net: ipa: Annotate struct ipa_power 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 ipa_power.

[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>
Reviewed-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20230922172858.3822653-8-keescook@chromium.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ipa/ipa_power.c b/drivers/net/ipa/ipa_power.c
index 0eaa7a7f33437d94cb7de8042a1b47820e0487b9..e223886123cea91886f3e367c4f7c8fc0819204a 100644 (file)
--- a/drivers/net/ipa/ipa_power.c
+++ b/drivers/net/ipa/ipa_power.c
@@ -67,7 +67,7 @@ struct ipa_power {
        spinlock_t spinlock;    /* used with STOPPED/STARTED power flags */
        DECLARE_BITMAP(flags, IPA_POWER_FLAG_COUNT);
        u32 interconnect_count;
-       struct icc_bulk_data interconnect[];
+       struct icc_bulk_data interconnect[] __counted_by(interconnect_count);
 };
 
 /* Initialize interconnects required for IPA operation */