[PATCH AUTOSEL 4.19 37/73] clk: mvebu: Off by one bugs in cp110_of_clk_get()

From: Sasha Levin
Date: Wed Dec 12 2018 - 23:49:37 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit d9f5b7f5dd0fa74a89de5a7ac1e26366f211ccee ]

These > comparisons should be >= to prevent reading beyond the end of
of the clk_data->hws[] buffer.

The clk_data->hws[] array is allocated in cp110_syscon_common_probe()
when we do:
cp110_clk_data = devm_kzalloc(dev, sizeof(*cp110_clk_data) +
sizeof(struct clk_hw *) * CP110_CLK_NUM,
GFP_KERNEL);
As you can see, it has CP110_CLK_NUM elements which is equivalent to
CP110_MAX_CORE_CLOCKS + CP110_MAX_GATABLE_CLOCKS.

Fixes: d3da3eaef7f4 ("clk: mvebu: new driver for Armada CP110 system controller")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/clk/mvebu/cp110-system-controller.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/mvebu/cp110-system-controller.c b/drivers/clk/mvebu/cp110-system-controller.c
index 75bf7b8f282f..0153c76d4a20 100644
--- a/drivers/clk/mvebu/cp110-system-controller.c
+++ b/drivers/clk/mvebu/cp110-system-controller.c
@@ -202,11 +202,11 @@ static struct clk_hw *cp110_of_clk_get(struct of_phandle_args *clkspec,
unsigned int idx = clkspec->args[1];

if (type == CP110_CLK_TYPE_CORE) {
- if (idx > CP110_MAX_CORE_CLOCKS)
+ if (idx >= CP110_MAX_CORE_CLOCKS)
return ERR_PTR(-EINVAL);
return clk_data->hws[idx];
} else if (type == CP110_CLK_TYPE_GATABLE) {
- if (idx > CP110_MAX_GATABLE_CLOCKS)
+ if (idx >= CP110_MAX_GATABLE_CLOCKS)
return ERR_PTR(-EINVAL);
return clk_data->hws[CP110_MAX_CORE_CLOCKS + idx];
}
--
2.19.1