Re: kernel/6426: Kernel panic in ffs_dirpref() at mkdir on a freshly created very large ffs2 fs

[Otto Moerbeek]

The following reply was made to PR kernel/6426; it has been noted by GNATS.

From: Otto Moerbeek <o...@drijf.net>
To: Benny Lofgren <bl-li...@lofgren.biz>
Cc: gn...@openbsd.org, r...@skynet.internetlabbet.net
Subject: Re: kernel/6426: Kernel panic in ffs_dirpref() at mkdir on a freshly 
created very large ffs2 fs
Date: Sat, 10 Jul 2010 18:23:54 +0200

 Hi,
 
 Very good chanche this fixes your problem. From FreeBSD.
 
        -Otto
        
 Index: ffs_alloc.c
 ===================================================================
 RCS file: /cvs/src/sys/ufs/ffs/ffs_alloc.c,v
 retrieving revision 1.88
 diff -u -p -r1.88 ffs_alloc.c
 --- ffs_alloc.c        16 Jan 2010 15:45:10 -0000      1.88
 +++ ffs_alloc.c        10 Jul 2010 16:22:16 -0000
 @@ -983,7 +983,10 @@ ffs_dirpref(struct inode *pip)
        curdirsize = avgndir ? (cgsize - avgbfree * fs->fs_bsize) / avgndir : 0;
        if (dirsize < curdirsize)
                dirsize = curdirsize;
 -      maxcontigdirs = min(avgbfree * fs->fs_bsize  / dirsize, 255);
 +      if (dirsize <= 0)
 +              maxcontigdirs = 0;              /* dirsize overflowed */
 +      else
 +              maxcontigdirs = min(avgbfree * fs->fs_bsize  / dirsize, 255);
        if (fs->fs_avgfpdir > 0)
                maxcontigdirs = min(maxcontigdirs,
                                    fs->fs_ipg / fs->fs_avgfpdir);