BUG/MEDIUM: listeners: CLOEXEC flag is not correctly set
The CLOEXEC flag was set using a F_SETFL which can't work.
To set the CLOEXEC flag F_SETFD should be used, the problem is that it
needs a new call to fcntl() and it's on the path of every accept.
This flag was only needed in the case of the master, so the patch was
reverted and the flag set only in this case.
The bug was introduced by 0b3e849 ("MEDIUM: listeners: set O_CLOEXEC on
the accepted FDs").
No backport needed.
diff --git a/src/listener.c b/src/listener.c
index c75f8ef..37466d4 100644
--- a/src/listener.c
+++ b/src/listener.c
@@ -544,7 +544,7 @@
/* with sockpair@ we don't want to do an accept */
if (unlikely(l->addr.ss_family == AF_CUST_SOCKPAIR)) {
if ((cfd = recv_fd_uxst(fd)) != -1)
- fcntl(cfd, F_SETFL, O_NONBLOCK|O_CLOEXEC);
+ fcntl(cfd, F_SETFL, O_NONBLOCK);
} else
#ifdef USE_ACCEPT4
@@ -552,12 +552,12 @@
* fallback to the legacy accept() + fcntl().
*/
if (unlikely(accept4_broken ||
- ((cfd = accept4(fd, (struct sockaddr *)&addr, &laddr, SOCK_NONBLOCK|SOCK_CLOEXEC)) == -1 &&
+ ((cfd = accept4(fd, (struct sockaddr *)&addr, &laddr, SOCK_NONBLOCK)) == -1 &&
(errno == ENOSYS || errno == EINVAL || errno == EBADF) &&
(accept4_broken = 1))))
#endif
if ((cfd = accept(fd, (struct sockaddr *)&addr, &laddr)) != -1)
- fcntl(cfd, F_SETFL, O_NONBLOCK|O_CLOEXEC);
+ fcntl(cfd, F_SETFL, O_NONBLOCK);
if (unlikely(cfd == -1)) {
switch (errno) {
@@ -604,6 +604,10 @@
}
}
+ /* we don't want to leak the FD upon reload if it's in the master */
+ if (unlikely(master == 1))
+ fcntl(cfd, F_SETFD, FD_CLOEXEC);
+
if (unlikely(cfd >= global.maxsock)) {
send_log(p, LOG_EMERG,
"Proxy %s reached the configured maximum connection limit. Please check the global 'maxconn' value.\n",