[PATCH-2.4] EXT3: avoid crashing due to divide by zero

[Willy Tarreau]

Hi Stephen,

I've been having this very old patch in my queue that has been merged
in 2.6 but not in 2.4. As I've been hit at least once by this problem,
I'm about to merge it into 2.4 too, as well as its ext2 equivalent
(equally in 2.6). Do you have any objection ?

Thanks in advance,
Willy