[PATCH 07/12] igb: Proactively round up to kmalloc bucket size

Kees Cook
2022-09-22T03:10:28Z

Instead of having a mismatch between the requested allocation size and
the actual kmalloc bucket size, which is examined later via ksize(),
round up proactively so the allocation is explicitly made for the full
size, allowing the compiler to correctly reason about the resulting size
of the buffer through the existing __alloc_size() hint.

Cc: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: Tony Nguyen <anthony.l.nguyen@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: intel-wired-lan@lists.osuosl.org
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
drivers/net/ethernet/intel/igb/igb_main.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index 2796e81d2726..4d70ee5b0f79 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -1196,6 +1196,7 @@ static int igb_alloc_q_vector(struct igb_adapter *adapter,

ring_count = txr_count + rxr_count;
size = struct_size(q_vector, ring, ring_count);
+ size = kmalloc_size_roundup(size);

/* allocate q_vector and rings */
q_vector = adapter->q_vector[v_idx];
--
2.34.1