6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
commit 02fb4f0084331ef72c28d0c70fcb15d1bea369ec upstream.
Flexible-array member `hws` in `struct clk_hw_onecell_data` is annotated
with the `counted_by()` attribute. This means that when memory is
allocated for this array, the _counter_, which in this case is member
`num` in the flexible structure, should be set to the maximum number of
elements the flexible array can contain, or fewer.
In this case, the total number of elements for the flexible array is
determined by variable `clks_num` when allocating heap space via
`devm_kzalloc()`, as shown below:
289 struct loongson2_clk_provider *clp;
...
296 for (p = data; p->name; p++)
297 clks_num++;
298
299 clp = devm_kzalloc(dev, struct_size(clp, clk_data.hws, clks_num),
300 GFP_KERNEL);
So, `clp->clk_data.num` should be set to `clks_num` or less, and not
exceed `clks_num`, as is currently the case. Otherwise, if data is
written into `clp->clk_data.hws[clks_num]`, the instrumentation
provided by the compiler won't detect the overflow, leading to a
memory corruption bug at runtime.
Fix this issue by setting `clp->clk_data.num` to `clks_num`.
Fixes: 9796ec0bd04b ("clk: clk-loongson2: Refactor driver for adding new platforms")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
Link: https://lore.kernel.org/r/ZzaN5MpmMr0hwHw9@kspp
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/clk/clk-loongson2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/clk/clk-loongson2.c
+++ b/drivers/clk/clk-loongson2.c
@@ -306,7 +306,7 @@ static int loongson2_clk_probe(struct pl
return PTR_ERR(clp->base);
spin_lock_init(&clp->clk_lock);
- clp->clk_data.num = clks_num + 1;
+ clp->clk_data.num = clks_num;
clp->dev = dev;
for (i = 0; i < clks_num; i++) {
