tree 730892c9d4d9dbab03c77597e822a7cb79c9cd96
parent f05b6284ee5d3be51ebe22284fc4b25fc586f380
author Hugh Dickins <hugh@veritas.com> 1171100580 -0800
committer Linus Torvalds <torvalds@woody.linux-foundation.org> 1171219877 -0800

[PATCH] page_mkwrite caller race fix

After do_wp_page has tested page_mkwrite, it must release old_page after
acquiring page table lock, not before: at some stage that ordering got
reversed, leaving a (very unlikely) window in which old_page might be
truncated, freed, and reused in the same position.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>