From: Kees Cook <keescook@chromium.org>
Date: Fri, 22 Sep 2023 17:51:55 +0000 (-0700)
Subject: eeprom: at24: Annotate struct at24_data with __counted_by
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=997a29bbb1e0d6d10ebc2291fac604c4cded5828;p=linux.git

eeprom: at24: Annotate struct at24_data 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 at24_data.

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

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---

diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index af83aca452b76..7dfd7fdb423e6 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -92,7 +92,7 @@ struct at24_data {
 	 * them for us.
 	 */
 	u8 bank_addr_shift;
-	struct regmap *client_regmaps[];
+	struct regmap *client_regmaps[] __counted_by(num_addresses);
 };
 
 /*