All places where we call set_mnt_shared() are guaranteed to have
non-zero ->mnt_group_id - either by explicit test, or by having
done successful invent_group_ids() covering the same mount since
we'd grabbed namespace_sem.
The opposite combination (non-zero ->mnt_group_id and !IS_MNT_SHARED())
*is* possible - it means that we have allocated group id, but didn't
get around to set_mnt_shared() yet; such state is transient -
by the time we do namespace_unlock(), we must either do set_mnt_shared()
or unroll the group id allocations by cleanup_group_ids().
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/namespace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/namespace.c b/fs/namespace.c
index ca36c4a6a143..a75438121417 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2516,7 +2516,7 @@ static int invent_group_ids(struct mount *mnt, bool recurse)
struct mount *p;
for (p = mnt; p; p = recurse ? next_mnt(p, mnt) : NULL) {
- if (!p->mnt_group_id && !IS_MNT_SHARED(p)) {
+ if (!p->mnt_group_id) {
int err = mnt_alloc_group_id(p);
if (err) {
cleanup_group_ids(mnt, p);
--
2.39.5
