Lukas Wunner 3e538c536f spi: Prevent adding devices below an unregistering controller ... commit ddf75be47c upstream. CONFIG_OF_DYNAMIC and CONFIG_ACPI allow adding SPI devices at runtime using a DeviceTree overlay or DSDT patch. CONFIG_SPI_SLAVE allows the same via sysfs. But there are no precautions to prevent adding a device below a controller that's being removed. Such a device is unusable and may not even be able to unbind cleanly as it becomes inaccessible once the controller has been torn down. E.g. it is then impossible to quiesce the device's interrupt. of_spi_notify() and acpi_spi_notify() do hold a ref on the controller, but otherwise run lockless against spi_unregister_controller(). Fix by holding the spi_add_lock in spi_unregister_controller() and bailing out of spi_add_device() if the controller has been unregistered concurrently. Fixes: ce79d54ae4 ("spi/of: Add OF notifier handler") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: stable@vger.kernel.org # v3.19+ Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Octavian Purdila <octavian.purdila@intel.com> Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Link: https://lore.kernel.org/r/a8c3205088a969dc8410eec1eba9aface60f36af.1596451035.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-08-26 10:40:50 +02:00
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atmel-quadspi.c
internals.h
Kconfig	spi: Prevent adding devices below an unregistering controller	2020-08-26 10:40:50 +02:00
Makefile
spi-altera.c
spi-armada-3700.c
spi-at91-usart.c
spi-ath79.c
spi-atmel.c
spi-au1550.c
spi-axi-spi-engine.c
spi-bcm63xx-hsspi.c
spi-bcm63xx.c
spi-bcm2835.c
spi-bcm2835aux.c
spi-bcm-qspi.c
spi-bcm-qspi.h
spi-bitbang-txrx.h
spi-bitbang.c
spi-brcmstb-qspi.c
spi-butterfly.c
spi-cadence.c
spi-cavium-octeon.c
spi-cavium-thunderx.c
spi-cavium.c
spi-cavium.h
spi-clps711x.c
spi-coldfire-qspi.c
spi-davinci.c
spi-dln2.c
spi-dw-mid.c
spi-dw-mmio.c
spi-dw-pci.c
spi-dw.c
spi-dw.h
spi-efm32.c
spi-ep93xx.c
spi-falcon.c
spi-fsl-cpm.c
spi-fsl-cpm.h
spi-fsl-dspi.c	spi: spi-fsl-dspi: Fix lockup if device is shutdown during SPI transfer	2020-07-22 09:32:55 +02:00
spi-fsl-espi.c
spi-fsl-lib.c
spi-fsl-lib.h
spi-fsl-lpspi.c
spi-fsl-qspi.c
spi-fsl-spi.c
spi-fsl-spi.h
spi-geni-qcom.c
spi-gpio.c
spi-img-spfi.c
spi-imx.c
spi-iproc-qspi.c
spi-jcore.c
spi-lantiq-ssc.c	spi: lantiq-ssc: Fix warning by using WQ_MEM_RECLAIM	2020-08-19 08:16:14 +02:00
spi-lm70llp.c
spi-loopback-test.c
spi-lp8841-rtc.c
spi-mem.c
spi-meson-spicc.c
spi-meson-spifc.c
spi-mpc52xx-psc.c
spi-mpc52xx.c
spi-mpc512x-psc.c
spi-mt65xx.c	spi: mediatek: use correct SPI_CFG2_REG MACRO	2020-07-29 10:18:37 +02:00
spi-mt7621.c
spi-mxic.c
spi-mxs.c
spi-npcm-fiu.c
spi-npcm-pspi.c
spi-nxp-fspi.c
spi-oc-tiny.c
spi-omap2-mcspi.c
spi-omap-100k.c
spi-omap-uwire.c
spi-orion.c
spi-pic32-sqi.c
spi-pic32.c
spi-pl022.c
spi-ppc4xx.c
spi-pxa2xx-dma.c
spi-pxa2xx-pci.c
spi-pxa2xx.c
spi-pxa2xx.h
spi-qcom-qspi.c
spi-qup.c
spi-rb4xx.c
spi-rockchip.c	spi: rockchip: Fix error in SPI slave pio read	2020-08-19 08:15:58 +02:00
spi-rspi.c
spi-s3c24xx-fiq.h
spi-s3c24xx-fiq.S
spi-s3c24xx.c
spi-s3c64xx.c
spi-sc18is602.c
spi-sh-hspi.c
spi-sh-msiof.c
spi-sh-sci.c
spi-sh.c
spi-sifive.c
spi-sirf.c
spi-slave-mt27xx.c
spi-slave-system-control.c
spi-slave-time.c
spi-sprd-adi.c	spi: sprd: switch the sequence of setting WDG_LOAD_LOW and _HIGH	2020-07-22 09:33:18 +02:00
spi-sprd.c
spi-st-ssc4.c
spi-stm32-qspi.c
spi-stm32.c
spi-sun4i.c
spi-sun6i.c	spi: spi-sun6i: sun6i_spi_transfer_one(): fix setting of clock rate	2020-07-22 09:33:02 +02:00
spi-synquacer.c
spi-tegra20-sflash.c
spi-tegra20-slink.c
spi-tegra114.c
spi-test.h
spi-ti-qspi.c
spi-tle62x0.c
spi-topcliff-pch.c
spi-txx9.c
spi-uniphier.c
spi-xcomm.c
spi-xilinx.c
spi-xlp.c
spi-xtensa-xtfpga.c
spi-zynq-qspi.c
spi-zynqmp-gqspi.c
spi.c	spi: Prevent adding devices below an unregistering controller	2020-08-26 10:40:50 +02:00
spidev.c	spi: spidev: Align buffers for DMA	2020-08-19 08:16:25 +02:00