ReiserFS buglet

[Jakob Oestergaard <jakob@unthought.net>]

First:

In linux-2.4.19, I found the following:

fs/reiserfs/super.c:707

 s->s_blocksize = sb_blocksize(rs);
 s->s_blocksize_bits = 0;
 while ((1 << s->s_blocksize_bits) != s->s_blocksize)
     s->s_blocksize_bits ++;


What happens if there's a bit-flip on the disk so that s->s_blocksize is
not a power of two ?

I would suggest replacing the '!=' with a '<' in the while loop and
adding a sanity check afterwards.

After all, a single bit-flip in the root fs superblock would cause the
system to hang silently (but spinning really fast!) at boot.


Second:

As I see it, the ReiserFS journal has the same problems as jbd wrt. to
atomicity of write operations of indexes.  Please see my recent mail
about the jbd problems.


-- 
................................................................
:   jakob@unthought.net   : And I see the elder races,         :
:.........................: putrid forms of man                :
:   Jakob Østergaard      : See him rise and claim the earth,  :
:        OZ9ABN           : his downfall is at hand.           :
:.........................:............{Konkhra}...............: