diff options
Diffstat (limited to 'fs/dcache.c')
| -rw-r--r-- | fs/dcache.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 9b5fe503f6cb..5c33aeb0f68f 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2718,7 +2718,7 @@ struct dentry *d_ancestor(struct dentry *p1, struct dentry *p2) * This helper attempts to cope with remotely renamed directories * * It assumes that the caller is already holding - * dentry->d_parent->d_inode->i_mutex, inode->i_lock and rename_lock + * dentry->d_parent->d_inode->i_mutex, and rename_lock * * Note: If ever the locking in lock_rename() changes, then please * remember to update this too... @@ -2744,7 +2744,6 @@ out_unalias: __d_move(alias, dentry, false); ret = 0; out_err: - spin_unlock(&inode->i_lock); if (m2) mutex_unlock(m2); if (m1) @@ -2790,10 +2789,11 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) if (S_ISDIR(inode->i_mode)) { struct dentry *new = __d_find_any_alias(inode); if (unlikely(new)) { + /* The reference to new ensures it remains an alias */ + spin_unlock(&inode->i_lock); write_seqlock(&rename_lock); if (unlikely(d_ancestor(new, dentry))) { write_sequnlock(&rename_lock); - spin_unlock(&inode->i_lock); dput(new); new = ERR_PTR(-ELOOP); pr_warn_ratelimited( @@ -2812,7 +2812,6 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) } else { __d_move(new, dentry, false); write_sequnlock(&rename_lock); - spin_unlock(&inode->i_lock); security_d_instantiate(new, inode); } iput(inode); @@ -2926,6 +2925,13 @@ restart: if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) { struct mount *parent = ACCESS_ONCE(mnt->mnt_parent); + /* Escaped? */ + if (dentry != vfsmnt->mnt_root) { + bptr = *buffer; + blen = *buflen; + error = 3; + break; + } /* Global root? */ if (mnt != parent) { dentry = ACCESS_ONCE(mnt->mnt_mountpoint); |