`struct clk_hw_onecell_data` is a flexible structure, which means that
it contains flexible-array member at the bottom, in this case array
`hws`:
include/linux/clk-provider.h:
1380 struct clk_hw_onecell_data {
1381 unsigned int num;
1382 struct clk_hw *hws[] __counted_by(num);
1383 };
This could potentially lead to an overwrite of the objects following
`clk_data` in `struct stratix10_clock_data`, in this case
`void __iomem *base;` at run-time:
drivers/clk/socfpga/stratix10-clk.h:
9 struct stratix10_clock_data {
10 struct clk_hw_onecell_data clk_data;
11 void __iomem *base;
12 };
There are currently three different places where memory is allocated for
`struct stratix10_clock_data`, including the flex-array `hws` in
`struct clk_hw_onecell_data`:
drivers/clk/socfpga/clk-agilex.c:
469 clk_data = devm_kzalloc(dev, struct_size(clk_data, clk_data.hws,
470 num_clks), GFP_KERNEL);
drivers/clk/socfpga/clk-agilex.c:
509 clk_data = devm_kzalloc(dev, struct_size(clk_data, clk_data.hws,
510 num_clks), GFP_KERNEL);
drivers/clk/socfpga/clk-s10.c:
400 clk_data = devm_kzalloc(dev, struct_size(clk_data, clk_data.hws,
401 num_clks), GFP_KERNEL);
I'll use just one of them to describe the issue. See below.
Notice that a total of 440 bytes are allocated for flexible-array member
`hws` at line 469:
include/dt-bindings/clock/agilex-clock.h:
70 #define AGILEX_NUM_CLKS 55
drivers/clk/socfpga/clk-agilex.c:
459 struct stratix10_clock_data *clk_data;
460 void __iomem *base;
...
466
467 num_clks = AGILEX_NUM_CLKS;
468
469 clk_data = devm_kzalloc(dev, struct_size(clk_data, clk_data.hws,
470 num_clks), GFP_KERNEL);
`struct_size(clk_data, clk_data.hws, num_clks)` above translates to
sizeof(struct stratix10_clock_data) + sizeof(struct clk_hw *) * 55 ==
16 + 8 * 55 == 16 + 440
^^^
|
allocated bytes for flex-array `hws`
474 for (i = 0; i < num_clks; i++)
475 clk_data->clk_data.hws[i] = ERR_PTR(-ENOENT);
476
477 clk_data->base = base;
and then some data is written into both `hws` and `base` objects.
Fix this by placing the declaration of object `clk_data` at the end of
`struct stratix10_clock_data`. Also, add a comment to make it clear
that this object must always be last in the structure.
-Wflex-array-member-not-at-end is coming in GCC-14, and we are getting
ready to enable it globally.
Fixes: ba7e258425 ("clk: socfpga: Convert to s10/agilex/n5x to use clk_hw")
Cc: stable@vger.kernel.org
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/1da736106d8e0806aeafa6e471a13ced490eae22.1698117815.git.gustavoars@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The EMAC clocks on Stratix10/Agilex/N5X have an additional bypass that
was not being accounted for. The bypass selects between
emaca_clk/emacb_clk and boot_clk.
Because the bypass register offset is different between Stratix10 and
Agilex/N5X, it's best to create a new function to calculate the bypass.
Fixes: 80c6b7a089 ("clk: socfpga: agilex: add clock driver for the Agilex platform")
Cc: stable@vger.kernel.org
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lore.kernel.org/r/20210611025201.118799-3-dinguyen@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
As recommended by Stephen Boyd, convert the Agilex/Stratix10/n5x clock
driver to use the clk_hw registration method.
Suggested-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lore.kernel.org/r/20210302214151.1333447-3-dinguyen@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Add support for Intel's eASIC N5X platform. The clock manager driver for
the N5X is very similar to the Agilex platform, we can re-use most of
the Agilex clock driver.
This patch makes the necessary changes for the driver to differentiate
between the Agilex and the N5X platforms.
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lore.kernel.org/r/20210212143059.478554-2-dinguyen@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
For the most part the Agilex clock structure is very similar to
Stratix10, so we re-use most of the Stratix10 clock driver.
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lkml.kernel.org/r/20200512181647.5071-5-dinguyen@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Convert, where possible, the stratix10 clock driver to the new parent
data scheme by specifying the parent data for clocks that have multiple
parents.
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lkml.kernel.org/r/20200512181647.5071-1-dinguyen@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Add a clock driver for the Stratix10 SoC. The driver is similar to the
Cyclone5/Arria10 platforms, with the exception that this driver only uses
one single clock binding.
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
