Revision 16:a61070aa2e98, committed 2014-04-10

Comitter:

donatien

Date:

Thu Apr 10 17:37:32 2014 +0000

Parent:

15:e5bb25d5506f

Commit message:

Fixed race condition in PPP

Changed in this revision

diff -r e5bb25d5506f -r a61070aa2e98 netif/ppp/ppp.c
--- a/netif/ppp/ppp.c	Wed Mar 12 20:22:30 2014 +0000
+++ b/netif/ppp/ppp.c	Thu Apr 10 17:37:32 2014 +0000
@@ -252,6 +252,7 @@
 
 static PPPControl pppControl[NUM_PPP] __attribute((section("AHBSRAM1"))); /* The PPP interface control blocks. */
 
+static sys_mutex_t pppMtx; //Used to prevent concurrent access from user thread (pppStop) and input thread (pppInproc)
 static sys_mbox_t pppMboxStart; //Used to signal PPP thread that a PPP session begins
 static sys_mbox_t pppMboxStopped; //Used to signal remote thread that a PPP session has stopped
 
@@ -449,6 +450,7 @@
 
   subnetMask = PP_HTONL(0xffffff00UL);
 
+  sys_mutex_new(&pppMtx);
   sys_mbox_new(&pppMboxStart, 1);
   sys_mbox_new(&pppMboxStopped, 1);
   
@@ -662,7 +664,9 @@
   int st = 0;
 
   PPPDEBUG(LOG_DEBUG, ("pppClose() called\n"));
-
+  
+  sys_mutex_lock(&pppMtx);
+  
   /* Disconnect */
 #if PPPOE_SUPPORT
   if(pc->ethif) {
@@ -681,6 +685,8 @@
     pppRecvWakeup(pd);
 #endif /* PPPOS_SUPPORT */
   }
+  
+  sys_mutex_unlock(&pppMtx);
 
   void* pcrx;
   sys_arch_mbox_fetch(&pppMboxStopped, (void**)&pcrx, 0); //Wait indefinitely for link to become dead
@@ -1525,7 +1531,9 @@
     while (lcp_phase[pcrx->pd] != PHASE_DEAD) {
       count = sio_read(pcrx->fd, pcrx->rxbuf, PPPOS_RX_BUFSIZE);
       if(count > 0) {
+        sys_mutex_lock(&pppMtx);
         pppInProc(pcrx, pcrx->rxbuf, count);
+        sys_mutex_unlock(&pppMtx);
       } else {
         /* nothing received, give other tasks a chance to run */
         sys_msleep(1);