X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Fproc%2Fbase.c;h=51be1ce34a0592cf4cd6d4853acfc0ec6e9a843c;hb=94b798ff0d7d4c30e38f9b61fc29fd17472221f9;hp=851ba3dcdc290ab6b750793c2840bdffac755de7;hpb=c292fe4aae5aa5c089633bc40342d27c8275306a;p=pandora-kernel.git

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 851ba3dcdc29..51be1ce34a05 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -194,65 +194,7 @@ static int proc_root_link(struct inode *inode, struct path *path)
 	return result;
 }
 
-static struct mm_struct *__check_mem_permission(struct task_struct *task)
-{
-	struct mm_struct *mm;
-
-	mm = get_task_mm(task);
-	if (!mm)
-		return ERR_PTR(-EINVAL);
-
-	/*
-	 * A task can always look at itself, in case it chooses
-	 * to use system calls instead of load instructions.
-	 */
-	if (task == current)
-		return mm;
-
-	/*
-	 * If current is actively ptrace'ing, and would also be
-	 * permitted to freshly attach with ptrace now, permit it.
-	 */
-	if (task_is_stopped_or_traced(task)) {
-		int match;
-		rcu_read_lock();
-		match = (ptrace_parent(task) == current);
-		rcu_read_unlock();
-		if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH))
-			return mm;
-	}
-
-	/*
-	 * No one else is allowed.
-	 */
-	mmput(mm);
-	return ERR_PTR(-EPERM);
-}
-
-/*
- * If current may access user memory in @task return a reference to the
- * corresponding mm, otherwise ERR_PTR.
- */
-static struct mm_struct *check_mem_permission(struct task_struct *task)
-{
-	struct mm_struct *mm;
-	int err;
-
-	/*
-	 * Avoid racing if task exec's as we might get a new mm but validate
-	 * against old credentials.
-	 */
-	err = mutex_lock_killable(&task->signal->cred_guard_mutex);
-	if (err)
-		return ERR_PTR(err);
-
-	mm = __check_mem_permission(task);
-	mutex_unlock(&task->signal->cred_guard_mutex);
-
-	return mm;
-}
-
-struct mm_struct *mm_for_maps(struct task_struct *task)
+static struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
 {
 	struct mm_struct *mm;
 	int err;
@@ -263,7 +205,7 @@ struct mm_struct *mm_for_maps(struct task_struct *task)
 
 	mm = get_task_mm(task);
 	if (mm && mm != current->mm &&
-			!ptrace_may_access(task, PTRACE_MODE_READ)) {
+			!ptrace_may_access(task, mode)) {
 		mmput(mm);
 		mm = ERR_PTR(-EACCES);
 	}
@@ -272,6 +214,11 @@ struct mm_struct *mm_for_maps(struct task_struct *task)
 	return mm;
 }
 
+struct mm_struct *mm_for_maps(struct task_struct *task)
+{
+	return mm_access(task, PTRACE_MODE_READ_FSCREDS);
+}
+
 static int proc_pid_cmdline(struct task_struct *task, char * buffer)
 {
 	int res = 0;
@@ -341,7 +288,7 @@ static int proc_pid_wchan(struct task_struct *task, char *buffer)
 	wchan = get_wchan(task);
 
 	if (lookup_symbol_name(wchan, symname) < 0)
-		if (!ptrace_may_access(task, PTRACE_MODE_READ))
+		if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
 			return 0;
 		else
 			return sprintf(buffer, "%lu", wchan);
@@ -355,7 +302,7 @@ static int lock_trace(struct task_struct *task)
 	int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
 	if (err)
 		return err;
-	if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
+	if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {
 		mutex_unlock(&task->signal->cred_guard_mutex);
 		return -EPERM;
 	}
@@ -597,7 +544,7 @@ static int proc_fd_access_allowed(struct inode *inode)
 	 */
 	task = get_proc_task(inode);
 	if (task) {
-		allowed = ptrace_may_access(task, PTRACE_MODE_READ);
+		allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
 		put_task_struct(task);
 	}
 	return allowed;
@@ -611,7 +558,7 @@ int proc_setattr(struct dentry *dentry, struct iattr *attr)
 	if (attr->ia_valid & ATTR_MODE)
 		return -EPERM;
 
-	error = inode_change_ok(inode, attr);
+	error = setattr_prepare(dentry, attr);
 	if (error)
 		return error;
 
@@ -815,134 +762,97 @@ static const struct file_operations proc_single_file_operations = {
 };
 
 static int mem_open(struct inode* inode, struct file* file)
-{
-	file->private_data = (void*)((long)current->self_exec_id);
-	/* OK to pass negative loff_t, we can catch out-of-range */
-	file->f_mode |= FMODE_UNSIGNED_OFFSET;
-	return 0;
-}
-
-static ssize_t mem_read(struct file * file, char __user * buf,
-			size_t count, loff_t *ppos)
 {
 	struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
-	char *page;
-	unsigned long src = *ppos;
-	int ret = -ESRCH;
 	struct mm_struct *mm;
 
 	if (!task)
-		goto out_no_task;
+		return -ESRCH;
 
-	ret = -ENOMEM;
-	page = (char *)__get_free_page(GFP_TEMPORARY);
-	if (!page)
-		goto out;
+	mm = mm_access(task, PTRACE_MODE_ATTACH | PTRACE_MODE_FSCREDS);
+	put_task_struct(task);
 
-	mm = check_mem_permission(task);
-	ret = PTR_ERR(mm);
 	if (IS_ERR(mm))
-		goto out_free;
-
-	ret = -EIO;
- 
-	if (file->private_data != (void*)((long)current->self_exec_id))
-		goto out_put;
+		return PTR_ERR(mm);
 
-	ret = 0;
- 
-	while (count > 0) {
-		int this_len, retval;
-
-		this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
-		retval = access_remote_vm(mm, src, page, this_len, 0);
-		if (!retval) {
-			if (!ret)
-				ret = -EIO;
-			break;
-		}
-
-		if (copy_to_user(buf, page, retval)) {
-			ret = -EFAULT;
-			break;
-		}
- 
-		ret += retval;
-		src += retval;
-		buf += retval;
-		count -= retval;
+	if (mm) {
+		/* ensure this mm_struct can't be freed */
+		atomic_inc(&mm->mm_count);
+		/* but do not pin its memory */
+		mmput(mm);
 	}
-	*ppos = src;
 
-out_put:
-	mmput(mm);
-out_free:
-	free_page((unsigned long) page);
-out:
-	put_task_struct(task);
-out_no_task:
-	return ret;
+	/* OK to pass negative loff_t, we can catch out-of-range */
+	file->f_mode |= FMODE_UNSIGNED_OFFSET;
+	file->private_data = mm;
+
+	return 0;
 }
 
-static ssize_t mem_write(struct file * file, const char __user *buf,
-			 size_t count, loff_t *ppos)
+static ssize_t mem_rw(struct file *file, char __user *buf,
+			size_t count, loff_t *ppos, int write)
 {
-	int copied;
+	struct mm_struct *mm = file->private_data;
+	unsigned long addr = *ppos;
+	ssize_t copied;
 	char *page;
-	struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
-	unsigned long dst = *ppos;
-	struct mm_struct *mm;
 
-	copied = -ESRCH;
-	if (!task)
-		goto out_no_task;
+	if (!mm)
+		return 0;
 
-	copied = -ENOMEM;
 	page = (char *)__get_free_page(GFP_TEMPORARY);
 	if (!page)
-		goto out_task;
-
-	mm = check_mem_permission(task);
-	copied = PTR_ERR(mm);
-	if (IS_ERR(mm))
-		goto out_free;
-
-	copied = -EIO;
-	if (file->private_data != (void *)((long)current->self_exec_id))
-		goto out_mm;
+		return -ENOMEM;
 
 	copied = 0;
+	if (!atomic_inc_not_zero(&mm->mm_users))
+		goto free;
+
 	while (count > 0) {
-		int this_len, retval;
+		int this_len = min_t(int, count, PAGE_SIZE);
 
-		this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
-		if (copy_from_user(page, buf, this_len)) {
+		if (write && copy_from_user(page, buf, this_len)) {
 			copied = -EFAULT;
 			break;
 		}
-		retval = access_remote_vm(mm, dst, page, this_len, 1);
-		if (!retval) {
+
+		this_len = access_remote_vm(mm, addr, page, this_len, write);
+		if (!this_len) {
 			if (!copied)
 				copied = -EIO;
 			break;
 		}
-		copied += retval;
-		buf += retval;
-		dst += retval;
-		count -= retval;			
+
+		if (!write && copy_to_user(buf, page, this_len)) {
+			copied = -EFAULT;
+			break;
+		}
+
+		buf += this_len;
+		addr += this_len;
+		copied += this_len;
+		count -= this_len;
 	}
-	*ppos = dst;
+	*ppos = addr;
 
-out_mm:
 	mmput(mm);
-out_free:
+free:
 	free_page((unsigned long) page);
-out_task:
-	put_task_struct(task);
-out_no_task:
 	return copied;
 }
 
+static ssize_t mem_read(struct file *file, char __user *buf,
+			size_t count, loff_t *ppos)
+{
+	return mem_rw(file, buf, count, ppos, 0);
+}
+
+static ssize_t mem_write(struct file *file, const char __user *buf,
+			 size_t count, loff_t *ppos)
+{
+	return mem_rw(file, (char __user*)buf, count, ppos, 1);
+}
+
 loff_t mem_lseek(struct file *file, loff_t offset, int orig)
 {
 	switch (orig) {
@@ -959,11 +869,20 @@ loff_t mem_lseek(struct file *file, loff_t offset, int orig)
 	return file->f_pos;
 }
 
+static int mem_release(struct inode *inode, struct file *file)
+{
+	struct mm_struct *mm = file->private_data;
+	if (mm)
+		mmdrop(mm);
+	return 0;
+}
+
 static const struct file_operations proc_mem_operations = {
 	.llseek		= mem_lseek,
 	.read		= mem_read,
 	.write		= mem_write,
 	.open		= mem_open,
+	.release	= mem_release,
 };
 
 static ssize_t environ_read(struct file *file, char __user *buf,
@@ -986,7 +905,8 @@ static ssize_t environ_read(struct file *file, char __user *buf,
 
 	mm = mm_for_maps(task);
 	ret = PTR_ERR(mm);
-	if (!mm || IS_ERR(mm))
+	/* Ensure the process spawned far enough to have an environment. */
+	if (!mm || IS_ERR(mm) || !mm->env_end)
 		goto out_free;
 
 	ret = 0;
@@ -1911,7 +1831,7 @@ static int proc_fd_info(struct inode *inode, struct path *path, char *info)
 
 			fdt = files_fdtable(files);
 			f_flags = file->f_flags & ~O_CLOEXEC;
-			if (FD_ISSET(fd, fdt->close_on_exec))
+			if (close_on_exec(fd, fdt))
 				f_flags |= O_CLOEXEC;
 
 			if (path) {
@@ -2707,7 +2627,7 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
 	if (result)
 		return result;
 
-	if (!ptrace_may_access(task, PTRACE_MODE_READ)) {
+	if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
 		result = -EACCES;
 		goto out_unlock;
 	}
@@ -2796,6 +2716,7 @@ static const struct pid_entry tgid_base_stuff[] = {
 	ONE("stat",       S_IRUGO, proc_tgid_stat),
 	ONE("statm",      S_IRUGO, proc_pid_statm),
 	REG("maps",       S_IRUGO, proc_maps_operations),
+	REG("arm_maps",   S_IRUGO, proc_armv7_maps_operations),
 #ifdef CONFIG_NUMA
 	REG("numa_maps",  S_IRUGO, proc_numa_maps_operations),
 #endif
@@ -3142,6 +3063,7 @@ static const struct pid_entry tid_base_stuff[] = {
 	ONE("stat",      S_IRUGO, proc_tid_stat),
 	ONE("statm",     S_IRUGO, proc_pid_statm),
 	REG("maps",      S_IRUGO, proc_maps_operations),
+	REG("arm_maps",  S_IRUGO, proc_armv7_maps_operations),
 #ifdef CONFIG_NUMA
 	REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
 #endif