From nobody Sat Nov 30 10:45:31 2024 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 C98D719ABAB; Tue, 10 Sep 2024 14:43:56 +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=1725979436; cv=none; b=t/qWAgPtahClTxpBPDn70TgtmRgzwNfnrpTnUG3ktInh7W7aeMLT9phzbNpsMT2CSdmbUzLF/K8pVMjj6rzGvRyoKHF+DwJWoTkiezpOwTuJBnm74iUfAclh/aPcX4FOB1jfrzRjbEPf59hbZz1Y8/3wjgir4ypEzNot309nCHk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725979436; c=relaxed/simple; bh=8ktPfzBt6ih236F5v0U2BPIw8M4SjLXm76j3JdVJj8M=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Z15ooOlKrl9j2RtFshu8SgVBvMhEDam7oTtordfsSDyR3tgH2MdETnJZtcHX4smAEGZfmbMDe6kyBOWRLL+2D8RR0anJVCuog4eVgRm4JPHmeIOURUnPOygyCq/v1NxWborsYBbrCKJF/XPSrkElGQwTxqagWFt7h5PkcK+rx88= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ONK6tnE8; 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="ONK6tnE8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EB431C4CED0; Tue, 10 Sep 2024 14:43:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725979436; bh=8ktPfzBt6ih236F5v0U2BPIw8M4SjLXm76j3JdVJj8M=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=ONK6tnE8nqgbJIU2yJ5xJbPAkSq1Wtim7WQn4Eks/QBzEyGuSkXqjrBqxkZH1gNqr 2hfNs0ZABZl9eK4o0Uazikq3iEc7oSZ61z37wEjy+9U5C9Qya9J/CskVVrKN5D9Lct 0yG1j7WsbV7mQbdjPQg4AYK+oNOwAiKzd0YlZwiAfHlqFDQH4TWOY+dhnEOQXID8yr 2Out4bg8r7bCUvw8YA7M32mVOGvruI4Lf2Vd4fhphnfNM3NKETj9MfzfLJ5AVaxuJa Jo3Y50QdHYtWCtG3UTkVZF/8yiRHjC87YG7z0Lg+VnyyImEq9OknySrQkOGfA1ifgq pEYrLLAOtBQCg== From: Benjamin Tissoires Date: Tue, 10 Sep 2024 23:43:39 +0900 Subject: [PATCH HID v2 03/11] HID: core: remove one more kmemdup on .probe() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20240910-hid-bpf-hid-generic-v2-3-083dfc189e97@kernel.org> References: <20240910-hid-bpf-hid-generic-v2-0-083dfc189e97@kernel.org> In-Reply-To: <20240910-hid-bpf-hid-generic-v2-0-083dfc189e97@kernel.org> To: Jiri Kosina , Peter Hutterer , Vicki Pfau , Shuah Khan Cc: linux-input@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, Benjamin Tissoires X-Mailer: b4 0.14.1 X-Developer-Signature: v=1; a=ed25519-sha256; t=1725979428; l=2284; i=bentiss@kernel.org; s=20230215; h=from:subject:message-id; bh=8ktPfzBt6ih236F5v0U2BPIw8M4SjLXm76j3JdVJj8M=; b=zXJ1whlSNOnhHWGHdrRFTCSgVa1H7tFvYXlnGwJ1z+gWdtW5BeQMnAr8dm3L21tdJjrtVMNpQ a1sV3MgyzGICy+rElYyIhvYUjZbBRr2SpdwmSh7Uu+VvuDdrtvC9AVK X-Developer-Key: i=bentiss@kernel.org; a=ed25519; pk=7D1DyAVh6ajCkuUTudt/chMuXWIJHlv2qCsRkIizvFw= That last kmemdup while opening the report descriptor was required to have a common kfree() on it. Move that kmemdup in the only special case it's required (if there is a .report_fixup()), and add a more elaborated check before freeing hdev->rdesc, to avoid a double free. Signed-off-by: Benjamin Tissoires --- new in v2 --- drivers/hid/hid-core.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 172746a082f9..2b70a12a2135 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -685,7 +685,14 @@ static void hid_close_report(struct hid_device *device) INIT_LIST_HEAD(&report_enum->report_list); } =20 - kfree(device->rdesc); + /* + * If the HID driver had a rdesc_fixup() callback, dev->rdesc + * will be allocated by hid-core and needs to be freed. + * Otherwise, it is either equal to dev_rdesc or bpf_rdesc, in + * which cases it'll be freed later on device removal or destroy. + */ + if (device->rdesc !=3D device->dev_rdesc && device->rdesc !=3D device->bp= f_rdesc) + kfree(device->rdesc); device->rdesc =3D NULL; device->rsize =3D 0; =20 @@ -1206,7 +1213,6 @@ int hid_open_report(struct hid_device *device) struct hid_item item; unsigned int size; const __u8 *start; - __u8 *buf =3D NULL; const __u8 *end; const __u8 *next; int ret; @@ -1233,17 +1239,23 @@ int hid_open_report(struct hid_device *device) * on a copy of our report descriptor so it can * change it. */ - buf =3D kmemdup(start, size, GFP_KERNEL); + __u8 *buf =3D kmemdup(start, size, GFP_KERNEL); + if (buf =3D=3D NULL) return -ENOMEM; =20 start =3D device->driver->report_fixup(device, buf, &size); - } =20 - start =3D kmemdup(start, size, GFP_KERNEL); - kfree(buf); - if (start =3D=3D NULL) - return -ENOMEM; + /* + * The second kmemdup is required in case report_fixup() returns + * a static read-only memory, but we have no idea if that memory + * needs to be cleaned up or not at the end. + */ + start =3D kmemdup(start, size, GFP_KERNEL); + kfree(buf); + if (start =3D=3D NULL) + return -ENOMEM; + } =20 device->rdesc =3D start; device->rsize =3D size; --=20 2.46.0