From patchwork Thu Feb 1 15:34:47 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13541364 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 2644215D5BA; Thu, 1 Feb 2024 16:16:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706804160; cv=none; b=heVmmP/6C9SBqCb80Pg/Z1w+PiGGEXU1lL4b98+XT17nYK3FsrFAWnfUuz56Wm+A+8qQUpXbWlkGmXzn2ii87MzFjlaQ9+bWqu3U/1qcneBziwSORDpUWJuqUnf7Vjw8q2eHTvdzro8QQobYGeznIA2BHqiBPPS22KlOWG23UOY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706804160; c=relaxed/simple; bh=NPnmMMbyV1baHC4KsmvnpUoEetauizgbbY4RJQJGnHo=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=BQtIFSYrl41JnnQOktQ5i+WhHxsxYXj9f3WNqg0tje7Ki6kBi+KeyS3bsN1inE4W0hBkBU8n2JNkmqQnSZuOu5SU0tBXPGMIdVOxum4v14vEZtMjGoU0nSDMPfnyaJZ44tBaSAxDeNlUn6wgSC6m/0aJkXZUSAOwQPkwm1mVFPE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id F3886C433A6; Thu, 1 Feb 2024 16:15:59 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.97) (envelope-from ) id 1rVZjc-00000005Tik-47ok; Thu, 01 Feb 2024 11:16:16 -0500 Message-ID: <20240201161616.843551963@goodmis.org> User-Agent: quilt/0.67 Date: Thu, 01 Feb 2024 10:34:47 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Christian Brauner , Al Viro , Ajay Kaher Subject: [PATCH 1/6] eventfs: Warn if an eventfs_inode is freed without is_freed being set References: <20240201153446.138990674@goodmis.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: "Steven Rostedt (Google)" There should never be a case where an evenfs_inode is being freed without is_freed being set. Add a WARN_ON_ONCE() if it ever happens. That would mean there was one too many put_ei()s. Signed-off-by: Steven Rostedt (Google) --- fs/tracefs/event_inode.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 515fdace1eea..ca7daee7c811 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -73,6 +73,9 @@ enum { static void release_ei(struct kref *ref) { struct eventfs_inode *ei = container_of(ref, struct eventfs_inode, kref); + + WARN_ON_ONCE(!ei->is_freed); + kfree(ei->entry_attrs); kfree_const(ei->name); kfree_rcu(ei, rcu); @@ -84,6 +87,14 @@ static inline void put_ei(struct eventfs_inode *ei) kref_put(&ei->kref, release_ei); } +static inline void free_ei(struct eventfs_inode *ei) +{ + if (ei) { + ei->is_freed = 1; + put_ei(ei); + } +} + static inline struct eventfs_inode *get_ei(struct eventfs_inode *ei) { if (ei) @@ -679,7 +690,7 @@ struct eventfs_inode *eventfs_create_dir(const char *name, struct eventfs_inode /* Was the parent freed? */ if (list_empty(&ei->list)) { - put_ei(ei); + free_ei(ei); ei = NULL; } return ei; @@ -770,7 +781,7 @@ struct eventfs_inode *eventfs_create_events_dir(const char *name, struct dentry return ei; fail: - put_ei(ei); + free_ei(ei); tracefs_failed_creating(dentry); return ERR_PTR(-ENOMEM); } @@ -801,9 +812,8 @@ static void eventfs_remove_rec(struct eventfs_inode *ei, int level) list_for_each_entry(ei_child, &ei->children, list) eventfs_remove_rec(ei_child, level + 1); - ei->is_freed = 1; list_del(&ei->list); - put_ei(ei); + free_ei(ei); } /**