The patch titled Subject: mm: cleancache: fix corruption on missed inode invalidation has been added to the -mm tree. Its filename is mm-cleancache-fix-corruption-on-missed-inode-invalidation.patch
This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-cleancache-fix-corruption-on-mis... and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-cleancache-fix-corruption-on-mis...
Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated there every 3-4 working days
------------------------------------------------------ From: Pavel Tikhomirov ptikhomirov@virtuozzo.com Subject: mm: cleancache: fix corruption on missed inode invalidation
If all pages are deleted from the mapping by memory reclaim and also moved to the cleancache:
__delete_from_page_cache (no shadow case) unaccount_page_cache_page cleancache_put_page page_cache_delete mapping->nrpages -= nr (nrpages becomes 0)
We don't clean the cleancache for an inode after final file truncation (removal).
truncate_inode_pages_final check (nrpages || nrexceptional) is false no truncate_inode_pages no cleancache_invalidate_inode(mapping)
These way when reading the new file created with same inode we may get these trash leftover pages from cleancache and see wrong data instead of the contents of the new file.
Fix it by always doing truncate_inode_pages which is already ready for nrpages == 0 && nrexceptional == 0 case and just invalidates inode.
Link: http://lkml.kernel.org/r/20181112095734.17979-1-ptikhomirov@virtuozzo.com Fixes: commit 91b0abe36a7b ("mm + fs: store shadow entries in page cache") Signed-off-by: Pavel Tikhomirov ptikhomirov@virtuozzo.com Reviewed-by: Vasily Averin vvs@virtuozzo.com Reviewed-by: Andrey Ryabinin aryabinin@virtuozzo.com Reviewed-by: Jan Kara jack@suse.cz Cc: Johannes Weiner hannes@cmpxchg.org Cc: Mel Gorman mgorman@techsingularity.net Cc: Matthew Wilcox willy@infradead.org Cc: Andi Kleen ak@linux.intel.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
mm/truncate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/mm/truncate.c~mm-cleancache-fix-corruption-on-missed-inode-invalidation +++ a/mm/truncate.c @@ -517,9 +517,9 @@ void truncate_inode_pages_final(struct a */ xa_lock_irq(&mapping->i_pages); xa_unlock_irq(&mapping->i_pages); - - truncate_inode_pages(mapping, 0); } + + truncate_inode_pages(mapping, 0); } EXPORT_SYMBOL(truncate_inode_pages_final);
_
Patches currently in -mm which might be from ptikhomirov@virtuozzo.com are
mm-cleancache-fix-corruption-on-missed-inode-invalidation.patch