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 via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
While there, use struct_size() helper, instead of the open-coded
version, to calculate the size for the allocation of the whole
flexible structure, including of course, the flexible-array member.
This code was found with the help of Coccinelle, and audited and
fixed manually.
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
{
struct btrfs_delayed_item *item;
- item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
+ item = kmalloc(struct_size(item, data, data_len), GFP_NOFS);
if (item) {
item->data_len = data_len;
item->type = type;
bool logged;
/* The maximum leaf size is 64K, so u16 is more than enough. */
u16 data_len;
- char data[];
+ char data[] __counted_by(data_len);
};
static inline void btrfs_init_delayed_root(