svn commit: r361109 - stable/11/sys/kern

[Konstantin Belousov]

Author: kib
Date: Sat May 16 09:40:17 2020
New Revision: 361109
URL: https://svnweb.freebsd.org/changeset/base/361109

Log:
  MFC r360845:
  Avoid spurious ENOMEMs from sysctl hw.pagesizes.
  
  PR:	246215

Modified:
  stable/11/sys/kern/kern_mib.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/kern/kern_mib.c
==============================================================================
--- stable/11/sys/kern/kern_mib.c	Sat May 16 09:03:18 2020	(r361108)
+++ stable/11/sys/kern/kern_mib.c	Sat May 16 09:40:17 2020	(r361109)
@@ -228,6 +228,7 @@ static int
 sysctl_hw_pagesizes(SYSCTL_HANDLER_ARGS)
 {
 	int error;
+	size_t len;
 #ifdef SCTL_MASK32
 	int i;
 	uint32_t pagesizes32[MAXPAGESIZES];
@@ -240,10 +241,18 @@ sysctl_hw_pagesizes(SYSCTL_HANDLER_ARGS)
 		for (i = 0; i < MAXPAGESIZES; i++)
 			pagesizes32[i] = (uint32_t)pagesizes[i];
 
-		error = SYSCTL_OUT(req, pagesizes32, sizeof(pagesizes32));
+		len = sizeof(pagesizes32);
+		if (len > req->oldlen)
+			len = req->oldlen;
+		error = SYSCTL_OUT(req, pagesizes32, len);
 	} else
 #endif
-		error = SYSCTL_OUT(req, pagesizes, sizeof(pagesizes));
+	{
+		len = sizeof(pagesizes);
+		if (len > req->oldlen)
+			len = req->oldlen;
+		error = SYSCTL_OUT(req, pagesizes, len);
+	}
 	return (error);
 }
 SYSCTL_PROC(_hw, OID_AUTO, pagesizes, CTLTYPE_ULONG | CTLFLAG_RD,