From 75f5f60bf7ee075ed4a29637ce390898b4c36811 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Mon, 9 Oct 2023 14:44:54 -0600 Subject: btrfs: add __counted_by for struct btrfs_delayed_item and use struct_size() 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 Signed-off-by: Gustavo A. R. Silva Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/delayed-inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/btrfs/delayed-inode.c') diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c index dfe29b29915f..7c2ee0795dc7 100644 --- a/fs/btrfs/delayed-inode.c +++ b/fs/btrfs/delayed-inode.c @@ -313,7 +313,7 @@ static struct btrfs_delayed_item *btrfs_alloc_delayed_item(u16 data_len, { 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; -- cgit v1.2.3