diff -up Linux-PAM-1.3.1/modules/pam_limits/limits.conf.5.xml.pam-limits-unlimited-value Linux-PAM-1.3.1/modules/pam_limits/limits.conf.5.xml
--- Linux-PAM-1.3.1/modules/pam_limits/limits.conf.5.xml.pam-limits-unlimited-value 2022-01-28 09:45:41.431606850 +0100
+++ Linux-PAM-1.3.1/modules/pam_limits/limits.conf.5.xml 2022-01-28 09:47:31.732430391 +0100
@@ -275,6 +275,8 @@
All items support the values <emphasis>-1</emphasis>,
<emphasis>unlimited</emphasis> or <emphasis>infinity</emphasis> indicating no limit,
except for <emphasis remap='B'>priority</emphasis> and <emphasis remap='B'>nice</emphasis>.
+ If <emphasis remap='B'>nofile</emphasis> is to be set to one of these values,
+ it will be set to the contents of /proc/sys/fs/nr_open instead (see setrlimit(3)).
</para>
<para>
If a hard limit or soft limit of a resource is set to a valid value,
diff -up Linux-PAM-1.3.1/modules/pam_limits/pam_limits.c.pam-limits-unlimited-value Linux-PAM-1.3.1/modules/pam_limits/pam_limits.c
--- Linux-PAM-1.3.1/modules/pam_limits/pam_limits.c.pam-limits-unlimited-value 2022-01-28 09:45:41.415606731 +0100
+++ Linux-PAM-1.3.1/modules/pam_limits/pam_limits.c 2022-01-28 09:45:41.431606850 +0100
@@ -487,6 +487,41 @@ static int init_limits(pam_handle_t *pam
return retval;
}
+/*
+ * Read the contents of <pathname> and return it in *valuep
+ * return 1 if conversion succeeds, result is in *valuep
+ * return 0 if conversion fails, *valuep is untouched.
+ */
+static int
+value_from_file(const char *pathname, rlim_t *valuep)
+{
+ char buf[128];
+ FILE *fp;
+ int retval;
+
+ retval = 0;
+
+ if ((fp = fopen(pathname, "r")) != NULL) {
+ if (fgets(buf, sizeof(buf), fp) != NULL) {
+ char *endptr;
+ unsigned long long value;
+
+ errno = 0;
+ value = strtoull(buf, &endptr, 10);
+ if (endptr != buf &&
+ (value != ULLONG_MAX || errno == 0) &&
+ (unsigned long long) (rlim_t) value == value) {
+ *valuep = (rlim_t) value;
+ retval = 1;
+ }
+ }
+
+ fclose(fp);
+ }
+
+ return retval;
+}
+
static void
process_limit (const pam_handle_t *pamh, int source, const char *lim_type,
const char *lim_item, const char *lim_value,
@@ -652,6 +687,20 @@ process_limit (const pam_handle_t *pamh,
rlimit_value = 20 - int_value;
break;
#endif
+ case RLIMIT_NOFILE:
+ /*
+ * If nofile is to be set to "unlimited", try to set it to
+ * the value in /proc/sys/fs/nr_open instead.
+ */
+ if (rlimit_value == RLIM_INFINITY) {
+ if (!value_from_file("/proc/sys/fs/nr_open", &rlimit_value))
+ pam_syslog(pamh, LOG_WARNING,
+ "Cannot set \"nofile\" to a sensible value");
+ else if (ctrl & PAM_DEBUG_ARG)
+ pam_syslog(pamh, LOG_DEBUG, "Setting \"nofile\" limit to %llu",
+ (unsigned long long) rlimit_value);
+ }
+ break;
}
if ( (limit_item != LIMIT_LOGIN)