| Message ID | ZNvimeRAPkJ24zRG@work (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [next] RDMA/mlx4: Copy union directly | expand |
On Tue, Aug 15, 2023 at 02:39:53PM -0600, Gustavo A. R. Silva wrote: > Copy union directly instead of using memcpy(). > > Note that in this case, a direct assignment is more readable and > consistent with the subsequent assignments. > > This addresses the following -Wstringop-overflow warning seen in s390 > with defconfig: > drivers/infiniband/hw/mlx4/main.c:296:33: warning: writing 16 bytes into a region of size 0 [-Wstringop-overflow=] > 296 | memcpy(&port_gid_table->gids[free].gid, > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > 297 | &attr->gid, sizeof(attr->gid)); > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Hm, why did it think the union had a size of 0? Regardless, it's a nice fix: Reviewed-by: Kees Cook <keescook@chromium.org>
On Tue, 15 Aug 2023 14:39:53 -0600, Gustavo A. R. Silva wrote: > Copy union directly instead of using memcpy(). > > Note that in this case, a direct assignment is more readable and > consistent with the subsequent assignments. > > This addresses the following -Wstringop-overflow warning seen in s390 > with defconfig: > drivers/infiniband/hw/mlx4/main.c:296:33: warning: writing 16 bytes into a region of size 0 [-Wstringop-overflow=] > 296 | memcpy(&port_gid_table->gids[free].gid, > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > 297 | &attr->gid, sizeof(attr->gid)); > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > [...] Applied, thanks! [1/1] RDMA/mlx4: Copy union directly https://git.kernel.org/rdma/rdma/c/18ddaeb03bdb65 Best regards,
diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c index 216aacd72e4f..2d2cd17e02e6 100644 --- a/drivers/infiniband/hw/mlx4/main.c +++ b/drivers/infiniband/hw/mlx4/main.c @@ -293,8 +293,7 @@ static int mlx4_ib_add_gid(const struct ib_gid_attr *attr, void **context) ret = -ENOMEM; } else { *context = port_gid_table->gids[free].ctx; - memcpy(&port_gid_table->gids[free].gid, - &attr->gid, sizeof(attr->gid)); + port_gid_table->gids[free].gid = attr->gid; port_gid_table->gids[free].gid_type = attr->gid_type; port_gid_table->gids[free].vlan_id = vlan_id; port_gid_table->gids[free].ctx->real_index = free;
Copy union directly instead of using memcpy(). Note that in this case, a direct assignment is more readable and consistent with the subsequent assignments. This addresses the following -Wstringop-overflow warning seen in s390 with defconfig: drivers/infiniband/hw/mlx4/main.c:296:33: warning: writing 16 bytes into a region of size 0 [-Wstringop-overflow=] 296 | memcpy(&port_gid_table->gids[free].gid, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 297 | &attr->gid, sizeof(attr->gid)); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This helps with the ongoing efforts to globally enable -Wstringop-overflow. Link: https://github.com/KSPP/linux/issues/308 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- drivers/infiniband/hw/mlx4/main.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)