From: Johan Hovold Date: Sun, 29 Oct 2017 12:01:33 +0000 (+0100) Subject: staging: greybus: spilib: fix use-after-free after deregistration X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=5abe8d48471c212c45cbb0d522b70d76325ceac0;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git staging: greybus: spilib: fix use-after-free after deregistration commit 770b03c2ca4aa44d226cf248f86aa23e546147d0 upstream. Remove erroneous spi_master_put() after controller deregistration which would access the already freed spi controller. Note that spi_unregister_master() drops our only controller reference. Fixes: ba3e67001b42 ("greybus: SPI: convert to a gpbridge driver") Signed-off-by: Johan Hovold Reviewed-by: Rui Miguel Silva Acked-by: Viresh Kumar Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/greybus/spilib.c b/drivers/staging/greybus/spilib.c index e97b19148497..1e7321a1404c 100644 --- a/drivers/staging/greybus/spilib.c +++ b/drivers/staging/greybus/spilib.c @@ -544,11 +544,14 @@ int gb_spilib_master_init(struct gb_connection *connection, struct device *dev, return 0; -exit_spi_unregister: - spi_unregister_master(master); exit_spi_put: spi_master_put(master); + return ret; + +exit_spi_unregister: + spi_unregister_master(master); + return ret; } EXPORT_SYMBOL_GPL(gb_spilib_master_init); @@ -558,7 +561,6 @@ void gb_spilib_master_exit(struct gb_connection *connection) struct spi_master *master = gb_connection_get_data(connection); spi_unregister_master(master); - spi_master_put(master); } EXPORT_SYMBOL_GPL(gb_spilib_master_exit);