From: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
commit 8d1b73dd25ff92c3fa9807a20c22fa2b44c07336 upstream.
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 module_sect_attrs {
...
struct module_sect_attr attrs[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(*sect_attrs) + nloaded * sizeof(sect_attrs->attrs[0]
with:
struct_size(sect_attrs, attrs, nloaded)
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
Signed-off-by: Jessica Yu <jeyu@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/module.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1491,8 +1491,7 @@ static void add_sect_attrs(struct module
for (i = 0; i < info->hdr->e_shnum; i++)
if (!sect_empty(&info->sechdrs[i]))
nloaded++;
- size[0] = ALIGN(sizeof(*sect_attrs)
- + nloaded * sizeof(sect_attrs->attrs[0]),
+ size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded),
sizeof(sect_attrs->grp.attrs[0]));
size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
