One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:
struct msm_gem_submit {
...
struct {
...
} bos[0];
};
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.
So, replace the following form:
sizeof(*submit) + ((u64)nr_bos * sizeof(submit->bos[0]))
with:
struct_size(submit, bos, nr_bos)
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/msm/msm_gem_submit.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index 348f8c2be806..7c17c6154058 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -26,8 +26,8 @@ static struct msm_gem_submit *submit_create(struct drm_device *dev,
uint32_t nr_cmds)
{
struct msm_gem_submit *submit;
- uint64_t sz = sizeof(*submit) + ((u64)nr_bos * sizeof(submit->bos[0])) +
- ((u64)nr_cmds * sizeof(submit->cmd[0]));
+ uint64_t sz = struct_size(submit, bos, nr_bos) +
+ ((u64)nr_cmds * sizeof(submit->cmd[0]));
if (sz > SIZE_MAX)
return NULL;
--
2.22.0
