->uti_clv = uti_desc.uti_clv;
uti_desc.syscall_param->ret = -EINVAL;
uti_syscall3(__NR_ioctl, uti_desc.fd, MCEXEC_UP_SYSCALL_THREAD, (long)uti_desc.syscall_param);
*result = uti_desc.syscall_param->ret;
/* push syscall_struct list */
*(void **)uti_desc.syscall_param = uti_desc.syscall_param_top;
uti_desc.syscall_param_top = uti_desc.syscall_param;
return 0; /* System call is taken over */
/* Sanity check */
if (uti_desc.syscall_stack_top < 0 || uti_desc.syscall_stack_top >= UTI_SZ_SYSCALL_STACK) {
*result = -EINVAL;
return 0;
}
break;
/* Store the return value in the stack to prevent it from getting corrupted
when an interrupt happens just after ioctl() and before copying the return
value to *result */
stack_top = __sync_fetch_and_sub(&uti_desc.syscall_stack_top, 1);
uti_desc.syscall_stack[stack_top].number = syscall_number;
uti_desc.syscall_stack[stack_top].args[0] = arg0;
uti_desc.syscall_stack[stack_top].args[1] = arg1;
uti_desc.syscall_stack[stack_top].args[2] = arg2;
uti_desc.syscall_stack[stack_top].args[3] = arg3;
uti_desc.syscall_stack[stack_top].args[4] = arg4;
uti_desc.syscall_stack[stack_top].args[5] = arg5;
uti_desc.syscall_stack[stack_top].uti_clv = uti_desc.uti_clv;
uti_desc.syscall_stack[stack_top].ret = -EINVAL;
uti_syscall3(__NR_ioctl, uti_desc.fd, MCEXEC_UP_SYSCALL_THREAD, (long)(uti_desc.syscall_stack + stack_top));
*result = uti_desc.syscall_stack[stack_top].ret;
/* push syscall_struct list */
__sync_fetch_and_add(&uti_desc.syscall_stack_top, 1);
return 0; /* System call is taken over */
case __NR_exit_group:
code = 0x100000000;
goto make_remote_thread_exit;
@@ -116,9 +123,13 @@ hook(long syscall_number,
static __attribute__((constructor)) void
init(void)
{
// Set up the callback function
/* Set up the callback function */
intercept_hook_point = hook;
/* Initialize uti_desc */
uti_desc.syscall_stack_top = UTI_SZ_SYSCALL_STACK - 1;
/* Pass address of uti_desc to McKernel */
uti_syscall1(733, (unsigned long)&uti_desc);
}