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 005E642CCF3; Sat, 28 Feb 2026 17:46:46 +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=1772300806; cv=none; b=DRhf3mf95nk8N695Qk0HQ2BbKGp3CsU8PjuvbFXA7CwNrrTDhB66m8rHdCgS8zFD+KiuMaCDkgNghuK5juONGqWA7QhTPzUo6F/4brqM2JTO+WLa1/uphzt9BehewJgVw15F4EUkePLh5Sc8LaFUhEaunVFaT2L3eASVj3pwLks= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772300806; c=relaxed/simple; bh=vUinIj0FNWMSLtEF/cm2Xly3yd7xmnPuhsRTpxkw2HI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BPoZadXoLz3j88sjj8OWX9cBLoRfim5ZWcBRupCwNBh2zQknqSX0bthaQEbzUvku60YYtB4XkFV1O+EVi2n8Dask9OJnPYWdEkQgKtJtzvnkwRYPleb9AJALx92UNF3MChTrwA3m+W3F4i3XAWAZ/lAa+KUkHOweb5urZxGfAQo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WXRHBS+s; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WXRHBS+s" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B2EDC19424; Sat, 28 Feb 2026 17:46:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772300805; bh=vUinIj0FNWMSLtEF/cm2Xly3yd7xmnPuhsRTpxkw2HI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WXRHBS+s1qKokdCg8lT/QiqMTnzcvbwvMeaQe21fHnaoItk1kqJ2oAF4blQ8Sj7FX t9bE3gNc6n3rMYP4nI/n3c0QuxRpdiAqV0De8KNQtKa2DYQjEB8AihDe6tbaM3Jhpm TiN7VnU2YCjWhYYMF0SINk/qx1ABmygn9St2Hw42teV3oFE59eY13P0frG8N2jLuAH 9jpUg+fCOdR7s9G59BOuQESVWTVpZwmLJIwL1xO2NQ7pepphX3VhQVyRdIQdCL7m97 u7RxDZu7GbcM9X2npbINFOOyBTapymz1vHPUgvYiqlmJjfk51A7xteNPmIi5CjQb8Z DelpD03Cc8Eig== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Petr Pavlu , Mathieu Desnoyers , Tom Zanussi , "Masami Hiramatsu (Google)" , "Steven Rostedt (Google)" , Sasha Levin Subject: [PATCH 6.19 838/844] tracing: Fix checking of freed trace_event_file for hist files Date: Sat, 28 Feb 2026 12:32:31 -0500 Message-ID: <20260228173244.1509663-839-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228173244.1509663-1-sashal@kernel.org> References: <20260228173244.1509663-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Petr Pavlu [ Upstream commit f0a0da1f907e8488826d91c465f7967a56a95aca ] The event_hist_open() and event_hist_poll() functions currently retrieve a trace_event_file pointer from a file struct by invoking event_file_data(), which simply returns file->f_inode->i_private. The functions then check if the pointer is NULL to determine whether the event is still valid. This approach is flawed because i_private is assigned when an eventfs inode is allocated and remains set throughout its lifetime. Instead, the code should call event_file_file(), which checks for EVENT_FILE_FL_FREED. Using the incorrect access function may result in the code potentially opening a hist file for an event that is being removed or becoming stuck while polling on this file. Correct the access method to event_file_file() in both functions. Cc: stable@vger.kernel.org Cc: Mathieu Desnoyers Cc: Tom Zanussi Link: https://patch.msgid.link/20260219162737.314231-2-petr.pavlu@suse.com Fixes: 1bd13edbbed6 ("tracing/hist: Add poll(POLLIN) support on hist file") Signed-off-by: Petr Pavlu Acked-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) Signed-off-by: Sasha Levin --- kernel/trace/trace_events_hist.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 7e50df8b800b1..864aa33712ce4 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -5778,7 +5778,7 @@ static __poll_t event_hist_poll(struct file *file, struct poll_table_struct *wai guard(mutex)(&event_mutex); - event_file = event_file_data(file); + event_file = event_file_file(file); if (!event_file) return EPOLLERR; @@ -5816,7 +5816,7 @@ static int event_hist_open(struct inode *inode, struct file *file) guard(mutex)(&event_mutex); - event_file = event_file_data(file); + event_file = event_file_file(file); if (!event_file) { ret = -ENODEV; goto err; -- 2.51.0