[Ocfs2-devel] [Patch 2/3] ocfs2-tools: ocfs2_controld leaves std(in|out|err) unassigned

[Ocfs2-devel] [Patch 2/3] ocfs2-tools: ocfs2_controld leaves std(in|out|err) unassigned

[Andrew Beekhof]

Leaving std(in|out|err) unassigned causes havoc when included code (in  
this case openais libraries) print to std(err|out).
Specifically, this often leads to memory corruption since the output  
is sent to IPC sockets.

The safest approach is to reopen std(in|out|err) and have them point  
to /dev/null

Signed-off-by: Andrew Beekhof <abeekhof@suse.de>

--- upstream/ocfs2_controld/main.c	2008-10-27 14:55:50.000000000 +0100
+++ dev/ocfs2_controld/main.c	2008-10-27 14:57:24.000000000 +0100
@@ -1027,6 +1027,7 @@ static void lockfile(void)

  static void daemonize(void)
  {
+	int fd;
  	pid_t pid = fork();
  	if (pid < 0) {
  		perror("main: cannot fork");
@@ -1040,6 +1041,18 @@ static void daemonize(void)
  	close(0);
  	close(1);
  	close(2);
+	fd = open("/dev/null", O_RDWR);
+	if (fd >= 0) {
+		/* dup2 to 0 / 1 / 2 (stdin / stdout / stderr) */
+		dup2(fd, STDIN_FILENO);  /* 0 */
+		dup2(fd, STDOUT_FILENO); /* 1 */
+		dup2(fd, STDERR_FILENO); /* 2 */
+
+		/* Should be 0, but just in case it isn't... */
+		if (fd > 2) {
+			close(fd);
+		}
+	}
  	openlog("ocfs2_controld", LOG_PID, LOG_DAEMON);

  	lockfile();

[Ocfs2-devel] [Patch 2/3] ocfs2-tools: ocfs2_controld leaves std(in|out|err) unassigned

[Joel Becker]

On Tue, Nov 18, 2008 at 11:18:42AM +0100, Andrew Beekhof wrote:
> Leaving std(in|out|err) unassigned causes havoc when included code (in  
> this case openais libraries) print to std(err|out).
> Specifically, this often leads to memory corruption since the output  
> is sent to IPC sockets.
> 
> The safest approach is to reopen std(in|out|err) and have them point  
> to /dev/null
> 
> Signed-off-by: Andrew Beekhof <abeekhof@suse.de>
Signed-off-by: Joel Becker <joel.becker@oracle.com>

> 
> --- upstream/ocfs2_controld/main.c	2008-10-27 14:55:50.000000000 +0100
> +++ dev/ocfs2_controld/main.c	2008-10-27 14:57:24.000000000 +0100
> @@ -1027,6 +1027,7 @@ static void lockfile(void)
> 
>   static void daemonize(void)
>   {
> +	int fd;
>   	pid_t pid = fork();
>   	if (pid < 0) {
>   		perror("main: cannot fork");
> @@ -1040,6 +1041,18 @@ static void daemonize(void)
>   	close(0);
>   	close(1);
>   	close(2);
> +	fd = open("/dev/null", O_RDWR);
> +	if (fd >= 0) {
> +		/* dup2 to 0 / 1 / 2 (stdin / stdout / stderr) */
> +		dup2(fd, STDIN_FILENO);  /* 0 */
> +		dup2(fd, STDOUT_FILENO); /* 1 */
> +		dup2(fd, STDERR_FILENO); /* 2 */
> +
> +		/* Should be 0, but just in case it isn't... */
> +		if (fd > 2) {
> +			close(fd);
> +		}
> +	}
>   	openlog("ocfs2_controld", LOG_PID, LOG_DAEMON);
> 
>   	lockfile();
> 
> 
> _______________________________________________
> Ocfs2-devel mailing list
> Ocfs2-devel at oss.oracle.com
> http://oss.oracle.com/mailman/listinfo/ocfs2-devel

-- 

"Only a life lived for others is a life worth while."
							-Albert Einstein  

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127