Andrew Beekhof
2008-Nov-18 10:18 UTC
[Ocfs2-devel] [Patch 2/3] ocfs2-tools: ocfs2_controld leaves std(in|out|err) unassigned
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 at 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();
Joel Becker
2008-Nov-18 23:02 UTC
[Ocfs2-devel] [Patch 2/3] ocfs2-tools: ocfs2_controld leaves std(in|out|err) unassigned
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 at suse.de>Signed-off-by: Joel Becker <joel.becker at 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