From: Jonas Gorski jonas.gorski@gmail.com
[ 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@gmail.com Reviewed-by: Kamal Dasu kamal.dasu@broadcom.com Link: https://lore.kernel.org/r/20230629134306.95823-1-jonas.gorski@gmail.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-bcm-qspi.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c index 0321ac531df7f..cebc06759eeea 100644 --- a/drivers/spi/spi-bcm-qspi.c +++ b/drivers/spi/spi-bcm-qspi.c @@ -1251,13 +1251,9 @@ 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) {