From 1744a22ae948799da7927b53ec97ccc877ff9d61 Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 14 Dec 2021 09:22:12 +0000 Subject: 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: 6e0e99d58a65 ("afs: Fix mmap coherency vs 3rd-party changes") Reported-by: kafs-testing+fedora34_64checkkafs-build-300@auristor.com Suggested-by: Marc Dionne Signed-off-by: David Howells Tested-by: 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: Linus Torvalds --- fs/afs/file.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'fs/afs/file.c') diff --git a/fs/afs/file.c b/fs/afs/file.c index cb6ad61eec3b..afe4b803f84b 100644 --- a/fs/afs/file.c +++ b/fs/afs/file.c @@ -514,8 +514,9 @@ 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); - list_add_tail(&vnode->cb_mmap_link, - &vnode->volume->cell->fs_open_mmaps); + if (list_empty(&vnode->cb_mmap_link)) + list_add_tail(&vnode->cb_mmap_link, + &vnode->volume->cell->fs_open_mmaps); up_write(&vnode->volume->cell->fs_open_mmaps_lock); } -- cgit