z3fold: fix retry mechanism in page reclaim

z3fold_page_reclaim()'s retry mechanism is broken: on a second iteration
it will have zhdr from the first one so that zhdr is no longer in line
with struct page.  That leads to crashes when the system is stressed.

Fix that by moving zhdr assignment up.

While at it, protect against using already freed handles by using own
local slots structure in z3fold_page_reclaim().

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Vitaly Wool <[email protected]>
Reported-by: Markus Linnala <[email protected]>
Reported-by: Chris Murphy <[email protected]>
Reported-by: Agustin Dall'Alba <[email protected]>
Cc: "Maciej S. Szmigiero" <[email protected]>
Cc: Shakeel Butt <[email protected]>
Cc: Henry Burns <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions