mISDN: Add allocation of recvbuf[1500] at run time to reduce stack size

Before: 1656 bytes on i386, now 164.
Modified by Andreas Eversberg <andreas@eversberg.eu>

Signed-off-by: Frank Seidel <frank@f-seidel.de>
Signed-off-by: Andreas Eversberg <andreas@eversberg.eu>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 4 deletions

diff --git a/drivers/isdn/mISDN/l1oip_core.c b/drivers/isdn/mISDN/l1oip_core.c
index abe574989572..ea3c3aa2004b 100644
--- a/drivers/isdn/mISDN/l1oip_core.c
+++ b/drivers/isdn/mISDN/l1oip_core.c
@@ -663,18 +663,28 @@ l1oip_socket_thread(void *data)
         struct iovec iov;
         mm_segment_t oldfs;
         struct sockaddr_in sin_rx;
-        unsigned char recvbuf[1500];
+        unsigned char *recvbuf;
+        size_t recvbuf_size = 1500;
         int recvlen;
         struct socket *socket = NULL;
         DECLARE_COMPLETION(wait);
 
+        /* allocate buffer memory */
+        recvbuf = kmalloc(recvbuf_size, GFP_KERNEL);
+        if (!recvbuf) {
+                printk(KERN_ERR "%s: Failed to alloc recvbuf.\n", __func__);
+                ret = -ENOMEM;
+                goto fail;
+        }
+
         /* make daemon */
         allow_signal(SIGTERM);
 
         /* create socket */
         if (sock_create(PF_INET, SOCK_DGRAM, IPPROTO_UDP, &socket)) {
                 printk(KERN_ERR "%s: Failed to create socket.\n", __func__);
-                return -EIO;
+                ret = -EIO;
+                goto fail;
         }
 
         /* set incoming address */
@@ -730,10 +740,10 @@ l1oip_socket_thread(void *data)
                         __func__);
         while (!signal_pending(current)) {
                 iov.iov_base = recvbuf;
-                iov.iov_len = sizeof(recvbuf);
+                iov.iov_len = recvbuf_size;
                 oldfs = get_fs();
                 set_fs(KERNEL_DS);
-                recvlen = sock_recvmsg(socket, &msg, sizeof(recvbuf), 0);
+                recvlen = sock_recvmsg(socket, &msg, recvbuf_size, 0);
                 set_fs(oldfs);
                 if (recvlen > 0) {
                         l1oip_socket_parse(hc, &sin_rx, recvbuf, recvlen);
@@ -760,6 +770,9 @@ l1oip_socket_thread(void *data)
                         __func__);
 
 fail:
+        /* free recvbuf */
+        kfree(recvbuf);
+
         /* close socket */
         if (socket)
                 sock_release(socket);