From patchwork Thu Apr 17 15:09:33 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 14055772 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 D8E52252905; Thu, 17 Apr 2025 15:07:55 +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=1744902475; cv=none; b=A6N4lCQpB1h+qrhzmuHU/1Sh3h4RtnAEgSujvpKu1LE7rQ2Qx0qoajt3UVdlkcw2Y6XjKq2P36aPaVQte/DZ8QJqqnk/QSCYH10vFCxXoonrHk826GJbzVSb8FHF7eJl6+S6rfE2HzFIdNa/w8wSDfdq+UqGt8ULmlkZ6c4BHlo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744902475; c=relaxed/simple; bh=l2G9SIlOjiYGdNKHPZBjPNDB9Y6expiTEh9Ez2pi1XU=; h=Date:From:To:Subject:Message-ID:MIME-Version:Content-Type; b=tJWqLvxBrZ9NXyDoo4zyBqCiMW5nmR5BD4WldKs0rfKdH0sH4A+fN47FmkQmATCJFiwySAxFFfh7GTUEytPLWnS26zz577JMCPPl3+WzkwJZXLUi+fWPJUp0aHd6nl4t9uiAI87UUmRgidCGNIsxslWStP6GOfklsSxdb3Z/h9Q= 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 B8198C4CEE4; Thu, 17 Apr 2025 15:07:54 +0000 (UTC) Date: Thu, 17 Apr 2025 11:09:33 -0400 From: Steven Rostedt To: LKML , Linux Trace Kernel , Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers Subject: [PATCH] ftrace: Reinitialize hash to EMPTY_HASH after freeing Message-ID: <20250417110933.20ab718b@gandalf.local.home> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Steven Rostedt There's several locations that free a ftrace hash pointer but may be referenced again. Reset them to EMPTY_HASH so that a u-a-f bug doesn't happen. Fixes: 0ae6b8ce200d ("ftrace: Fix accounting of subop hashes") Signed-off-by: Steven Rostedt (Google) --- kernel/trace/ftrace.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 66bf4512ec04..39ccbb3b9693 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1297,6 +1297,8 @@ void ftrace_free_filter(struct ftrace_ops *ops) return; free_ftrace_hash(ops->func_hash->filter_hash); free_ftrace_hash(ops->func_hash->notrace_hash); + ops->func_hash->filter_hash = EMPTY_HASH; + ops->func_hash->notrace_hash = EMPTY_HASH; } EXPORT_SYMBOL_GPL(ftrace_free_filter); @@ -3443,6 +3445,7 @@ static int add_next_hash(struct ftrace_hash **filter_hash, struct ftrace_hash ** size_bits); if (ret < 0) { free_ftrace_hash(*filter_hash); + *filter_hash = EMPTY_HASH; return ret; } } @@ -3472,6 +3475,7 @@ static int add_next_hash(struct ftrace_hash **filter_hash, struct ftrace_hash ** subops_hash->notrace_hash); if (ret < 0) { free_ftrace_hash(*notrace_hash); + *notrace_hash = EMPTY_HASH; return ret; } }