From mboxrd@z Thu Jan 1 00:00:00 1970 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 97AD72690D6; Tue, 8 Apr 2025 12:28:04 +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=1744115284; cv=none; b=ipnWdA+iLMuOgaNeTbXrv06QkpOCh5qLvs60zRehjEZ0ZuevGeZCDbooeMZzs/2WcRU2uqqWd47WQWazrkq8flK7DZgpEIu3MRx/Npd8yLeMiQBS8QEfy5meUjUiQaaol4eJ9fziFNNaZjIw6Gs1CAhQmZpcBrjohY75/jN3l1c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744115284; c=relaxed/simple; bh=6sfaPXRXIQD52Q+egzDDDffwugzEXemG2fQ7QdBVfkc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WbL5ENsXFKWhAUBocet83mp3IjLiztc/nLGdc37NwXYiOlxKbwfGA3pCDrArKV1NNxz+hzktQ2/T9t4OKHH3zFz2knV3QClJuk61ucC29s8uAhX1R098tLo3a7XSE9ZD79L45zuLEm5o4w0jjAzGYQNiPDa1cScD233w+kf2w9o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=n4TXJaK+; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="n4TXJaK+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 297C3C4CEE5; Tue, 8 Apr 2025 12:28:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744115284; bh=6sfaPXRXIQD52Q+egzDDDffwugzEXemG2fQ7QdBVfkc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=n4TXJaK+MMsQvmsIh+V1c1DgqiFfupksm7lyos8V/2NHScywNBrm7PUPLtby8Fzgy zbJtYzSyr19dzKPUlBtp+XYQ/KH+C9FV6vF3155m/KDM8faiMQY0l4bV2FAJ/PrDSG YyDnXmbNl63irVF5b1rlqZ5HGLNmc87y8eDC8bDU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Masami Hiramatsu , Mathieu Desnoyers , Zheng Yejian , Tengda Wu , "Steven Rostedt (Google)" , Sasha Levin Subject: [PATCH 6.13 416/499] tracing: Correct the refcount if the hist/hist_debug file fails to open Date: Tue, 8 Apr 2025 12:50:28 +0200 Message-ID: <20250408104901.600630108@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104851.256868745@linuxfoundation.org> References: <20250408104851.256868745@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tengda Wu [ Upstream commit 0b4ffbe4888a2c71185eaf5c1a02dd3586a9bc04 ] The function event_{hist,hist_debug}_open() maintains the refcount of 'file->tr' and 'file' through tracing_open_file_tr(). However, it does not roll back these counts on subsequent failure paths, resulting in a refcount leak. A very obvious case is that if the hist/hist_debug file belongs to a specific instance, the refcount leak will prevent the deletion of that instance, as it relies on the condition 'tr->ref == 1' within __remove_instance(). Fix this by calling tracing_release_file_tr() on all failure paths in event_{hist,hist_debug}_open() to correct the refcount. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu Cc: Mathieu Desnoyers Cc: Zheng Yejian Link: https://lore.kernel.org/20250314065335.1202817-1-wutengda@huaweicloud.com Fixes: 1cc111b9cddc ("tracing: Fix uaf issue when open the hist or hist_debug file") Signed-off-by: Tengda Wu Signed-off-by: Steven Rostedt (Google) Signed-off-by: Sasha Levin --- kernel/trace/trace_events_hist.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index ad7419e240556..53dc6719181e5 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -5689,12 +5689,16 @@ static int event_hist_open(struct inode *inode, struct file *file) guard(mutex)(&event_mutex); event_file = event_file_data(file); - if (!event_file) - return -ENODEV; + if (!event_file) { + ret = -ENODEV; + goto err; + } hist_file = kzalloc(sizeof(*hist_file), GFP_KERNEL); - if (!hist_file) - return -ENOMEM; + if (!hist_file) { + ret = -ENOMEM; + goto err; + } hist_file->file = file; hist_file->last_act = get_hist_hit_count(event_file); @@ -5702,9 +5706,14 @@ static int event_hist_open(struct inode *inode, struct file *file) /* Clear private_data to avoid warning in single_open() */ file->private_data = NULL; ret = single_open(file, hist_show, hist_file); - if (ret) + if (ret) { kfree(hist_file); + goto err; + } + return 0; +err: + tracing_release_file_tr(inode, file); return ret; } @@ -5979,7 +5988,10 @@ static int event_hist_debug_open(struct inode *inode, struct file *file) /* Clear private_data to avoid warning in single_open() */ file->private_data = NULL; - return single_open(file, hist_debug_show, file); + ret = single_open(file, hist_debug_show, file); + if (ret) + tracing_release_file_tr(inode, file); + return ret; } const struct file_operations event_hist_debug_fops = { -- 2.39.5