skb_copy_datagram_iovec() can die (d3a9632f) · Commits · e / devices / android_kernel_fairphone_FP4

include/linux/skbuff.h

+0 −2

Original line number	Diff line number	Diff line
		@@ -2644,8 +2644,6 @@ struct sk_buff skb_recv_datagram(struct sock sk, unsigned flags, int noblock,
		int *err);
		unsigned int datagram_poll(struct file file, struct socket sock,
		struct poll_table_struct *wait);
		int skb_copy_datagram_iovec(const struct sk_buff *from, int offset,
		struct iovec *to, int size);
		int skb_copy_datagram_iter(const struct sk_buff *from, int offset,
		struct iov_iter *to, int size);
		static inline int skb_copy_datagram_msg(const struct sk_buff *from, int offset,

net/core/datagram.c

+0 −84

Original line number	Diff line number	Diff line
		@@ -309,90 +309,6 @@ int skb_kill_datagram(struct sock sk, struct sk_buff skb, unsigned int flags)
		}
		EXPORT_SYMBOL(skb_kill_datagram);

		/**
		* skb_copy_datagram_iovec - Copy a datagram to an iovec.
		* @skb: buffer to copy
		* @offset: offset in the buffer to start copying from
		* @to: io vector to copy to
		* @len: amount of data to copy from buffer to iovec
		*
		* Note: the iovec is modified during the copy.
		*/
		int skb_copy_datagram_iovec(const struct sk_buff *skb, int offset,
		struct iovec *to, int len)
		{
		int start = skb_headlen(skb);
		int i, copy = start - offset;
		struct sk_buff *frag_iter;

		trace_skb_copy_datagram_iovec(skb, len);

		/* Copy header. */
		if (copy > 0) {
		if (copy > len)
		copy = len;
		if (memcpy_toiovec(to, skb->data + offset, copy))
		goto fault;
		if ((len -= copy) == 0)
		return 0;
		offset += copy;
		}

		/* Copy paged appendix. Hmm... why does this look so complicated? */
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		int end;
		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];

		WARN_ON(start > offset + len);

		end = start + skb_frag_size(frag);
		if ((copy = end - offset) > 0) {
		int err;
		u8 *vaddr;
		struct page *page = skb_frag_page(frag);

		if (copy > len)
		copy = len;
		vaddr = kmap(page);
		err = memcpy_toiovec(to, vaddr + frag->page_offset +
		offset - start, copy);
		kunmap(page);
		if (err)
		goto fault;
		if (!(len -= copy))
		return 0;
		offset += copy;
		}
		start = end;
		}

		skb_walk_frags(skb, frag_iter) {
		int end;

		WARN_ON(start > offset + len);

		end = start + frag_iter->len;
		if ((copy = end - offset) > 0) {
		if (copy > len)
		copy = len;
		if (skb_copy_datagram_iovec(frag_iter,
		offset - start,
		to, copy))
		goto fault;
		if ((len -= copy) == 0)
		return 0;
		offset += copy;
		}
		start = end;
		}
		if (!len)
		return 0;

		fault:
		return -EFAULT;
		}
		EXPORT_SYMBOL(skb_copy_datagram_iovec);

		/**
		* skb_copy_datagram_iter - Copy a datagram to an iovec iterator.
		* @skb: buffer to copy