btrfs: use kvcalloc for allocation in btrfs_ioctl_send()

Replace kvzalloc() call with kvcalloc() that also checks the size
internally. There's a standalone overflow check in the function so we
can return invalid parameter combination.  Use array_size() helper to
compute the memory size for clone_sources_tmp.

Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Denis Efremov <efremov@linux.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Denis Efremov 2020-09-21 20:03:36 +03:00 committed by David Sterba
parent 8eb2fd0015
commit bae12df966

View File

@ -7061,7 +7061,7 @@ long btrfs_ioctl_send(struct file *mnt_file, struct btrfs_ioctl_send_args *arg)
u32 i;
u64 *clone_sources_tmp = NULL;
int clone_sources_to_rollback = 0;
unsigned alloc_size;
size_t alloc_size;
int sort_clone_roots = 0;
if (!capable(CAP_SYS_ADMIN))
@ -7147,15 +7147,16 @@ long btrfs_ioctl_send(struct file *mnt_file, struct btrfs_ioctl_send_args *arg)
sctx->waiting_dir_moves = RB_ROOT;
sctx->orphan_dirs = RB_ROOT;
alloc_size = sizeof(struct clone_root) * (arg->clone_sources_count + 1);
sctx->clone_roots = kvzalloc(alloc_size, GFP_KERNEL);
sctx->clone_roots = kvcalloc(sizeof(*sctx->clone_roots),
arg->clone_sources_count + 1,
GFP_KERNEL);
if (!sctx->clone_roots) {
ret = -ENOMEM;
goto out;
}
alloc_size = arg->clone_sources_count * sizeof(*arg->clone_sources);
alloc_size = array_size(sizeof(*arg->clone_sources),
arg->clone_sources_count);
if (arg->clone_sources_count) {
clone_sources_tmp = kvmalloc(alloc_size, GFP_KERNEL);