Commit be7a7729 authored by Xin Long's avatar Xin Long Committed by David S. Miller
Browse files

sctp: free cmd->obj.chunk for the unprocessed SCTP_CMD_REPLY 



This patch is to fix a memleak caused by no place to free cmd->obj.chunk
for the unprocessed SCTP_CMD_REPLY. This issue occurs when failing to
process a cmd while there're still SCTP_CMD_REPLY cmds on the cmd seq
with an allocated chunk in cmd->obj.chunk.

So fix it by freeing cmd->obj.chunk for each SCTP_CMD_REPLY cmd left on
the cmd seq when any cmd returns error. While at it, also remove 'nomem'
label.

Reported-by: default avatar <syzbot+107c4aff5f392bf1517f@syzkaller.appspotmail.com>
Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a7869e5f

net/sctp/sm_sideeffect.c

+18 −10
Original line number Diff line number Diff line
@@ -1363,8 +1363,10 @@ static int sctp_cmd_interpreter(enum sctp_event_type event_type, 
			/* Generate an INIT ACK chunk.  */

			new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC,

						     0);

			if (!new_obj)

				goto nomem;

			if (!new_obj) {

				error = -ENOMEM;

				break;

			}



			sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,

					SCTP_CHUNK(new_obj));
@@ -1386,7 +1388,8 @@ static int sctp_cmd_interpreter(enum sctp_event_type event_type, 
			if (!new_obj) {

				if (cmd->obj.chunk)

					sctp_chunk_free(cmd->obj.chunk);

				goto nomem;

				error = -ENOMEM;

				break;

			}

			sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,

					SCTP_CHUNK(new_obj));
@@ -1433,8 +1436,10 @@ static int sctp_cmd_interpreter(enum sctp_event_type event_type, 


			/* Generate a SHUTDOWN chunk.  */

			new_obj = sctp_make_shutdown(asoc, chunk);

			if (!new_obj)

				goto nomem;

			if (!new_obj) {

				error = -ENOMEM;

				break;

			}

			sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,

					SCTP_CHUNK(new_obj));

			break;
@@ -1770,11 +1775,17 @@ static int sctp_cmd_interpreter(enum sctp_event_type event_type, 
			break;

		}



		if (error)

		if (error) {

			cmd = sctp_next_cmd(commands);

			while (cmd) {

				if (cmd->verb == SCTP_CMD_REPLY)

					sctp_chunk_free(cmd->obj.chunk);

				cmd = sctp_next_cmd(commands);

			}

			break;

		}

	}



out:

	/* If this is in response to a received chunk, wait until

	 * we are done with the packet to open the queue so that we don't

	 * send multiple packets in response to a single request.
@@ -1789,7 +1800,4 @@ out: 
		sp->data_ready_signalled = 0;



	return error;

nomem:

	error = -ENOMEM;

	goto out;

}

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