Instead of using large buffers in imsgs, add the data or path onto the end.

1 files changed, 38 insertions, 25 deletions

diff --git a/usr.bin/tmux/file.c b/usr.bin/tmux/file.c
index 7a32b24acdd..c7d68fecf7b 100644
--- a/usr.bin/tmux/file.c
+++ b/usr.bin/tmux/file.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: file.c,v 1.2 2019/12/12 11:51:32 nicm Exp $ */
+/* $OpenBSD: file.c,v 1.3 2019/12/16 15:48:50 nicm Exp $ */
 
 /*
  * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -17,9 +17,11 @@
  */
 
 #include <sys/types.h>
+#include <sys/queue.h>
 
 #include <errno.h>
 #include <fcntl.h>
+#include <imsg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -147,7 +149,6 @@ file_vprint(struct client *c, const char *fmt, va_list ap)
 		msg.stream = 1;
 		msg.fd = STDOUT_FILENO;
 		msg.flags = 0;
-		strlcpy(msg.path, "-", sizeof msg.path);
 		proc_send(c->peer, MSG_WRITE_OPEN, -1, &msg, sizeof msg);
 	} else {
 		evbuffer_add_vprintf(cf->buffer, fmt, ap);
@@ -174,7 +175,6 @@ file_print_buffer(struct client *c, void *data, size_t size)
 		msg.stream = 1;
 		msg.fd = STDOUT_FILENO;
 		msg.flags = 0;
-		strlcpy(msg.path, "-", sizeof msg.path);
 		proc_send(c->peer, MSG_WRITE_OPEN, -1, &msg, sizeof msg);
 	} else {
 		evbuffer_add(cf->buffer, data, size);
@@ -204,7 +204,6 @@ file_error(struct client *c, const char *fmt, ...)
 		msg.stream = 2;
 		msg.fd = STDERR_FILENO;
 		msg.flags = 0;
-		strlcpy(msg.path, "-", sizeof msg.path);
 		proc_send(c->peer, MSG_WRITE_OPEN, -1, &msg, sizeof msg);
 	} else {
 		evbuffer_add_vprintf(cf->buffer, fmt, ap);
@@ -220,7 +219,8 @@ file_write(struct client *c, const char *path, int flags, const void *bdata,
 {
 	struct client_file	*cf;
 	FILE			*f;
-	struct msg_write_open	 msg;
+	struct msg_write_open	*msg;
+	size_t			 msglen;
 	int			 fd = -1;
 	const char		*mode;
 
@@ -261,17 +261,22 @@ file_write(struct client *c, const char *path, int flags, const void *bdata,
 skip:
 	evbuffer_add(cf->buffer, bdata, bsize);
 
-	msg.stream = cf->stream;
-	msg.fd = fd;
-	msg.flags = flags;
-	if (strlcpy(msg.path, cf->path, sizeof msg.path) >= sizeof msg.path) {
+	msglen = strlen(cf->path) + 1 + sizeof *msg;
+	if (msglen > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
 		cf->error = E2BIG;
 		goto done;
 	}
-	if (proc_send(c->peer, MSG_WRITE_OPEN, -1, &msg, sizeof msg) != 0) {
+	msg = xmalloc(msglen);
+	msg->stream = cf->stream;
+	msg->fd = fd;
+	msg->flags = flags;
+	memcpy(msg + 1, cf->path, msglen - sizeof *msg);
+	if (proc_send(c->peer, MSG_WRITE_OPEN, -1, msg, msglen) != 0) {
+		free(msg);
 		cf->error = EINVAL;
 		goto done;
 	}
+	free(msg);
 	return;
 
 done:
@@ -283,10 +288,10 @@ file_read(struct client *c, const char *path, client_file_cb cb, void *cbdata)
 {
 	struct client_file	*cf;
 	FILE			*f;
-	struct msg_read_open	 msg;
+	struct msg_read_open	*msg;
+	size_t			 msglen, size;
 	int			 fd = -1;
 	char			 buffer[BUFSIZ];
-	size_t			 size;
 
 	if (strcmp(path, "-") == 0) {
 		cf = file_create(c, file_next_stream++, cb, cbdata);
@@ -327,16 +332,21 @@ file_read(struct client *c, const char *path, client_file_cb cb, void *cbdata)
 	}
 
 skip:
-	msg.stream = cf->stream;
-	msg.fd = fd;
-	if (strlcpy(msg.path, cf->path, sizeof msg.path) >= sizeof msg.path) {
+	msglen = strlen(cf->path) + 1 + sizeof *msg;
+	if (msglen > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
 		cf->error = E2BIG;
 		goto done;
 	}
-	if (proc_send(c->peer, MSG_READ_OPEN, -1, &msg, sizeof msg) != 0) {
+	msg = xmalloc(msglen);
+	msg->stream = cf->stream;
+	msg->fd = fd;
+	memcpy(msg + 1, cf->path, msglen - sizeof *msg);
+	if (proc_send(c->peer, MSG_READ_OPEN, -1, msg, msglen) != 0) {
+		free(msg);
 		cf->error = EINVAL;
 		goto done;
 	}
+	free(msg);
 	return;
 
 done:
@@ -358,20 +368,22 @@ void
 file_push(struct client_file *cf)
 {
 	struct client		*c = cf->c;
-	struct msg_write_data	 msg;
+	struct msg_write_data	*msg;
+	size_t			 msglen, sent, left;
 	struct msg_write_close	 close;
-	size_t			 sent, left;
 
+	msg = xmalloc(sizeof *msg);
 	left = EVBUFFER_LENGTH(cf->buffer);
 	while (left != 0) {
 		sent = left;
-		if (sent > sizeof msg.data)
-			sent = sizeof msg.data;
-		memcpy(msg.data, EVBUFFER_DATA(cf->buffer), sent);
-		msg.size = sent;
-
-		msg.stream = cf->stream;
-		if (proc_send(c->peer, MSG_WRITE, -1, &msg, sizeof msg) != 0)
+		if (sent > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
+			sent = MAX_IMSGSIZE - IMSG_HEADER_SIZE;
+
+		msglen = (sizeof *msg) + sent;
+		msg = xrealloc(msg, msglen);
+		msg->stream = cf->stream;
+		memcpy(msg + 1, EVBUFFER_DATA(cf->buffer), sent);
+		if (proc_send(c->peer, MSG_WRITE, -1, msg, msglen) != 0)
 			break;
 		evbuffer_drain(cf->buffer, sent);
 
@@ -387,4 +399,5 @@ file_push(struct client_file *cf)
 		proc_send(c->peer, MSG_WRITE_CLOSE, -1, &close, sizeof close);
 		file_fire_done(cf);
 	}
+	free(msg);
 }