bus: vexpress-config: Annotate struct vexpress_syscfg_func with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions).

As found with Coccinelle[1], add __counted_by for struct vexpress_syscfg_func.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc Liviu Dudau <[email protected]>

Cc Sudeep Holla <[email protected]>

Cc Lorenzo Pieralisi <[email protected]>

Cc Rob Herring <[email protected]>

Cc Yangtao Li <[email protected]>

Cc [email protected]

Signed-off-by Kees Cook <[email protected]>

---
  drivers/bus/vexpress-config.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

drivers/bus/vexpress-config.c +1 -1

index c4e1becbb2d2..d2c7ada90186 100644
@@ -54,7 +54,7 @@ struct vexpress_syscfg_func {
  	struct vexpress_syscfg *syscfg;
  	struct regmap *regmap;
  	int num_templates;
-	u32 template[]; /* Keep it last! */
+	u32 template[] __counted_by(num_templates); /* Keep it last! */
  };
 
  struct vexpress_config_bridge_ops {

Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions).

As found with Coccinelle[1], add __counted_by for struct vexpress_syscfg_func.

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