eventfs: Fix a possible null pointer dereference in eventfs_find_events()

In function eventfs_find_events,there is a potential null pointer
that may be caused by calling update_events_attr which will perform
some operations on the members of the ei struct when ei is NULL.

Hence,When ei->is_freed is set,return NULL directly.

Link: https://lore.kernel.org/linux-trace-kernel/20240513053338.63017-1-hao.ge@linux.dev

Cc: stable@vger.kernel.org
Fixes: 8186fff7ab ("tracefs/eventfs: Use root and instance inodes as default ownership")
Signed-off-by: Hao Ge <gehao@kylinos.cn>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Hao Ge 2024-05-13 13:33:38 +08:00 committed by Steven Rostedt (Google)
parent e60b613df8
commit d4e9a96873

View File

@ -345,10 +345,9 @@ static struct eventfs_inode *eventfs_find_events(struct dentry *dentry)
* If the ei is being freed, the ownership of the children
* doesn't matter.
*/
if (ei->is_freed) {
ei = NULL;
break;
}
if (ei->is_freed)
return NULL;
// Walk upwards until you find the events inode
} while (!ei->is_events);