Commit 1744a22a authored by David Howells's avatar David Howells Committed by Linus Torvalds
Browse files

afs: Fix mmap 



Fix afs_add_open_map() to check that the vnode isn't already on the list
when it adds it.  It's possible that afs_drop_open_mmap() decremented
the cb_nr_mmap counter, but hadn't yet got into the locked section to
remove it.

Also vnode->cb_mmap_link should be initialised, so fix that too.

Fixes: 6e0e99d5 ("afs: Fix mmap coherency vs 3rd-party changes")
Reported-by: default avatar <kafs-testing+fedora34_64checkkafs-build-300@auristor.com>
Suggested-by: default avatarMarc Dionne <marc.dionne@auristor.com>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Tested-by: default avatar <kafs-testing+fedora34_64checkkafs-build-300@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/686465.1639435380@warthog.procyon.org.uk/

 # v1
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 2b14864a

fs/afs/file.c

+3 −2
Original line number Diff line number Diff line
@@ -514,6 +514,7 @@ static void afs_add_open_mmap(struct afs_vnode *vnode) 
	if (atomic_inc_return(&vnode->cb_nr_mmap) == 1) {

		down_write(&vnode->volume->cell->fs_open_mmaps_lock);



		if (list_empty(&vnode->cb_mmap_link))

			list_add_tail(&vnode->cb_mmap_link,

				      &vnode->volume->cell->fs_open_mmaps);

fs/afs/super.c

+1 −0
Original line number Diff line number Diff line
@@ -667,6 +667,7 @@ static void afs_i_init_once(void *_vnode) 
	INIT_LIST_HEAD(&vnode->pending_locks);

	INIT_LIST_HEAD(&vnode->granted_locks);

	INIT_DELAYED_WORK(&vnode->lock_work, afs_lock_work);

	INIT_LIST_HEAD(&vnode->cb_mmap_link);

	seqlock_init(&vnode->cb_lock);

}