4.15-stable review patch. If anyone has any objections, please let me know.
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From: Jerome Brunet jbrunet@baylibre.com
[ Upstream commit 29fd2a34ef8d863e48183bd473ba57c8d7839e25 ]
Nothing really prevents a provider from (trying to) register a clock without providing the clock ops structure.
We do check the individual fields before using them, but not the structure pointer itself. This may have the usual nasty consequences when the pointer is dereferenced, most likely when checking one the field during the initialization.
This is fixed by returning an error on clock register if the ops pointer is NULL.
Signed-off-by: Jerome Brunet jbrunet@baylibre.com Signed-off-by: Michael Turquette mturquette@baylibre.com Link: lkml.kernel.org/r/20171219083329.24746-1-jbrunet@baylibre.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/clk/clk.c | 7 +++++++ 1 file changed, 7 insertions(+)
--- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -2684,7 +2684,13 @@ struct clk *clk_register(struct device * ret = -ENOMEM; goto fail_name; } + + if (WARN_ON(!hw->init->ops)) { + ret = -EINVAL; + goto fail_ops; + } core->ops = hw->init->ops; + if (dev && pm_runtime_enabled(dev)) core->dev = dev; if (dev && dev->driver) @@ -2746,6 +2752,7 @@ fail_parent_names_copy: kfree_const(core->parent_names[i]); kfree(core->parent_names); fail_parent_names: +fail_ops: kfree_const(core->name); fail_name: kfree(core);