proc: Better ownership of files for non-dumpable tasks in user namespaces

Instead of making the files owned by the GLOBAL_ROOT_USER.  Make
non-dumpable files whose mm has always lived in a user namespace owned
by the user namespace root.  This allows the container root to have
things work as expected in a container.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman
2017-01-03 10:23:11 +13:00
parent 9227dd2a84
commit 68eb94f162
3 changed files with 61 additions and 69 deletions

View File

@@ -84,7 +84,6 @@ static int tid_fd_revalidate(struct dentry *dentry, unsigned int flags)
{
struct files_struct *files;
struct task_struct *task;
const struct cred *cred;
struct inode *inode;
unsigned int fd;
@@ -108,16 +107,7 @@ static int tid_fd_revalidate(struct dentry *dentry, unsigned int flags)
rcu_read_unlock();
put_files_struct(files);
if (task_dumpable(task)) {
rcu_read_lock();
cred = __task_cred(task);
inode->i_uid = cred->euid;
inode->i_gid = cred->egid;
rcu_read_unlock();
} else {
inode->i_uid = GLOBAL_ROOT_UID;
inode->i_gid = GLOBAL_ROOT_GID;
}
task_dump_owner(task, 0, &inode->i_uid, &inode->i_gid);
if (S_ISLNK(inode->i_mode)) {
unsigned i_mode = S_IFLNK;