clk: bcm: dvp: Assign ->num before accessing ->hws

Commit f316cdf ("clk: Annotate struct clk_hw_onecell_data with
__counted_by") annotated the hws member of 'struct clk_hw_onecell_data'
with __counted_by, which informs the bounds sanitizer about the number
of elements in hws, so that it can warn when hws is accessed out of
bounds. As noted in that change, the __counted_by member must be
initialized with the number of elements before the first array access
happens, otherwise there will be a warning from each access prior to the
initialization because the number of elements is zero. This occurs in
clk_dvp_probe() due to ->num being assigned after ->hws has been
accessed:

  UBSAN: array-index-out-of-bounds in drivers/clk/bcm/clk-bcm2711-dvp.c:59:2
  index 0 is out of range for type 'struct clk_hw *[] __counted_by(num)' (aka 'struct clk_hw *[]')

Move the ->num initialization to before the first access of ->hws, which
clears up the warning.

Cc: [email protected]
Fixes: f316cdf ("clk: Annotate struct clk_hw_onecell_data with __counted_by")
Signed-off-by: Nathan Chancellor <[email protected]>
Link: https://lore.kernel.org/r/20240425-cbl-bcm-assign-counted-by-val-before-access-v1-1-e2db3b82d5ef@kernel.org
Reviewed-by: Kees Cook <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
Signed-off-by: Stephen Boyd <[email protected]>

Author: nathanchance

drivers/clk/bcm/clk-bcm2711-dvp.c

@@ -56,6 +56,8 @@ static int clk_dvp_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	data->num = NR_CLOCKS;
+
 	data->hws[0] = clk_hw_register_gate_parent_data(&pdev->dev,
 							"hdmi0-108MHz",
 							&clk_dvp_parent, 0,
@@ -76,7 +78,6 @@ static int clk_dvp_probe(struct platform_device *pdev)
 		goto unregister_clk0;
 	}
 
-	data->num = NR_CLOCKS;
 	ret = of_clk_add_hw_provider(pdev->dev.of_node, of_clk_hw_onecell_get,
 				     data);
 	if (ret)