diff options
Diffstat (limited to '')
| -rw-r--r-- | fs/overlayfs/inode.c | 49 |
1 files changed, 43 insertions, 6 deletions
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index f84492ff505d..5becbaf1cec7 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -41,6 +41,7 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr) { int err; struct dentry *upperdentry; + const struct cred *old_cred; /* * Check for permissions before trying to copy-up. This is redundant @@ -84,7 +85,9 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr) attr->ia_valid &= ~ATTR_MODE; inode_lock(upperdentry->d_inode); + old_cred = ovl_override_creds(dentry->d_sb); err = notify_change(upperdentry, attr, NULL); + revert_creds(old_cred); if (!err) ovl_copyattr(upperdentry->d_inode, dentry->d_inode); inode_unlock(upperdentry->d_inode); @@ -102,9 +105,14 @@ static int ovl_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) { struct path realpath; + const struct cred *old_cred; + int err; ovl_path_real(dentry, &realpath); - return vfs_getattr(&realpath, stat); + old_cred = ovl_override_creds(dentry->d_sb); + err = vfs_getattr(&realpath, stat); + revert_creds(old_cred); + return err; } int ovl_permission(struct inode *inode, int mask) @@ -188,6 +196,8 @@ static const char *ovl_get_link(struct dentry *dentry, { struct dentry *realdentry; struct inode *realinode; + const struct cred *old_cred; + const char *p; if (!dentry) return ERR_PTR(-ECHILD); @@ -198,13 +208,18 @@ static const char *ovl_get_link(struct dentry *dentry, if (WARN_ON(!realinode->i_op->get_link)) return ERR_PTR(-EPERM); - return realinode->i_op->get_link(realdentry, realinode, done); + old_cred = ovl_override_creds(dentry->d_sb); + p = realinode->i_op->get_link(realdentry, realinode, done); + revert_creds(old_cred); + return p; } static int ovl_readlink(struct dentry *dentry, char __user *buf, int bufsiz) { struct path realpath; struct inode *realinode; + const struct cred *old_cred; + int err; ovl_path_real(dentry, &realpath); realinode = realpath.dentry->d_inode; @@ -214,10 +229,12 @@ static int ovl_readlink(struct dentry *dentry, char __user *buf, int bufsiz) touch_atime(&realpath); - return realinode->i_op->readlink(realpath.dentry, buf, bufsiz); + old_cred = ovl_override_creds(dentry->d_sb); + err = realinode->i_op->readlink(realpath.dentry, buf, bufsiz); + revert_creds(old_cred); + return err; } - static bool ovl_is_private_xattr(const char *name) { return strncmp(name, OVL_XATTR_PRE_NAME, OVL_XATTR_PRE_LEN) == 0; @@ -229,6 +246,7 @@ int ovl_setxattr(struct dentry *dentry, struct inode *inode, { int err; struct dentry *upperdentry; + const struct cred *old_cred; err = ovl_want_write(dentry); if (err) @@ -243,7 +261,9 @@ int ovl_setxattr(struct dentry *dentry, struct inode *inode, goto out_drop_write; upperdentry = ovl_dentry_upper(dentry); + old_cred = ovl_override_creds(dentry->d_sb); err = vfs_setxattr(upperdentry, name, value, size, flags); + revert_creds(old_cred); out_drop_write: ovl_drop_write(dentry); @@ -255,11 +275,16 @@ ssize_t ovl_getxattr(struct dentry *dentry, struct inode *inode, const char *name, void *value, size_t size) { struct dentry *realdentry = ovl_dentry_real(dentry); + ssize_t res; + const struct cred *old_cred; if (ovl_is_private_xattr(name)) return -ENODATA; - return vfs_getxattr(realdentry, name, value, size); + old_cred = ovl_override_creds(dentry->d_sb); + res = vfs_getxattr(realdentry, name, value, size); + revert_creds(old_cred); + return res; } ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size) @@ -267,8 +292,11 @@ ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size) struct dentry *realdentry = ovl_dentry_real(dentry); ssize_t res; int off; + const struct cred *old_cred; + old_cred = ovl_override_creds(dentry->d_sb); res = vfs_listxattr(realdentry, list, size); + revert_creds(old_cred); if (res <= 0 || size == 0) return res; @@ -295,6 +323,7 @@ int ovl_removexattr(struct dentry *dentry, const char *name) int err; struct path realpath; enum ovl_path_type type = ovl_path_real(dentry, &realpath); + const struct cred *old_cred; err = ovl_want_write(dentry); if (err) @@ -316,7 +345,9 @@ int ovl_removexattr(struct dentry *dentry, const char *name) ovl_path_upper(dentry, &realpath); } + old_cred = ovl_override_creds(dentry->d_sb); err = vfs_removexattr(realpath.dentry, name); + revert_creds(old_cred); out_drop_write: ovl_drop_write(dentry); out: @@ -326,6 +357,8 @@ out: struct posix_acl *ovl_get_acl(struct inode *inode, int type) { struct inode *realinode = ovl_inode_real(inode); + const struct cred *old_cred; + struct posix_acl *acl; if (!IS_POSIXACL(realinode)) return NULL; @@ -333,7 +366,11 @@ struct posix_acl *ovl_get_acl(struct inode *inode, int type) if (!realinode->i_op->get_acl) return NULL; - return realinode->i_op->get_acl(realinode, type); + old_cred = ovl_override_creds(inode->i_sb); + acl = realinode->i_op->get_acl(realinode, type); + revert_creds(old_cred); + + return acl; } static bool ovl_open_need_copy_up(int flags, enum ovl_path_type type, |