6.6-stable review patch. If anyone has any objections, please let me know.
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From: Yu-Che Cheng giver@chromium.org
[ Upstream commit e821d50ab5b956ed0effa49faaf29912fd4106d9 ]
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 fshao@chromium.org Signed-off-by: Yu-Che Cheng giver@chromium.org Link: https://lore.kernel.org/r/20230717173934.1.If004a6e055a189c7f2d0724fa814422c... Tested-by: Fei Shao fshao@chromium.org Reviewed-by: Fei Shao fshao@chromium.org Reviewed-by: Chen-Yu Tsai wenst@chromium.org Signed-off-by: Stephen Boyd sboyd@kernel.org Link: https://lore.kernel.org/r/20231206231733.4031901-3-sboyd@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 54c35f5535cb..1261f381cae6 100644 --- a/drivers/spmi/spmi-mtk-pmif.c +++ b/drivers/spmi/spmi-mtk-pmif.c @@ -475,7 +475,7 @@ 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; @@ -484,7 +484,7 @@ 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; @@ -510,6 +510,8 @@ 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; @@ -521,6 +523,7 @@ 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); }