diff options
| -rw-r--r-- | fs/namei.c | 41 | ||||
| -rw-r--r-- | include/linux/namei.h | 1 |
2 files changed, 16 insertions, 26 deletions
diff --git a/fs/namei.c b/fs/namei.c index 2af485ddc507..671c3c1a3425 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -596,14 +596,12 @@ static void terminate_walk(struct nameidata *nd) path_put(&nd->path); for (i = 0; i < nd->depth; i++) path_put(&nd->stack[i].link); - if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) { + if (nd->flags & LOOKUP_ROOT_GRABBED) { path_put(&nd->root); - nd->root.mnt = NULL; + nd->flags &= ~LOOKUP_ROOT_GRABBED; } } else { nd->flags &= ~LOOKUP_RCU; - if (!(nd->flags & LOOKUP_ROOT)) - nd->root.mnt = NULL; rcu_read_unlock(); } nd->depth = 0; @@ -645,6 +643,7 @@ static bool legitimize_root(struct nameidata *nd) { if (!nd->root.mnt || (nd->flags & LOOKUP_ROOT)) return true; + nd->flags |= LOOKUP_ROOT_GRABBED; return legitimize_path(nd, &nd->root, nd->root_seq); } @@ -678,21 +677,18 @@ static int unlazy_walk(struct nameidata *nd) nd->flags &= ~LOOKUP_RCU; if (unlikely(!legitimize_links(nd))) - goto out2; - if (unlikely(!legitimize_path(nd, &nd->path, nd->seq))) goto out1; + if (unlikely(!legitimize_path(nd, &nd->path, nd->seq))) + goto out; if (unlikely(!legitimize_root(nd))) goto out; rcu_read_unlock(); BUG_ON(nd->inode != parent->d_inode); return 0; -out2: +out1: nd->path.mnt = NULL; nd->path.dentry = NULL; -out1: - if (!(nd->flags & LOOKUP_ROOT)) - nd->root.mnt = NULL; out: rcu_read_unlock(); return -ECHILD; @@ -732,21 +728,14 @@ static int unlazy_child(struct nameidata *nd, struct dentry *dentry, unsigned se */ if (unlikely(!lockref_get_not_dead(&dentry->d_lockref))) goto out; - if (unlikely(read_seqcount_retry(&dentry->d_seq, seq))) { - rcu_read_unlock(); - dput(dentry); - goto drop_root_mnt; - } + if (unlikely(read_seqcount_retry(&dentry->d_seq, seq))) + goto out_dput; /* * Sequence counts matched. Now make sure that the root is * still valid and get it if required. */ - if (unlikely(!legitimize_root(nd))) { - rcu_read_unlock(); - dput(dentry); - return -ECHILD; - } - + if (unlikely(!legitimize_root(nd))) + goto out_dput; rcu_read_unlock(); return 0; @@ -756,9 +745,10 @@ out1: nd->path.dentry = NULL; out: rcu_read_unlock(); -drop_root_mnt: - if (!(nd->flags & LOOKUP_ROOT)) - nd->root.mnt = NULL; + return -ECHILD; +out_dput: + rcu_read_unlock(); + dput(dentry); return -ECHILD; } @@ -822,6 +812,7 @@ static void set_root(struct nameidata *nd) } while (read_seqcount_retry(&fs->seq, seq)); } else { get_fs_root(fs, &nd->root); + nd->flags |= LOOKUP_ROOT_GRABBED; } } @@ -1738,8 +1729,6 @@ static int pick_link(struct nameidata *nd, struct path *link, nd->flags &= ~LOOKUP_RCU; nd->path.mnt = NULL; nd->path.dentry = NULL; - if (!(nd->flags & LOOKUP_ROOT)) - nd->root.mnt = NULL; rcu_read_unlock(); } else if (likely(unlazy_walk(nd)) == 0) error = nd_alloc_stack(nd); diff --git a/include/linux/namei.h b/include/linux/namei.h index b7993980516e..397a08ade6a2 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -37,6 +37,7 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND}; #define LOOKUP_NO_REVAL 0x0080 #define LOOKUP_JUMPED 0x1000 #define LOOKUP_ROOT 0x2000 +#define LOOKUP_ROOT_GRABBED 0x0008 extern int path_pts(struct path *path); |