[PATCH] use-before-uninitialized value in ext3(2)_find_ goal

[PATCH] use-before-uninitialized value in ext3(2)_find_ goal

From: Mingming Cao <cmm@us.ibm.com>

There is a uninitialized goal value being referenced in both ext3 and ext2
find goal block functions (ext3_find_goal() and ext2_find_goal()).

In the non-sequential write case, these functions check the goal value(non
zero) before calling ext3(2)_find_near() to find the goal block to
allocate.

Since the goal value is uninitialized(non zero), the ext3(2)_find_near() is
never being called in the non-sequential write, thus ext3(2)_find_goal()
failed to guide a goal block in the random write case.

ext3(2)_new_block() takes the junk goal value and will turn it to goal 0
since it's normally beyond the filesystem block number limit.  The fix is
trivial.