From nobody Fri Dec 26 13:26:14 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AD68C328D1 for ; Fri, 5 Jan 2024 18:00:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50BA1C433C7; Fri, 5 Jan 2024 18:00:10 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.97) (envelope-from ) id 1rLoVT-000000012Uu-0E2Y; Fri, 05 Jan 2024 13:01:19 -0500 Message-ID: <20240105180118.917102213@goodmis.org> User-Agent: quilt/0.67 Date: Fri, 05 Jan 2024 13:00:52 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Linus Torvalds , Al Viro , Christian Brauner , Greg Kroah-Hartman Subject: [for-next][PATCH 1/4] eventfs: Have eventfs_iterate() stop immediately if ei->is_freed is set References: <20240105180051.741934288@goodmis.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Steven Rostedt (Google)" If ei->is_freed is set in eventfs_iterate(), it means that the directory that is being iterated on is in the process of being freed. Just exit the loop immediately when that is ever detected, and separate out the return of the entry->callback() from ei->is_freed. Link: https://lore.kernel.org/linux-trace-kernel/20240104220048.016261289@g= oodmis.org Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Mathieu Desnoyers Cc: Andrew Morton Cc: Linus Torvalds Cc: Al Viro Cc: Christian Brauner Cc: Greg Kroah-Hartman Signed-off-by: Steven Rostedt (Google) --- fs/tracefs/event_inode.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 72912b5f9a90..0aca6910efb3 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -788,11 +788,12 @@ static int eventfs_iterate(struct file *file, struct = dir_context *ctx) name =3D entry->name; =20 mutex_lock(&eventfs_mutex); - /* If ei->is_freed, then the event itself may be too */ - if (!ei->is_freed) - r =3D entry->callback(name, &mode, &cdata, &fops); - else - r =3D -1; + /* If ei->is_freed then just bail here, nothing more to do */ + if (ei->is_freed) { + mutex_unlock(&eventfs_mutex); + goto out; + } + r =3D entry->callback(name, &mode, &cdata, &fops); mutex_unlock(&eventfs_mutex); if (r <=3D 0) continue; --=20 2.42.0