[Pcsclite-cvs-commit] r3446 - /trunk/PCSC/src/winscard_clnt.c

[rousseau at users.alioth.debian.org]

Author: rousseau
Date: Tue Apr 14 09:24:47 2009
New Revision: 3446

URL: http://svn.debian.org/wsvn/pcsclite/?sc=1&rev=3446
Log:
WaitForPcscdEvent(): avoid a possible crash due to a race condition

Thanks to Matheus Ribeiro for the patch

Modified:
    trunk/PCSC/src/winscard_clnt.c

Modified: trunk/PCSC/src/winscard_clnt.c
URL: http://svn.debian.org/wsvn/pcsclite/trunk/PCSC/src/winscard_clnt.c?rev=3446&op=diff
==============================================================================
--- trunk/PCSC/src/winscard_clnt.c (original)
+++ trunk/PCSC/src/winscard_clnt.c Tue Apr 14 09:24:47 2009
@@ -1743,13 +1743,18 @@
 	(void)mkfifo(filename, 0644);
 	fd = SYS_OpenFile(filename, O_RDONLY | O_NONBLOCK, 0);
 
-	FD_ZERO(&read_fd);
-	FD_SET(fd, &read_fd);
-	
-	(void)select(fd+1, &read_fd, NULL, NULL, ptv);
-
-	(void)SYS_ReadFile(fd, buf, 1);
-	(void)SYS_CloseFile(fd);
+	/* the file may have been removed between the mkfifo() and open() */
+	if (-1 != fd)
+	{
+		FD_ZERO(&read_fd);
+		FD_SET(fd, &read_fd);
+		
+		(void)select(fd+1, &read_fd, NULL, NULL, ptv);
+
+		(void)SYS_ReadFile(fd, buf, 1);
+		(void)SYS_CloseFile(fd);
+	}
+
 	(void)SYS_RemoveFile(filename);
 
 	if (INFINITE != dwTime)