ep_create_wakeup_source(): dentry name can change under you...
commit 3701cb59d892b88d569427586f01491552f377b1 upstream.
or get freed, for that matter, if it's a long (separately stored)
name.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 333bb8f..339453a 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1453,7 +1453,7 @@
static int ep_create_wakeup_source(struct epitem *epi)
{
- const char *name;
+ struct name_snapshot n;
struct wakeup_source *ws;
if (!epi->ep->ws) {
@@ -1462,8 +1462,9 @@
return -ENOMEM;
}
- name = epi->ffd.file->f_path.dentry->d_name.name;
- ws = wakeup_source_register(NULL, name);
+ take_dentry_name_snapshot(&n, epi->ffd.file->f_path.dentry);
+ ws = wakeup_source_register(NULL, n.name.name);
+ release_dentry_name_snapshot(&n);
if (!ws)
return -ENOMEM;