Re: [PATCH] mfd: iqs62x: Annotate struct iqs62x_fw_blk with __counted_by

From: Gustavo A. R. Silva
Date: Sat Sep 23 2023 - 21:58:58 EST




On 9/22/23 11:53, 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 iqs62x_fw_blk.

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

Cc: Lee Jones <lee@xxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

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

Thanks
--
Gustavo

---
drivers/mfd/iqs62x.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mfd/iqs62x.c b/drivers/mfd/iqs62x.c
index e03b4d38fbb0..1b465590567c 100644
--- a/drivers/mfd/iqs62x.c
+++ b/drivers/mfd/iqs62x.c
@@ -96,7 +96,7 @@ struct iqs62x_fw_blk {
u8 addr;
u8 mask;
u8 len;
- u8 data[];
+ u8 data[] __counted_by(len);
};
struct iqs62x_info {