Re: [PATCH v4] proc: Allow pid_revalidate() during LOOKUP_RCU
flat view
From: Al Viro <viro@zeniv.linux.org.uk>
Date: 2021-01-05 17:46:44
Also in:
linux-fsdevel, lkml, selinux
On Tue, Jan 05, 2021 at 04:50:05PM +0000, Al Viro wrote:
struct dentry *d_find_alias_rcu(struct inode *inode)
{
struct hlist_head *l = &inode->i_dentry;
struct dentry *de = NULL;
spin_lock(&inode->i_lock);
// ->i_dentry and ->i_rcu are colocated, but the latter won't be
// used without having I_FREEING set, which means no aliases left
if (inode->i_state & I_FREEING) {
spin_unlock(&inode->i_lock);
return NULL;
}
// we can safely access inode->i_dentry
if (hlist_empty(p)) {
if (hlist_empty(l)) {
obviously...