diff mbox series

[56/64] afs: Fix afs_write_end() to handle len > page size

Message ID	163819660464.215744.4576104569408497052.stgit@warthog.procyon.org.uk (mailing list archive)
State	New, archived
Headers	show Return-Path: <ceph-devel-owner@kernel.org> Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 56/64] afs: Fix afs_write_end() to handle len > page size From: David Howells <dhowells@redhat.com> To: linux-cachefs@redhat.com Cc: Jeff Layton <jlayton@kernel.org>, Jeff Layton <jlayton@kernel.org>, Marc Dionne <marc.dionne@auristor.com>, Al Viro <viro@zeniv.linux.org.uk>, Matthew Wilcox <willy@infradead.org>, linux-afs@lists.infradead.org, dhowells@redhat.com, Trond Myklebust <trondmy@hammerspace.com>, Anna Schumaker <anna.schumaker@netapp.com>, Steve French <sfrench@samba.org>, Dominique Martinet <asmadeus@codewreck.org>, Jeff Layton <jlayton@kernel.org>, Matthew Wilcox <willy@infradead.org>, Alexander Viro <viro@zeniv.linux.org.uk>, Omar Sandoval <osandov@osandov.com>, Linus Torvalds <torvalds@linux-foundation.org>, linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs-developer@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 29 Nov 2021 14:36:44 +0000 Message-ID: <163819660464.215744.4576104569408497052.stgit@warthog.procyon.org.uk> In-Reply-To: <163819575444.215744.318477214576928110.stgit@warthog.procyon.org.uk> References: <163819575444.215744.318477214576928110.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk
Series	fscache, cachefiles: Rewrite \| expand [00/64] fscache, cachefiles: Rewrite [01/64] fscache, cachefiles: Disable configuration [04/64] netfs: Display the netfs inode number in the netfs_read tracepoint [05/64] netfs: Pass a flag to ->prepare_write() to say if there's no alloc'd space [06/64] fscache: Introduce new driver [07/64] fscache: Implement a hash function [08/64] fscache: Implement cache registration [09/64] fscache: Implement volume registration [10/64] fscache: Implement cookie registration [11/64] fscache: Implement cache-level access helpers [12/64] fscache: Implement volume-level access helpers [13/64] fscache: Implement cookie-level access helpers [14/64] fscache: Implement functions add/remove a cache [15/64] fscache: Provide and use cache methods to lookup/create/free a volume [16/64] fscache: Add a function for a cache backend to note an I/O error [17/64] fscache: Implement simple cookie state machine [18/64] fscache: Implement cookie user counting and resource pinning [19/64] fscache: Implement cookie invalidation [20/64] fscache: Provide a means to begin an operation [21/64] fscache: Count data storage objects in a cache [22/64] fscache: Provide read/write stat counters for the cache [23/64] fscache: Provide a function to let the netfs update its coherency data [24/64] netfs: Pass more information on how to deal with a hole in the cache [25/64] fscache: Implement raw I/O interface [26/64] fscache: Implement higher-level write I/O interface [27/64] vfs, fscache: Implement pinning of cache usage for writeback [28/64] fscache: Provide a function to note the release of a page [29/64] fscache: Provide a function to resize a cookie [30/64] cachefiles: Introduce rewritten driver [31/64] cachefiles: Define structs [32/64] cachefiles: Add some error injection support [33/64] cachefiles: Add a couple of tracepoints for logging errors [34/64] cachefiles: Add cache error reporting macro [35/64] cachefiles: Add security derivation [36/64] cachefiles: Register a miscdev and parse commands over it [37/64] cachefiles: Provide a function to check how much space there is [38/64] vfs, cachefiles: Mark a backing file in use with an inode flag [39/64] cachefiles: Implement a function to get/create a directory in the cache [40/64] cachefiles: Implement cache registration and withdrawal [41/64] cachefiles: Implement volume support [42/64] cachefiles: Add tracepoints for calls to the VFS [43/64] cachefiles: Implement object lifecycle funcs [44/64] cachefiles: Implement key to filename encoding [45/64] cachefiles: Implement metadata/coherency data storage in xattrs [46/64] cachefiles: Mark a backing file in use with an inode flag [47/64] cachefiles: Implement culling daemon commands [48/64] cachefiles: Implement backing file wrangling [49/64] cachefiles: Implement begin and end I/O operation [50/64] cachefiles: Implement cookie resize for truncate [51/64] cachefiles: Implement the I/O routines [52/64] cachefiles: Allow cachefiles to actually function [53/64] fscache, cachefiles: Display stats of no-space events [54/64] fscache, cachefiles: Display stat of culling events [55/64] afs: Handle len being extending over page end in write_begin/write_end [56/64] afs: Fix afs_write_end() to handle len > page size [57/64] afs: Convert afs to use the new fscache API [58/64] afs: Copy local writes to the cache when writing to the server [59/64] afs: Skip truncation on the server of data we haven't written yet [60/64] 9p: Use fscache indexing rewrite and reenable caching [61/64] 9p: Copy local writes to the cache when writing to the server [62/64] nfs: Convert to new fscache volume/cookie API [63/64] cifs: Support fscache indexing rewrite (untested)

Commit Message

David Howells Nov. 29, 2021, 2:36 p.m. UTC

It is possible for the len argument to afs_write_end() to overrun the end
of the page (len is used to key the size of the page in afs_write_start()
when compound pages become a regular thing).

Fix afs_write_end() to correctly trim the write length so that it doesn't
exceed the end of the page.

Fixes: 3003bbd0697b ("afs: Use the netfs_write_begin() helper")
Reported-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: Matthew Wilcox <willy@infradead.org>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/162367682522.460125.5652091227576721609.stgit@warthog.procyon.org.uk/ # v1
---

 fs/afs/write.c |    1 +
 1 file changed, 1 insertion(+)

diff mbox series

Patch

diff --git a/fs/afs/write.c b/fs/afs/write.c
index 8e4e87d66855..9db3ddb1c45b 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -120,6 +120,7 @@  int afs_write_end(struct file *file, struct address_space *mapping,
 	_enter("{%llx:%llu},{%lx}",
 	       vnode->fid.vid, vnode->fid.vnode, folio_index(folio));
 
+	len = min_t(size_t, len, folio_size(folio) - from);
 	if (!folio_test_uptodate(folio)) {
 		if (copied < len) {
 			copied = 0;