Combination of LOOKUP_IS_SCOPED and NULL nd->root.mnt is impossible
after successful path_init(). All places where ->root.mnt might
become NULL do that only if LOOKUP_IS_SCOPED is not there and
path_init() itself can return success without setting nd->root
only if ND_ROOT_PRESET had been set (in which case nd->root
had been set by caller and never changed) or if the name had
been a relative one *and* none of the bits in LOOKUP_IS_SCOPED
had been present.
Since all calls of legitimize_root() must be downstream of successful
path_init(), the check for !nd->root.mnt && (nd->flags & LOOKUP_IS_SCOPED)
is pure paranoia.
FWIW, it had been discussed (and agreed upon) with Aleksa back when
scoped lookups had been merged; looks like that had fallen through the
cracks back then.
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/namei.c | 7 -------
1 file changed, 7 deletions(-)
diff --git a/fs/namei.c b/fs/namei.c
index 2d6b94a950fe..bfe4ec9e282b 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -729,13 +729,6 @@ static bool legitimize_links(struct nameidata *nd)
static bool legitimize_root(struct nameidata *nd)
{
- /*
- * For scoped-lookups (where nd->root has been zeroed), we need to
- * restart the whole lookup from scratch -- because set_root() is wrong
- * for these lookups (nd->dfd is the root, not the filesystem root).
- */
- if (!nd->root.mnt && (nd->flags & LOOKUP_IS_SCOPED))
- return false;
/* Nothing to do if nd->root is zero or is managed by the VFS user. */
if (!nd->root.mnt || (nd->state & ND_ROOT_PRESET))
return true;
--
2.30.2
