bool
copy_from_user(struct mm_struct *mm, void *dst, const void *src, size_t len, bool writable) {
if (!user_mem_check(mm, (uintptr_t)src, len, writable)) {
return 0;
}
memcpy(dst, src, len);
return 1;
}
bool
copy_to_user(struct mm_struct *mm, void *dst, const void *src, size_t len) {
if (!user_mem_check(mm, (uintptr_t)dst, len, 1)) {
return 0;
}
memcpy(dst, src, len);
return 1;
}
//
// Checks that environment 'env' is allowed to access the range
// of memory [va, va+len) with permissions 'perm | PTE_U | PTE_P'.
// If it can, then the function simply returns.
// If it cannot, 'env' is destroyed and, if env is the current
// environment, this function will not return.
//
void
user_mem_assert(struct Env *env, const void *va, size_t len, int perm)
{
if (user_mem_check(env, va, len, perm | PTE_U) < 0) {
cprintf("[%08x] user_mem_check assertion failure for "
"va %08x\n", env->env_id, user_mem_check_addr);
env_destroy(env); // may not return
}
}
int
sys_get_home_dir(char* buf) {
int r;
if(curenv->user == -1)
return -1;
if((r = user_mem_check(curenv, buf, MAX_PATH_LENGTH, PTE_U|PTE_W)) <0) {
cprintf("SYS_get_logged_user_name: %08x\n",r);
return r;
}
memmove(buf,"/home/stam",11);
return 0;
}
int
sys_update_current_path(char* buf) {
int r;
if(curenv->user == -1)
return -1;
if((r = user_mem_check(curenv, buf, MAX_PATH_LENGTH, PTE_U)) <0) {
cprintf("SYS_get_logged_user_name: %08x\n",r);
return r;
}
memmove(users[curenv->user].path,buf,MAX_PATH_LENGTH);
return 0;
}
int
sys_get_logged_user_name(char* buf) {
int r;
if(curenv->user == -1)
return -1;
if((r = user_mem_check(curenv, buf, MAX_USER_LENGTH, PTE_U|PTE_W)) <0) {
cprintf("SYS_get_logged_user_name: %08x\n",r);
return r;
}
memmove(buf,users[curenv->user].user,MAX_USER_LENGTH);
return 0;
}
int ipc_event_recv(int *pid_store, int *event_store, unsigned int timeout)
{
if (event_store == NULL) {
return -E_INVAL;
}
struct mm_struct *mm = current->mm;
if (pid_store != NULL) {
if (!user_mem_check(mm, (uintptr_t) pid_store, sizeof(int), 1)) {
return -E_INVAL;
}
}
if (!user_mem_check(mm, (uintptr_t) event_store, sizeof(int), 1)) {
return -E_INVAL;
}
unsigned long saved_ticks;
timer_t __timer, *timer =
ipc_timer_init(timeout, &saved_ticks, &__timer);
int pid, event, ret;
if ((ret = recv_event(&pid, &event, timer)) == 0) {
lock_mm(mm);
{
ret = -E_INVAL;
if (pid_store == NULL
|| copy_to_user(mm, pid_store, &pid, sizeof(int))) {
if (copy_to_user
(mm, event_store, &event, sizeof(int))) {
ret = 0;
}
}
}
unlock_mm(mm);
return ret;
}
return ipc_check_timeout(timeout, saved_ticks);
}
/**
* Read a word from the container process's vm when we are in the main one
* This is only used to 'touch' the page as read so the page table will be right.
* See 'copy_from_user' in arch/um/mm/vmm.c for details.
* @param proc the PCB whose container process will be touched
* @param addr the address of the word to be touched (should be valid in the container process)
* @param data the data to be read (of no use now)
* @return 0 on success, or a negative otherwise
*/
int
host_getvalue (struct proc_struct *proc,
uintptr_t addr, uint32_t* data)
{
if (!user_mem_check(proc->mm, addr, sizeof (uintptr_t), 0)) {
return -1;
}
struct stub_stack *stub_stack = proc->arch.host->stub_stack;
struct stub_frame *frame = current_stub_frame (stub_stack);
frame->eax = 0;
frame->ebx = addr;
int ret = host_syscall_in_child (proc);
if (data != NULL)
*data = ret;
return 0;
}
// Set envid's trap frame to 'tf'.
// tf is modified to make sure that user environments always run at code
// protection level 3 (CPL 3) with interrupts enabled.
//
// Returns 0 on success, < 0 on error. Errors are:
// -E_BAD_ENV if environment envid doesn't currently exist,
// or the caller doesn't have permission to change envid.
static int
sys_env_set_trapframe(envid_t envid, struct Trapframe *tf)
{
// LAB 5: Your code here.
// Remember to check whether the user has supplied us with a good
// address!
struct Env *env;
int r;
if ((r = envid2env(envid, &env, 1)) < 0)
return r; /*-E_BAD_ENV*/
if ((r = user_mem_check(curenv, tf, sizeof(struct Trapframe), PTE_U | PTE_P)) < 0)
return r;
env->env_tf = *tf;
env->env_tf.tf_eflags |= FL_IF;
return 0;
// panic("sys_env_set_trapframe not implemented");
}
/**
* Write a word to the container process's vm when we are in the main one
* This is only used to 'touch' the page as written so the page table will be right.
* See 'copy_to_user' in arch/um/mm/vmm.c for details.
* @param proc the PCB whose container process will be touched
* @param addr the address of the word to be touched (should be valid in the container process)
* @param data the data to be written (of no use now)
* @return 0 on success, or a negative otherwise
*/
int
host_assign (struct proc_struct *proc,
uintptr_t addr, uint32_t data)
{
if (!user_mem_check(proc->mm, addr, sizeof (uintptr_t), 1)) {
kprintf ("try assigning invalid address: 0x%x\n", addr);
return -1;
}
/* Use stub call so that the page table will be modified properly */
struct stub_stack *stub_stack = proc->arch.host->stub_stack;
struct stub_frame *frame = current_stub_frame (stub_stack);
frame->eax = -1;
frame->ebx = addr;
frame->ecx = data;
return host_syscall_in_child (proc);
}
/* sysfile_get cwd - get current working directory */
int
sysfile_getcwd(char *buf, size_t len) {
struct mm_struct *mm = current->mm;
if (len == 0) {
return -E_INVAL;
}
int ret = -E_INVAL;
lock_mm(mm);
{
if (user_mem_check(mm, (uintptr_t)buf, len, 1)) {
struct iobuf __iob, *iob = iobuf_init(&__iob, buf, len, 0);
ret = vfs_getcwd(iob);
}
}
unlock_mm(mm);
return ret;
}
static int
sys_proc_save(envid_t envid, struct proc *ps)
{
struct Env *e;
struct Page *pg;
int offset;
//save env
if (envid2env(envid, &e, 1) <0)
return -E_BAD_ENV;
if (user_mem_check(curenv, ps, sizeof(struct proc), PTE_U|PTE_W|PTE_P) <0)
return -E_FAULT;
ps->env = *e;
//save stack
if ((pg=page_lookup(e->env_pgdir, (void *)(USTACKTOP-PGSIZE), NULL))==NULL)
return -E_FAULT;
memmove(ps->stack, page2kva(pg), PGSIZE);
// cprintf("process %x has been saved\n", envid);
return 0;
}
int
sysfile_pipe(int *fd_store) {
struct mm_struct *mm = current->mm;
int ret, fd[2];
if (!user_mem_check(mm, (uintptr_t)fd_store, sizeof(fd), 1)) {
return -E_INVAL;
}
if ((ret = file_pipe(fd)) == 0) {
lock_mm(mm);
{
if (!copy_to_user(mm, fd_store, fd, sizeof(fd))) {
ret = -E_INVAL;
}
}
unlock_mm(mm);
if (ret != 0) {
file_close(fd[0]), file_close(fd[1]);
}
}
return ret;
}
//restore one process
static int
sys_proc_resume(envid_t envid, struct proc *ps)
{
struct Env *e;
struct Page *pg;
int offset;
if (envid2env(envid, &e, 1) <0)
return -E_BAD_ENV;
if (user_mem_check(curenv, ps, sizeof(struct proc), PTE_U|PTE_P) <0)
return -E_FAULT;
*e = ps->env;
if ((pg=page_lookup(e->env_pgdir, (void *)(USTACKTOP-PGSIZE), NULL))==NULL)
return -E_FAULT;
memmove(page2kva(pg), ps->stack, PGSIZE);
return 0;
}
bool
copy_string(struct mm_struct *mm, char *dst, const char *src, size_t maxn) {
size_t alen, part = ROUNDDOWN((uintptr_t)src + PGSIZE, PGSIZE) - (uintptr_t)src;
while (1) {
if (part > maxn) {
part = maxn;
}
if (!user_mem_check(mm, (uintptr_t)src, part, 0)) {
return 0;
}
if ((alen = strnlen(src, part)) < part) {
memcpy(dst, src, alen + 1);
return 1;
}
if (part == maxn) {
return 0;
}
memcpy(dst, src, part);
dst += part, src += part, maxn -= part;
part = PGSIZE;
}
}
// Send packet
static int
sys_send_packet(void *va, unsigned int size) {
int perm;
int offset;
int r;
struct Page *p;
perm = PTE_U;
if(va + size >= (void *)UTOP) {
cprintf("SYS_send_packet: above UTOP\n");
return -E_INVAL;
}
if((r = user_mem_check(curenv, va, size, perm)) <0) {
cprintf("SYS_send_packet: %08x\n",r);
return r;
}
if(size > MAX_ETH_FRAME_SIZE) {
//should fix the size ...
cprintf("SYS_send_packet: size is too big!");
return -E_INVAL; //better return?
}
//cprintf("Transmitting.......\n\n\n\n");
return e100_send_packet(va, size);
}
// do_wait - wait one OR any children with PROC_ZOMBIE state, and free memory space of kernel stack
// - proc struct of this child.
// NOTE: only after do_wait function, all resources of the child proces are free.
int do_wait(int pid, int *code_store)
{
struct mm_struct *mm = current->mm;
if (code_store != NULL) {
if (!user_mem_check(mm, (uintptr_t) code_store, sizeof(int), 1)) {
return -E_INVAL;
}
}
struct proc_struct *proc, *cproc;
bool intr_flag, haskid;
repeat:
cproc = current;
haskid = 0;
if (pid != 0) {
proc = find_proc(pid);
if (proc != NULL) {
do {
if (proc->parent == cproc) {
haskid = 1;
if (proc->state == PROC_ZOMBIE) {
goto found;
}
break;
}
cproc = next_thread(cproc);
} while (cproc != current);
}
} else {
do {
proc = cproc->cptr;
for (; proc != NULL; proc = proc->optr) {
haskid = 1;
if (proc->state == PROC_ZOMBIE) {
goto found;
}
}
cproc = next_thread(cproc);
} while (cproc != current);
}
if (haskid) {
current->state = PROC_SLEEPING;
current->wait_state = WT_CHILD;
schedule();
may_killed();
goto repeat;
}
return -E_BAD_PROC;
found:
if (proc == idleproc || proc == initproc) {
panic("wait idleproc or initproc.\n");
}
int exit_code = proc->exit_code;
spin_lock_irqsave(&proc_lock, intr_flag);
{
unhash_proc(proc);
remove_links(proc);
}
spin_unlock_irqrestore(&proc_lock, intr_flag);
put_kstack(proc);
kfree(proc);
int ret = 0;
if (code_store != NULL) {
lock_mm(mm);
{
if (!copy_to_user
(mm, code_store, &exit_code, sizeof(int))) {
ret = -E_INVAL;
}
}
unlock_mm(mm);
}
return ret;
}
// debuginfo_eip(addr, info)
//
// Fill in the 'info' structure with information about the specified
// instruction address, 'addr'. Returns 0 if information was found, and
// negative if not. But even if it returns negative it has stored some
// information into '*info'.
//
int
debuginfo_eip(uintptr_t addr, struct Eipdebuginfo *info)
{
const struct Stab *stabs, *stab_end;
const char *stabstr, *stabstr_end;
int lfile, rfile, lfun, rfun, lline, rline;
// Initialize *info
info->eip_file = "<unknown>";
info->eip_line = 0;
info->eip_fn_name = "<unknown>";
info->eip_fn_namelen = 9;
info->eip_fn_addr = addr;
info->eip_fn_narg = 0;
// Find the relevant set of stabs
if (addr >= ULIM) {
stabs = __STAB_BEGIN__;
stab_end = __STAB_END__;
stabstr = __STABSTR_BEGIN__;
stabstr_end = __STABSTR_END__;
} else {
// The user-application linker script, user/user.ld,
// puts information about the application's stabs (equivalent
// to __STAB_BEGIN__, __STAB_END__, __STABSTR_BEGIN__, and
// __STABSTR_END__) in a structure located at virtual address
// USTABDATA.
const struct UserStabData *usd = (const struct UserStabData *) USTABDATA;
// Make sure this memory is valid.
// Return -1 if it is not. Hint: Call user_mem_check.
// LAB 3: Your code here.
if(user_mem_check(curenv, usd, sizeof(struct UserStabData), PTE_U) < 0)
{
return -1;
}
stabs = usd->stabs;
stab_end = usd->stab_end;
stabstr = usd->stabstr;
stabstr_end = usd->stabstr_end;
// Make sure the STABS and string table memory is valid.
// LAB 3: Your code here.
if(user_mem_check(curenv, stabs, stab_end-stabs, PTE_U) < 0)
{
return -1;
}
if(user_mem_check(curenv, stabstr, stabstr_end-stabstr, PTE_U) < 0)
{
return -1;
}
}
// String table validity checks
if (stabstr_end <= stabstr || stabstr_end[-1] != 0)
return -1;
// Now we find the right stabs that define the function containing
// 'eip'. First, we find the basic source file containing 'eip'.
// Then, we look in that source file for the function. Then we look
// for the line number.
// Search the entire set of stabs for the source file (type N_SO).
lfile = 0;
rfile = (stab_end - stabs) - 1;
stab_binsearch(stabs, &lfile, &rfile, N_SO, addr);
if (lfile == 0)
return -1;
// Search within that file's stabs for the function definition
// (N_FUN).
lfun = lfile;
rfun = rfile;
stab_binsearch(stabs, &lfun, &rfun, N_FUN, addr);
if (lfun <= rfun) {
// stabs[lfun] points to the function name
// in the string table, but check bounds just in case.
if (stabs[lfun].n_strx < stabstr_end - stabstr)
info->eip_fn_name = stabstr + stabs[lfun].n_strx;
info->eip_fn_addr = stabs[lfun].n_value;
addr -= info->eip_fn_addr;
// Search within the function definition for the line number.
lline = lfun;
rline = rfun;
} else {
// Couldn't find function stab! Maybe we're in an assembly
// file. Search the whole file for the line number.
info->eip_fn_addr = addr;
lline = lfile;
rline = rfile;
}
// Ignore stuff after the colon.
info->eip_fn_namelen = strfind(info->eip_fn_name, ':') - info->eip_fn_name;
// Search within [lline, rline] for the line number stab.
// If found, set info->eip_line to the right line number.
// If not found, return -1.
//
// Hint:
// There's a particular stabs type used for line numbers.
// Look at the STABS documentation and <inc/stab.h> to find
// which one.
// Your code here.
stab_binsearch(stabs, &lline, &rline, N_SLINE, addr);
if (lline <= rline)
{
info->eip_line = stabs[lline].n_desc;
}
else
{
return -1;
}
// Search backwards from the line number for the relevant filename
// stab.
// We can't just use the "lfile" stab because inlined functions
// can interpolate code from a different file!
// Such included source files use the N_SOL stab type.
while (lline >= lfile
&& stabs[lline].n_type != N_SOL
&& (stabs[lline].n_type != N_SO || !stabs[lline].n_value))
lline--;
if (lline >= lfile && stabs[lline].n_strx < stabstr_end - stabstr)
info->eip_file = stabstr + stabs[lline].n_strx;
// Set eip_fn_narg to the number of arguments taken by the function,
// or 0 if there was no containing function.
if (lfun < rfun)
for (lline = lfun + 1;
lline < rfun && stabs[lline].n_type == N_PSYM;
lline++)
info->eip_fn_narg++;
return 0;
}
int
do_linux_waitpid(int pid, int *code_store) {
struct mm_struct *mm = current->mm;
if (code_store != NULL) {
if (!user_mem_check(mm, (uintptr_t)code_store, sizeof(int), 1)) {
return -E_INVAL;
}
}
struct proc_struct *proc, *cproc;
bool intr_flag, haskid;
repeat:
cproc = current;
haskid = 0;
if (pid > 0) {
proc = find_proc(pid);
if (proc != NULL) {
do {
if (proc->parent == cproc) {
haskid = 1;
if (proc->state == PROC_ZOMBIE) {
goto found;
}
break;
}
cproc = next_thread(cproc);
} while (cproc != current);
}
}
/* we do NOT have group id, so..*/
else if(pid==0 || pid==-1){ /* pid == 0 */
do {
proc = cproc->cptr;
for (; proc != NULL; proc = proc->optr) {
haskid = 1;
if (proc->state == PROC_ZOMBIE) {
goto found;
}
}
cproc = next_thread(cproc);
} while (cproc != current);
}else{ //pid<-1
//TODO
return -E_INVAL;
}
if (haskid) {
current->state = PROC_SLEEPING;
current->wait_state = WT_CHILD;
schedule();
may_killed();
goto repeat;
}
return -E_BAD_PROC;
found:
if (proc == idleproc || proc == initproc) {
panic("wait idleproc or initproc.\n");
}
int exit_code = proc->exit_code;
int return_pid = proc->pid;
local_intr_save(intr_flag);
{
unhash_proc(proc);
remove_links(proc);
}
local_intr_restore(intr_flag);
put_kstack(proc);
kfree(proc);
int ret = 0;
if (code_store != NULL) {
lock_mm(mm);
{
int status = exit_code << 8;
if (!copy_to_user(mm, code_store, &status, sizeof(int))) {
ret = -E_INVAL;
}
}
unlock_mm(mm);
}
return (ret == 0) ? return_pid : ret;
}