From: Willy Tarreau <w@1wt.eu>
Date: Thu, 22 Sep 2022 14:12:08 +0000 (+0200)
Subject: MINOR: init: do not try to shrink existing RLIMIT_NOFIlE
X-Git-Tag: v2.7-dev8~67
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c06557c23b0e4e932405fe3f0739c303ac90926e;p=thirdparty%2Fhaproxy.git

MINOR: init: do not try to shrink existing RLIMIT_NOFIlE

As seen in issue #1866, some environments will not allow to change the
current FD limit, and actually we don't need to do it, we only do it as
a byproduct of adjusting the limit to the one that fits. Here we're
replacing calls to setrlimit() with calls to raise_rlim_nofile(), which
will avoid making the setrlimit() syscall in case the desired value is
lower than the current process' one.

This depends on previous commit "MINOR: fd: add a new function to only
raise RLIMIT_NOFILE" and may need to be backported to 2.6, possibly
earlier, depending on users' experience in such environments.
---

diff --git a/src/extcheck.c b/src/extcheck.c
index 6b5b2b6852..2093b40514 100644
--- a/src/extcheck.c
+++ b/src/extcheck.c
@@ -419,7 +419,7 @@ static int connect_proc_chk(struct task *t)
 		/* restore the initial FD limits */
 		limit.rlim_cur = rlim_fd_cur_at_boot;
 		limit.rlim_max = rlim_fd_max_at_boot;
-		if (setrlimit(RLIMIT_NOFILE, &limit) == -1) {
+		if (raise_rlim_nofile(NULL, &limit) != 0) {
 			getrlimit(RLIMIT_NOFILE, &limit);
 			ha_warning("External check: failed to restore initial FD limits (cur=%u max=%u), using cur=%u max=%u\n",
 				   rlim_fd_cur_at_boot, rlim_fd_max_at_boot,
diff --git a/src/haproxy.c b/src/haproxy.c
index 6aff7d63ee..a95fc21e45 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -709,8 +709,7 @@ static void mworker_reexec()
 	/* restore the initial FD limits */
 	limit.rlim_cur = rlim_fd_cur_at_boot;
 	limit.rlim_max = rlim_fd_max_at_boot;
-	if (setrlimit(RLIMIT_NOFILE, &limit) == -1) {
-		getrlimit(RLIMIT_NOFILE, &limit);
+	if (raise_rlim_nofile(&limit, &limit) != 0) {
 		ha_warning("Failed to restore initial FD limits (cur=%u max=%u), using cur=%u max=%u\n",
 			   rlim_fd_cur_at_boot, rlim_fd_max_at_boot,
 			   (unsigned int)limit.rlim_cur, (unsigned int)limit.rlim_max);
@@ -1452,14 +1451,14 @@ static int check_if_maxsock_permitted(int maxsock)
 		return 1;
 
 	/* don't go further if we can't even set to what we have */
-	if (setrlimit(RLIMIT_NOFILE, &orig_limit) != 0)
+	if (raise_rlim_nofile(NULL, &orig_limit) != 0)
 		return 1;
 
 	test_limit.rlim_max = MAX(maxsock, orig_limit.rlim_max);
 	test_limit.rlim_cur = test_limit.rlim_max;
-	ret = setrlimit(RLIMIT_NOFILE, &test_limit);
+	ret = raise_rlim_nofile(NULL, &test_limit);
 
-	if (setrlimit(RLIMIT_NOFILE, &orig_limit) != 0)
+	if (raise_rlim_nofile(NULL, &orig_limit) != 0)
 		return 1;
 
 	return ret == 0;
@@ -3180,7 +3179,7 @@ int main(int argc, char **argv)
 		limit.rlim_max = MAX(rlim_fd_max_at_boot, limit.rlim_cur);
 
 		if ((global.fd_hard_limit && limit.rlim_cur > global.fd_hard_limit) ||
-		    setrlimit(RLIMIT_NOFILE, &limit) == -1) {
+		    raise_rlim_nofile(NULL, &limit) != 0) {
 			getrlimit(RLIMIT_NOFILE, &limit);
 			if (global.fd_hard_limit && limit.rlim_cur > global.fd_hard_limit)
 				limit.rlim_cur = global.fd_hard_limit;
@@ -3196,7 +3195,7 @@ int main(int argc, char **argv)
 				if (global.fd_hard_limit && limit.rlim_cur > global.fd_hard_limit)
 					limit.rlim_cur = global.fd_hard_limit;
 
-				if (setrlimit(RLIMIT_NOFILE, &limit) != -1)
+				if (raise_rlim_nofile(&limit, &limit) == 0)
 					getrlimit(RLIMIT_NOFILE, &limit);
 
 				ha_warning("[%s.main()] Cannot raise FD limit to %d, limit is %d.\n",