This is a note to let you know that I've just added the patch titled spi: bcm-qspi: return error if neither hif_mspi nor mspi is available to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: spi-bcm-qspi-return-error-if-neither-hif_mspi-nor-ms.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 5eac33d10c2667b17f978abbd37d508c4a697e90 Author: Jonas Gorski <jonas.gorski@xxxxxxxxx> Date: Thu Jun 29 15:43:05 2023 +0200 spi: bcm-qspi: return error if neither hif_mspi nor mspi is available [ Upstream commit 7c1f23ad34fcdace50275a6aa1e1969b41c6233f ] If neither a "hif_mspi" nor "mspi" resource is present, the driver will just early exit in probe but still return success. Apart from not doing anything meaningful, this would then also lead to a null pointer access on removal, as platform_get_drvdata() would return NULL, which it would then try to dereference when trying to unregister the spi master. Fix this by unconditionally calling devm_ioremap_resource(), as it can handle a NULL res and will then return a viable ERR_PTR() if we get one. The "return 0;" was previously a "goto qspi_resource_err;" where then ret was returned, but since ret was still initialized to 0 at this place this was a valid conversion in 63c5395bb7a9 ("spi: bcm-qspi: Fix use-after-free on unbind"). The issue was not introduced by this commit, only made more obvious. Fixes: fa236a7ef240 ("spi: bcm-qspi: Add Broadcom MSPI driver") Signed-off-by: Jonas Gorski <jonas.gorski@xxxxxxxxx> Reviewed-by: Kamal Dasu <kamal.dasu@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230629134306.95823-1-jonas.gorski@xxxxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c index d933a6eda5fdc..118d9161a7886 100644 --- a/drivers/spi/spi-bcm-qspi.c +++ b/drivers/spi/spi-bcm-qspi.c @@ -1250,13 +1250,9 @@ int bcm_qspi_probe(struct platform_device *pdev, res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mspi"); - if (res) { - qspi->base[MSPI] = devm_ioremap_resource(dev, res); - if (IS_ERR(qspi->base[MSPI])) - return PTR_ERR(qspi->base[MSPI]); - } else { - return 0; - } + qspi->base[MSPI] = devm_ioremap_resource(dev, res); + if (IS_ERR(qspi->base[MSPI])) + return PTR_ERR(qspi->base[MSPI]); res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "bspi"); if (res) {