From: Lukas Wunner <lukas@wunner.de> Date: Mon, 7 Dec 2020 08:17:06 +0000 (+0100) Subject: spi: rpc-if: Fix use-after-free on unbind X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=393f981ca5f797b58b882d42b7621fb6e43c7f5b;p=linux.git spi: rpc-if: Fix use-after-free on unbind rpcif_spi_remove() accesses the driver's private data after calling spi_unregister_controller() even though that function releases the last reference on the spi_controller and thereby frees the private data. Fix by switching over to the new devm_spi_alloc_master() helper which keeps the private data accessible until the driver has unbound. Fixes: eb8d6d464a27 ("spi: add Renesas RPC-IF driver") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: <stable@vger.kernel.org> # v5.9+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation Cc: <stable@vger.kernel.org> # v5.9+ Cc: Sergei Shtylyov <s.shtylyov@omprussia.ru> Link: https://lore.kernel.org/r/c5da472c28021da2f6517441685cef033d40b140.1607286887.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org> --- diff --git a/drivers/spi/spi-rpc-if.c b/drivers/spi/spi-rpc-if.c index ed3e548227f47..3579675485a5e 100644 --- a/drivers/spi/spi-rpc-if.c +++ b/drivers/spi/spi-rpc-if.c @@ -134,7 +134,7 @@ static int rpcif_spi_probe(struct platform_device *pdev) struct rpcif *rpc; int error; - ctlr = spi_alloc_master(&pdev->dev, sizeof(*rpc)); + ctlr = devm_spi_alloc_master(&pdev->dev, sizeof(*rpc)); if (!ctlr) return -ENOMEM; @@ -159,13 +159,8 @@ static int rpcif_spi_probe(struct platform_device *pdev) error = spi_register_controller(ctlr); if (error) { dev_err(&pdev->dev, "spi_register_controller failed\n"); - goto err_put_ctlr; + rpcif_disable_rpm(rpc); } - return 0; - -err_put_ctlr: - rpcif_disable_rpm(rpc); - spi_controller_put(ctlr); return error; }