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From:   Kees Cook <keescook@chromium.org>
To:     Sebastian Reichel <sre@kernel.org>
Cc:     Kees Cook <keescook@chromium.org>, Chen-Yu Tsai <wens@csie.org>,
        linux-pm@vger.kernel.org, Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev, linux-hardening@vger.kernel.org
Subject: [PATCH] power: supply: axp20x_usb_power: Annotate struct axp20x_usb_power with __counted_by
Date:   Fri, 22 Sep 2023 10:53:58 -0700
Message-Id: <20230922175358.work.774-kees@kernel.org>
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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 axp20x_usb_power.

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

Cc: Sebastian Reichel <sre@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 drivers/power/supply/axp20x_usb_power.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/power/supply/axp20x_usb_power.c b/drivers/power/supply/axp20x_usb_power.c
index bde17406c130..e23308ad4cc7 100644
--- a/drivers/power/supply/axp20x_usb_power.c
+++ b/drivers/power/supply/axp20x_usb_power.c
@@ -73,7 +73,7 @@ struct axp20x_usb_power {
 	unsigned int old_status;
 	unsigned int online;
 	unsigned int num_irqs;
-	unsigned int irqs[];
+	unsigned int irqs[] __counted_by(num_irqs);
 };
 
 static bool axp20x_usb_vbus_needs_polling(struct axp20x_usb_power *power)
-- 
2.34.1