60720df8bf
commit 6ff38bd40230af35e446239396e5fc8ebd6a5248 upstream.
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.
[akpm@linux-foundation.org: add comment, per Jan]
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>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.