diff options
Diffstat (limited to 'fs/overlayfs/super.c')
| -rw-r--r-- | fs/overlayfs/super.c | 45 |
1 files changed, 39 insertions, 6 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index fe511192f83c..b63474d1b064 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -91,7 +91,24 @@ static int ovl_revalidate_real(struct dentry *d, unsigned int flags, bool weak) if (d->d_flags & DCACHE_OP_WEAK_REVALIDATE) ret = d->d_op->d_weak_revalidate(d, flags); } else if (d->d_flags & DCACHE_OP_REVALIDATE) { - ret = d->d_op->d_revalidate(d, flags); + struct dentry *parent; + struct inode *dir; + struct name_snapshot n; + + if (flags & LOOKUP_RCU) { + parent = READ_ONCE(d->d_parent); + dir = d_inode_rcu(parent); + if (!dir) + return -ECHILD; + } else { + parent = dget_parent(d); + dir = d_inode(parent); + } + take_dentry_name_snapshot(&n, d); + ret = d->d_op->d_revalidate(dir, &n.name, d, flags); + release_dentry_name_snapshot(&n); + if (!(flags & LOOKUP_RCU)) + dput(parent); if (!ret) { if (!(flags & LOOKUP_RCU)) d_invalidate(d); @@ -127,7 +144,8 @@ static int ovl_dentry_revalidate_common(struct dentry *dentry, return ret; } -static int ovl_dentry_revalidate(struct dentry *dentry, unsigned int flags) +static int ovl_dentry_revalidate(struct inode *dir, const struct qstr *name, + struct dentry *dentry, unsigned int flags) { return ovl_dentry_revalidate_common(dentry, flags, false); } @@ -309,9 +327,10 @@ retry: goto retry; } - err = ovl_mkdir_real(ofs, dir, &work, attr.ia_mode); - if (err) - goto out_dput; + work = ovl_do_mkdir(ofs, dir, work, attr.ia_mode); + err = PTR_ERR(work); + if (IS_ERR(work)) + goto out_err; /* Weird filesystem returning with hashed negative (kernfs)? */ err = -EINVAL; @@ -1287,6 +1306,7 @@ int ovl_fill_super(struct super_block *sb, struct fs_context *fc) { struct ovl_fs *ofs = sb->s_fs_info; struct ovl_fs_context *ctx = fc->fs_private; + const struct cred *old_cred = NULL; struct dentry *root_dentry; struct ovl_entry *oe; struct ovl_layer *layers; @@ -1300,10 +1320,15 @@ int ovl_fill_super(struct super_block *sb, struct fs_context *fc) sb->s_d_op = &ovl_dentry_operations; err = -ENOMEM; - ofs->creator_cred = cred = prepare_creds(); + if (!ofs->creator_cred) + ofs->creator_cred = cred = prepare_creds(); + else + cred = (struct cred *)ofs->creator_cred; if (!cred) goto out_err; + old_cred = ovl_override_creds(sb); + err = ovl_fs_params_verify(ctx, &ofs->config); if (err) goto out_err; @@ -1463,11 +1488,19 @@ int ovl_fill_super(struct super_block *sb, struct fs_context *fc) sb->s_root = root_dentry; + ovl_revert_creds(old_cred); return 0; out_free_oe: ovl_free_entry(oe); out_err: + /* + * Revert creds before calling ovl_free_fs() which will call + * put_cred() and put_cred() requires that the cred's that are + * put are not the caller's creds, i.e., current->cred. + */ + if (old_cred) + ovl_revert_creds(old_cred); ovl_free_fs(ofs); sb->s_fs_info = NULL; return err; |