Re: [PATCH] interconnect: Annotate struct icc_path with __counted_by

From: Gustavo A. R. Silva
Date: Thu Aug 17 2023 - 17:01:40 EST




On 8/17/23 14:41, 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 icc_path.

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

Cc: Georgi Djakov <djakov@xxxxxxxxxx>
Cc: linux-pm@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

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

Thanks
--
Gustavo

---
drivers/interconnect/internal.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/interconnect/internal.h b/drivers/interconnect/internal.h
index f5f82a5c939e..b30856db523d 100644
--- a/drivers/interconnect/internal.h
+++ b/drivers/interconnect/internal.h
@@ -38,7 +38,7 @@ struct icc_req {
struct icc_path {
const char *name;
size_t num_nodes;
- struct icc_req reqs[];
+ struct icc_req reqs[] __counted_by(num_nodes);
};
#endif