Re: [PATCH 4.14 58/62] mtd: rawnand: atmel: fix OF child-node lookup

Naresh Kamboju
2018-11-26T14:16:30Z

Do you see build failure arm x15 beagleboard on 4.14 due to this patch ?

On Mon, 26 Nov 2018 at 16:31, Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> 4.14-stable review patch. If anyone has any objections, please let me know.
>
> ------------------
>
> From: Johan Hovold <johan@kernel.org>
>
> commit 5d1e9c2212ea6b4dd735e4fc3dd6279a365d5d10 upstream.
>
> Use the new of_get_compatible_child() helper to lookup the nfc child
> node instead of using of_find_compatible_node(), which searches the
> entire tree from a given start node and thus can return an unrelated
> (i.e. non-child) node.
>
> This also addresses a potential use-after-free (e.g. after probe
> deferral) as the tree-wide helper drops a reference to its first
> argument (i.e. the node of the device being probed).
>
> While at it, also fix a related nfc-node reference leak.
>
> Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver")
> Cc: stable <stable@vger.kernel.org> # 4.11
> Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
> Cc: Josh Wu <rainyfeeling@outlook.com>
> Cc: Boris Brezillon <boris.brezillon@bootlin.com>
> Signed-off-by: Johan Hovold <johan@kernel.org>
> Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>
> ---
> drivers/mtd/nand/atmel/nand-controller.c | 11 +++++++----
> 1 file changed, 7 insertions(+), 4 deletions(-)
>
> --- a/drivers/mtd/nand/atmel/nand-controller.c
> +++ b/drivers/mtd/nand/atmel/nand-controller.c
> @@ -2077,8 +2077,7 @@ atmel_hsmc_nand_controller_legacy_init(s
> int ret;
>
> nand_np = dev->of_node;
> - nfc_np = of_find_compatible_node(dev->of_node, NULL,
> - "atmel,sama5d3-nfc");
> + nfc_np = of_get_compatible_child(dev->of_node, "atmel,sama5d3-nfc");
> if (!nfc_np) {
> dev_err(dev, "Could not find device node for sama5d3-nfc\n");
> return -ENODEV;
> @@ -2492,15 +2491,19 @@ static int atmel_nand_controller_probe(s
> }
>
> if (caps->legacy_of_bindings) {
> + struct device_node *nfc_node;
> u32 ale_offs = 21;
>
> /*
> * If we are parsing legacy DT props and the DT contains a
> * valid NFC node, forward the request to the sama5 logic.
> */
> - if (of_find_compatible_node(pdev->dev.of_node, NULL,
> - "atmel,sama5d3-nfc"))
> + nfc_node = of_get_compatible_child(pdev->dev.of_node,
> + "atmel,sama5d3-nfc");
> + if (nfc_node) {
> caps = &atmel_sama5_nand_caps;
> + of_node_put(nfc_node);
> + }
>
> /*
> * Even if the compatible says we are dealing with an
>
>

/drivers/mtd/nand/atmel/nand-controller.c: In function
'atmel_hsmc_nand_controller_legacy_init':
/drivers/mtd/nand/atmel/nand-controller.c:2080:11: error: implicit
declaration of function 'of_get_compatible_child'; did you mean
'of_get_next_available_child'? [-Werror=implicit-function-declaration]
nfc_np = of_get_compatible_child(dev->of_node, "atmel,sama5d3-nfc");
^~~~~~~~~~~~~~~~~~~~~~~
of_get_next_available_child
/drivers/mtd/nand/atmel/nand-controller.c:2080:9: warning: assignment
makes pointer from integer without a cast [-Wint-conversion]
nfc_np = of_get_compatible_child(dev->of_node, "atmel,sama5d3-nfc");
^
/drivers/mtd/nand/atmel/nand-controller.c: In function
'atmel_nand_controller_probe':
/drivers/mtd/nand/atmel/nand-controller.c:2501:12: warning:
assignment makes pointer from integer without a cast
[-Wint-conversion]
nfc_node = of_get_compatible_child(pdev->dev.of_node,
^

Full build log link,
https://ci.linaro.org/job/openembedded-lkft-linux-stable-rc-4.14/DISTRO=rpb,MACHINE=am57xx-evm,label=docker-lkft/336/consoleFull

Best regards
Naresh Kamboju