Commit 1ec9daf9 authored by Matthew Wood's avatar Matthew Wood Committed by David S. Miller
Browse files

net: netconsole: append userdata to fragmented netconsole messages 



Regardless of whether the original message body or formatted userdata
exceeds the MAX_PRINT_CHUNK, append userdata to the netconsole message
starting with the first chunk that has available space after writing the
body.

Co-developed-by: default avatarBreno Leitao <leitao@debian.org>
Signed-off-by: default avatarBreno Leitao <leitao@debian.org>
Signed-off-by: default avatarMatthew Wood <thepacketgeek@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent b4ab4f2c

drivers/net/netconsole.c

+37 −13
Original line number Diff line number Diff line
@@ -1085,24 +1085,48 @@ static void send_ext_msg_udp(struct netconsole_target *nt, const char *msg, 
	memcpy(buf + release_len, header, header_len);

	header_len += release_len;



	while (offset < body_len) {

	while (offset < body_len + userdata_len) {

		int this_header = header_len;

		int this_chunk;

		int this_offset = 0;

		int this_chunk = 0;



		this_header += scnprintf(buf + this_header,

					 sizeof(buf) - this_header,

					 ",ncfrag=%d/%d;", offset, body_len);

					 ",ncfrag=%d/%d;", offset,

					 body_len + userdata_len);



		/* Not all body data has been written yet */

		if (offset < body_len) {

			this_chunk = min(body_len - offset,

					 MAX_PRINT_CHUNK - this_header);

			if (WARN_ON_ONCE(this_chunk <= 0))

				return;



			memcpy(buf + this_header, body + offset, this_chunk);

			this_offset += this_chunk;

		}

		/* Body is fully written and there is pending userdata to write,

		 * append userdata in this chunk

		 */

		if (offset + this_offset >= body_len &&

		    offset + this_offset < userdata_len + body_len) {

			int sent_userdata = (offset + this_offset) - body_len;

			int preceding_bytes = this_chunk + this_header;



			if (WARN_ON_ONCE(sent_userdata < 0))

				return;



		netpoll_send_udp(&nt->np, buf, this_header + this_chunk);

			this_chunk = min(userdata_len - sent_userdata,

					 MAX_PRINT_CHUNK - preceding_bytes);

			if (WARN_ON_ONCE(this_chunk <= 0))

				return;

			memcpy(buf + this_header + this_offset,

			       userdata + sent_userdata,

			       this_chunk);

			this_offset += this_chunk;

		}



		offset += this_chunk;

		netpoll_send_udp(&nt->np, buf, this_header + this_offset);

		offset += this_offset;

	}

}