[PATCH] spmi: mediatek: Fix UAF on device remove
flat view
STALE1090d
LANDED
From: Yu-Che Cheng <hidden>
Date: 2023-07-17 09:42:27
Also in:
lkml
Subsystem:
spmi subsystem, the rest · Maintainers:
Stephen Boyd, Linus Torvalds
Landed in mainline as e821d50ab5b9 on 2023-12-15.
The pmif driver data that contains the clocks is allocated along with spmi_controller. On device remove, spmi_controller will be freed first, and then devres , including the clocks, will be cleanup. This leads to UAF because putting the clocks will access the clocks in the pmif driver data, which is already freed along with spmi_controller. This can be reproduced by enabling DEBUG_TEST_DRIVER_REMOVE and building the kernel with KASAN. Fix the UAF issue by using unmanaged clk_bulk_get() and putting the clocks before freeing spmi_controller. Reported-by: Fei Shao <redacted> Signed-off-by: Yu-Che Cheng <redacted> --- drivers/spmi/spmi-mtk-pmif.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/spmi/spmi-mtk-pmif.c b/drivers/spmi/spmi-mtk-pmif.c
index b3c991e1ea40..74b73f9bc222 100644
--- a/drivers/spmi/spmi-mtk-pmif.c
+++ b/drivers/spmi/spmi-mtk-pmif.c@@ -465,7 +465,7 @@ static int mtk_spmi_probe(struct platform_device *pdev) for (i = 0; i < arb->nclks; i++) arb->clks[i].id = pmif_clock_names[i]; - err = devm_clk_bulk_get(&pdev->dev, arb->nclks, arb->clks); + err = clk_bulk_get(&pdev->dev, arb->nclks, arb->clks); if (err) { dev_err(&pdev->dev, "Failed to get clocks: %d\n", err); goto err_put_ctrl;
@@ -474,7 +474,7 @@ static int mtk_spmi_probe(struct platform_device *pdev) err = clk_bulk_prepare_enable(arb->nclks, arb->clks); if (err) { dev_err(&pdev->dev, "Failed to enable clocks: %d\n", err); - goto err_put_ctrl; + goto err_put_clks; } ctrl->cmd = pmif_arb_cmd;
@@ -498,6 +498,8 @@ static int mtk_spmi_probe(struct platform_device *pdev) err_domain_remove: clk_bulk_disable_unprepare(arb->nclks, arb->clks); +err_put_clks: + clk_bulk_put(arb->nclks, arb->clks); err_put_ctrl: spmi_controller_put(ctrl); return err;
@@ -509,6 +511,7 @@ static void mtk_spmi_remove(struct platform_device *pdev) struct pmif *arb = spmi_controller_get_drvdata(ctrl); clk_bulk_disable_unprepare(arb->nclks, arb->clks); + clk_bulk_put(arb->nclks, arb->clks); spmi_controller_remove(ctrl); spmi_controller_put(ctrl); }
--
2.41.0.255.g8b1d071c50-goog
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