From nobody Thu Apr 2 23:53:25 2026 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 4CB5E12E1E9; Thu, 26 Mar 2026 06:23:55 +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=1774506235; cv=none; b=hxW7LOUA/ham7UCheFEaq185P4GcAWlzWYoHHFaOuyLXXpqTbH6wJ3X5XRLJgNeSM/5rubl1rxlMEQkhHczS/eVri73gUEIHk48nHQ4ehnslrGLBq2JLbKmDjODZDOHO3QMDhsFUb/lAUeNiwXeFCkqoEl9CfyXT1uGUhUGFVBw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774506235; c=relaxed/simple; bh=RlvImuIw6Gj0I6frcAflxi6JM5UxJrr64Xql9+sFKw8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=R7AN8YGjnQiaKbN416RoKhj3XccnFCNNG+BzamsXN/1W5T19DvZx+tdxR1JQ/pSDOBMkMP5cZxCVEZbLD1S+LvyVleu5lg0NOkLDbfxXQlLJERl+1oFb3uc3hjMqAch4U89BHlGE+hYvtu9+A/vKa1M4v63+fbt2Mqm7r4yJGik= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BdE/wPLf; 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="BdE/wPLf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 063D8C2BCB1; Thu, 26 Mar 2026 06:23:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774506235; bh=RlvImuIw6Gj0I6frcAflxi6JM5UxJrr64Xql9+sFKw8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BdE/wPLfegTP3LfMONDrnSHdGGjqAP02qzisOsg/6SVv0il2Gz6Zo7psUV2GZR0La UYN1pyOIXYh+3pmFwvWs4Hv8fwX2/wUbJbLr0+gSajvOZmZzOEhVRhhCdVj2O4F3xc YiF0Sf5qct5ls494NsQVYa2Qr6i3X3ExK7hn1VTGkK3dNj7XyZ2729pT/1uqpdVpst 5+K8p+ATViUkRPdZX3bqi2gT85e7lPGApnlbLSxZ2snON6BVR+u7hxTwVrT5F/Rq4a ZZ8PgLYH409iRytJezh4+If98jlziGUqidgTXPbf70Kb2jrCvbXOuqYt/qX1wiXury Exr884/Z7/gBA== From: SeongJae Park To: Cc: SeongJae Park , Andrew Morton , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH 1/2] mm/damon/sysfs: dealloc repeat_call_control if damon_call() fails Date: Wed, 25 Mar 2026 23:23:45 -0700 Message-ID: <20260326062347.88569-2-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260326062347.88569-1-sj@kernel.org> References: <20260326062347.88569-1-sj@kernel.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" damon_call() for repeat_call_control of DAMON_SYSFS could fail if somehow the kdamond is stopped before the damon_call(). It could happen, for example, when te damon context was made for monitroing of a virtual address processes, and the process is terminated immediately, before the damon_call() invocation. In the case, the dyanmically allocated repeat_call_control is not deallocated and leaked. Fix the leak by deallocating the repeat_call_control under the damon_call() failure. This issue is discovered by sashiko [1]. [1] https://lore.kernel.org/20260320020630.962-1-sj@kernel.org Signed-off-by: SeongJae Park --- mm/damon/sysfs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 6a44a2f3d8fc9..eefa959aa30ae 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -1670,7 +1670,8 @@ static int damon_sysfs_turn_damon_on(struct damon_sys= fs_kdamond *kdamond) repeat_call_control->data =3D kdamond; repeat_call_control->repeat =3D true; repeat_call_control->dealloc_on_cancel =3D true; - damon_call(ctx, repeat_call_control); + if (damon_call(ctx, repeat_call_control)) + kfree(repeat_call_control); return err; } =20 --=20 2.47.3