IB/srp: Annotate struct srp_fr_pool 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 srp_fr_pool.

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

Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230929180431.3005464-5-keescook@chromium.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>

diff --git a/drivers/infiniband/ulp/srp/ib_srp.h b/drivers/infiniband/ulp/srp/ib_srp.h
index 5d94db453df322abfe9496f6b9f24076a45b2bdd..349576ff384506cabacbb3a35ba6ed771330d2ef 100644 (file)
--- a/drivers/infiniband/ulp/srp/ib_srp.h
+++ b/drivers/infiniband/ulp/srp/ib_srp.h
@@ -306,7 +306,7 @@ struct srp_fr_pool {
        int                     max_page_list_len;
        spinlock_t              lock;
        struct list_head        free_list;
-       struct srp_fr_desc      desc[];
+       struct srp_fr_desc      desc[] __counted_by(size);
 };
 
 /**