bin/185393: find -lname buffer read overflow bug

[Ben Reser]

The following reply was made to PR bin/185393; it has been noted by GNATS.

From: Ben Reser <ben at reser.org>
To: bug-followup at FreeBSD.org
Cc:  
Subject: Re: bin/185393: find -lname buffer read overflow bug
Date: Wed, 01 Jan 2014 12:03:04 -0800

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 Correction on the patch.  Forgot to subtract one byte from the buffer to allow
 for the NULL character to be set.  Updated patch attached.
 
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 Index: usr.bin/find/function.c
 ===================================================================
 --- usr.bin/find/function.c	(revision 260159)
 +++ usr.bin/find/function.c	(working copy)
 @@ -1124,9 +1124,11 @@ f_name(PLAN *plan, FTSENT *entry)
  	const char *name;
  
  	if (plan->flags & F_LINK) {
 +		int len = readlink(entry->fts_path, fn, sizeof(fn) - 1);
 +		if (len == -1)
 +			return 0;
 +		fn[len] = '\0';
  		name = fn;
 -		if (readlink(entry->fts_path, fn, sizeof(fn)) == -1)
 -			return 0;
  	} else
  		name = entry->fts_name;
  	return !fnmatch(plan->c_data, name,
 
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