diff options
| -rw-r--r-- | fs/namei.c | 62 |
1 files changed, 33 insertions, 29 deletions
diff --git a/fs/namei.c b/fs/namei.c index 1c9af92518a1..1b4bc1b7ffae 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1566,15 +1566,31 @@ static void terminate_walk(struct nameidata *nd) put_link(nd); } +static int pick_link(struct nameidata *nd, struct path *link) +{ + if (nd->flags & LOOKUP_RCU) { + if (unlikely(nd->path.mnt != link->mnt || + unlazy_walk(nd, link->dentry))) { + return -ECHILD; + } + } + nd->link = *link; + return 1; +} + /* * Do we need to follow links? We _really_ want to be able * to do this check without having to look at inode->i_op, * so we keep a cache of "no, this doesn't need follow_link" * for the common case. */ -static inline int should_follow_link(struct dentry *dentry, int follow) +static inline int should_follow_link(struct nameidata *nd, struct path *link, int follow) { - return unlikely(d_is_symlink(dentry)) ? follow : 0; + if (likely(!d_is_symlink(link->dentry))) + return 0; + if (!follow) + return 0; + return pick_link(nd, link); } enum {WALK_GET = 1, WALK_PUT = 2}; @@ -1612,17 +1628,9 @@ static int walk_component(struct nameidata *nd, int flags) if (flags & WALK_PUT) put_link(nd); - if (should_follow_link(path.dentry, flags & WALK_GET)) { - if (nd->flags & LOOKUP_RCU) { - if (unlikely(nd->path.mnt != path.mnt || - unlazy_walk(nd, path.dentry))) { - return -ECHILD; - } - } - BUG_ON(inode != path.dentry->d_inode); - nd->link = path; - return 1; - } + err = should_follow_link(nd, &path, flags & WALK_GET); + if (unlikely(err)) + return err; path_to_nameidata(&path, nd); nd->inode = inode; return 0; @@ -2375,9 +2383,11 @@ done: put_link(nd); path->dentry = dentry; path->mnt = nd->path.mnt; - if (should_follow_link(dentry, nd->flags & LOOKUP_FOLLOW)) { - nd->link = *path; - return 1; + error = should_follow_link(nd, path, nd->flags & LOOKUP_FOLLOW); + if (unlikely(error)) { + if (error < 0) + goto out; + return error; } mntget(path->mnt); follow_mount(path); @@ -3095,19 +3105,13 @@ retry_lookup: goto out; } finish_lookup: - if (should_follow_link(path.dentry, nd->flags & LOOKUP_FOLLOW)) { - if (nd->flags & LOOKUP_RCU) { - if (unlikely(nd->path.mnt != path.mnt || - unlazy_walk(nd, path.dentry))) { - error = -ECHILD; - goto out; - } - } - BUG_ON(inode != path.dentry->d_inode); - if (nd->depth) - put_link(nd); - nd->link = path; - return 1; + if (nd->depth) + put_link(nd); + error = should_follow_link(nd, &path, nd->flags & LOOKUP_FOLLOW); + if (unlikely(error)) { + if (error < 0) + goto out; + return error; } if (unlikely(d_is_symlink(path.dentry)) && !(open_flag & O_PATH)) { |