Re: [PATCH] irqdomain: Annotate struct irq_domain with __counted_by

From: Gustavo A. R. Silva
Date: Sat Sep 23 2023 - 11:02:18 EST




On 9/22/23 11:51, Kees Cook wrote:
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 irq_domain.

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

Cc: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

Thanks
--
Gustavo

---
include/linux/irqdomain.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 51c254b7fec2..ee0a82c60508 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -174,7 +174,7 @@ struct irq_domain {
irq_hw_number_t hwirq_max;
unsigned int revmap_size;
struct radix_tree_root revmap_tree;
- struct irq_data __rcu *revmap[];
+ struct irq_data __rcu *revmap[] __counted_by(revmap_size);
};
/* Irq domain flags */