Re: kern/50511 (npf fails to load tree file above certain size)

[Geoff Wing <gcw%pobox.com@localhost>]

The following reply was made to PR kern/50511; it has been noted by GNATS.

From: Geoff Wing <gcw%pobox.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/50511 (npf fails to load tree file above certain size)
Date: Wed, 17 Aug 2016 18:04:11 +1000

 This is hitting an arbitrary limit in proplib (65536 byte limit on an
 ioctl) in _prop_object_copyin()
 
 from common/lib/libprop/prop_kern.c:
 	/* Arbitrary limit ioctl input to 64KB */
 	unsigned int prop_object_copyin_limit = 65536;
 
 On my amd64 system each table line is taking around 121 bytes.  Tables
 with, say, 4400 lines want over 1/2 MB.
 
 Patch below shows the total size it tries to copy.
 
 Index: common/lib/libprop/prop_kern.c
 ===================================================================
 RCS file: /cvsroot/src/common/lib/libprop/prop_kern.c,v
 retrieving revision 1.19
 diff -u -r1.19 prop_kern.c
 --- common/lib/libprop/prop_kern.c	11 May 2015 16:48:34 -0000	1.19
 +++ common/lib/libprop/prop_kern.c	17 Aug 2016 07:55:06 -0000
 @@ -407,8 +407,10 @@
  	char *buf;
  	int error;
  
 -	if (pref->pref_len >= prop_object_copyin_limit)
 +	if (pref->pref_len >= prop_object_copyin_limit) {
 +		printf("_prop_object_copyin: requested object size (%u) above limit\n", (unsigned int) pref->pref_len);
  		return EINVAL;
 +	}
  
  	/*
  	 * Allocate an extra byte so we can guarantee NUL-termination.