eventfs: Fix events beyond NAME_MAX blocking tasks

Eventfs uses simple_lookup(), however, it will fail if the name of the
entry is beyond NAME_MAX length. When this error is encountered, eventfs
still tries to create dentries instead of skipping the dentry creation.
When the dentry is attempted to be created in this state d_wait_lookup()
will loop forever, waiting for the lookup to be removed.

Fix eventfs to return the error in simple_lookup() back to the caller
instead of continuing to try to create the dentry.

Link: https://lore.kernel.org/linux-trace-kernel/20231210213534.497-1-beaub@linux.microsoft.com

Fixes: 6394044955 ("eventfs: Implement eventfs lookup, read, open functions")
Link: https://lore.kernel.org/linux-trace-kernel/20231208183601.GA46-beaub@linux.microsoft.com/
Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Beau Belgrave 2023-12-10 21:35:34 +00:00 committed by Steven Rostedt (Google)
parent b55b0a0d7c
commit 5eaf7f0589
1 changed files with 4 additions and 0 deletions

View File

@ -546,6 +546,8 @@ static struct dentry *eventfs_root_lookup(struct inode *dir,
if (strcmp(ei_child->name, name) != 0)
continue;
ret = simple_lookup(dir, dentry, flags);
if (IS_ERR(ret))
goto out;
create_dir_dentry(ei, ei_child, ei_dentry, true);
created = true;
break;
@ -568,6 +570,8 @@ static struct dentry *eventfs_root_lookup(struct inode *dir,
if (r <= 0)
continue;
ret = simple_lookup(dir, dentry, flags);
if (IS_ERR(ret))
goto out;
create_file_dentry(ei, i, ei_dentry, name, mode, cdata,
fops, true);
break;