Module Name: src
Committed By: christos
Date: Sun May 5 20:45:08 UTC 2019
Modified Files:
src/sys/kern: sys_select.c
Log Message:
Remove the slop code. Suggested by mrg@
To generate a diff of this commit:
cvs rdiff -u -r1.42 -r1.43 src/sys/kern/sys_select.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/sys_select.c
diff -u src/sys/kern/sys_select.c:1.42 src/sys/kern/sys_select.c:1.43
--- src/sys/kern/sys_select.c:1.42 Sat May 4 11:46:58 2019
+++ src/sys/kern/sys_select.c Sun May 5 16:45:08 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_select.c,v 1.42 2019/05/04 15:46:58 christos Exp $ */
+/* $NetBSD: sys_select.c,v 1.43 2019/05/05 20:45:08 christos Exp $ */
/*-
* Copyright (c) 2007, 2008, 2009, 2010 The NetBSD Foundation, Inc.
@@ -84,7 +84,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_select.c,v 1.42 2019/05/04 15:46:58 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_select.c,v 1.43 2019/05/05 20:45:08 christos Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -488,14 +488,18 @@ pollcommon(register_t *retval, struct po
int error;
size_t ni;
- if (nfds > MAX(1000 + curlwp->l_fd->fd_dt->dt_nfiles,
- curlwp->l_proc->p_rlimit[RLIMIT_NOFILE].rlim_cur)) {
+ if (nfds > curlwp->l_proc->p_rlimit[RLIMIT_NOFILE].rlim_cur) {
/*
- * Either the user passed in a very sparse 'fds' or junk!
- * The kmem_alloc() call below would be bad news.
- * We could process the 'fds' array in chunks, but that
+ * Prevent userland from causing over-allocation.
+ * Raising the default limit too high can still cause
+ * a lot of memory to be allocated, but this also means
+ * that the file descriptor array will also be large.
+ *
+ * To reduce the memory requirements here, we could
+ * process the 'fds' array in chunks, but that
* is a lot of code that isn't normally useful.
* (Or just move the copyin/out into pollscan().)
+ *
* Historically the code silently truncated 'fds' to
* dt_nfiles entries - but that does cause issues.
*/
