diff options
Diffstat (limited to 'security/commoncap.c')
| -rw-r--r-- | security/commoncap.c | 57 |
1 files changed, 30 insertions, 27 deletions
diff --git a/security/commoncap.c b/security/commoncap.c index 01b68f9311ca..b70ba98fbd1c 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -305,24 +305,24 @@ int cap_inode_need_killpriv(struct dentry *dentry) /** * cap_inode_killpriv - Erase the security markings on an inode * - * @mnt_userns: user namespace of the mount the inode was found from + * @idmap: idmap of the mount the inode was found from * @dentry: The inode/dentry to alter * * Erase the privilege-enhancing security markings on an inode. * - * If the inode has been found through an idmapped mount the user namespace of - * the vfsmount must be passed through @mnt_userns. This function will then - * take care to map the inode according to @mnt_userns before checking + * If the inode has been found through an idmapped mount the idmap of + * the vfsmount must be passed through @idmap. This function will then + * take care to map the inode according to @idmap before checking * permissions. On non-idmapped mounts or if permission checking is to be - * performed on the raw inode simply passs init_user_ns. + * performed on the raw inode simply passs @nop_mnt_idmap. * * Return: 0 if successful, -ve on error. */ -int cap_inode_killpriv(struct user_namespace *mnt_userns, struct dentry *dentry) +int cap_inode_killpriv(struct mnt_idmap *idmap, struct dentry *dentry) { int error; - error = __vfs_removexattr(mnt_userns, dentry, XATTR_NAME_CAPS); + error = __vfs_removexattr(idmap, dentry, XATTR_NAME_CAPS); if (error == -EOPNOTSUPP) error = 0; return error; @@ -511,7 +511,7 @@ static bool validheader(size_t size, const struct vfs_cap_data *cap) /** * cap_convert_nscap - check vfs caps * - * @mnt_userns: user namespace of the mount the inode was found from + * @idmap: idmap of the mount the inode was found from * @dentry: used to retrieve inode to check permissions on * @ivalue: vfs caps value which may be modified by this function * @size: size of @ivalue @@ -519,15 +519,15 @@ static bool validheader(size_t size, const struct vfs_cap_data *cap) * User requested a write of security.capability. If needed, update the * xattr to change from v2 to v3, or to fixup the v3 rootid. * - * If the inode has been found through an idmapped mount the user namespace of - * the vfsmount must be passed through @mnt_userns. This function will then - * take care to map the inode according to @mnt_userns before checking + * If the inode has been found through an idmapped mount the idmap of + * the vfsmount must be passed through @idmap. This function will then + * take care to map the inode according to @idmap before checking * permissions. On non-idmapped mounts or if permission checking is to be - * performed on the raw inode simply passs init_user_ns. + * performed on the raw inode simply passs @nop_mnt_idmap. * * Return: On success, return the new size; on error, return < 0. */ -int cap_convert_nscap(struct user_namespace *mnt_userns, struct dentry *dentry, +int cap_convert_nscap(struct mnt_idmap *idmap, struct dentry *dentry, const void **ivalue, size_t size) { struct vfs_ns_cap_data *nscap; @@ -537,6 +537,7 @@ int cap_convert_nscap(struct user_namespace *mnt_userns, struct dentry *dentry, struct inode *inode = d_backing_inode(dentry); struct user_namespace *task_ns = current_user_ns(), *fs_ns = inode->i_sb->s_user_ns; + struct user_namespace *mnt_userns = mnt_idmap_owner(idmap); kuid_t rootid; vfsuid_t vfsrootid; size_t newsize; @@ -547,7 +548,7 @@ int cap_convert_nscap(struct user_namespace *mnt_userns, struct dentry *dentry, return -EINVAL; if (!capable_wrt_inode_uidgid(mnt_userns, inode, CAP_SETFCAP)) return -EPERM; - if (size == XATTR_CAPS_SZ_2 && (mnt_userns == fs_ns)) + if (size == XATTR_CAPS_SZ_2 && (idmap == &nop_mnt_idmap)) if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP)) /* user is privileged, just write the v2 */ return size; @@ -627,19 +628,19 @@ static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps, /** * get_vfs_caps_from_disk - retrieve vfs caps from disk * - * @mnt_userns: user namespace of the mount the inode was found from + * @idmap: idmap of the mount the inode was found from * @dentry: dentry from which @inode is retrieved * @cpu_caps: vfs capabilities * * Extract the on-exec-apply capability sets for an executable file. * - * If the inode has been found through an idmapped mount the user namespace of - * the vfsmount must be passed through @mnt_userns. This function will then - * take care to map the inode according to @mnt_userns before checking + * If the inode has been found through an idmapped mount the idmap of + * the vfsmount must be passed through @idmap. This function will then + * take care to map the inode according to @idmap before checking * permissions. On non-idmapped mounts or if permission checking is to be - * performed on the raw inode simply passs init_user_ns. + * performed on the raw inode simply passs @nop_mnt_idmap. */ -int get_vfs_caps_from_disk(struct user_namespace *mnt_userns, +int get_vfs_caps_from_disk(struct mnt_idmap *idmap, const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps) { @@ -652,6 +653,7 @@ int get_vfs_caps_from_disk(struct user_namespace *mnt_userns, kuid_t rootkuid; vfsuid_t rootvfsuid; struct user_namespace *fs_ns; + struct user_namespace *mnt_userns = mnt_idmap_owner(idmap); memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data)); @@ -748,7 +750,7 @@ static int get_file_caps(struct linux_binprm *bprm, struct file *file, if (!current_in_userns(file->f_path.mnt->mnt_sb->s_user_ns)) return 0; - rc = get_vfs_caps_from_disk(file_mnt_user_ns(file), + rc = get_vfs_caps_from_disk(file_mnt_idmap(file), file->f_path.dentry, &vcaps); if (rc < 0) { if (rc == -EINVAL) @@ -1017,26 +1019,27 @@ int cap_inode_setxattr(struct dentry *dentry, const char *name, /** * cap_inode_removexattr - Determine whether an xattr may be removed * - * @mnt_userns: User namespace of the mount the inode was found from + * @idmap: idmap of the mount the inode was found from * @dentry: The inode/dentry being altered * @name: The name of the xattr to be changed * * Determine whether an xattr may be removed from an inode, returning 0 if * permission is granted, -ve if denied. * - * If the inode has been found through an idmapped mount the user namespace of - * the vfsmount must be passed through @mnt_userns. This function will then - * take care to map the inode according to @mnt_userns before checking + * If the inode has been found through an idmapped mount the idmap of + * the vfsmount must be passed through @idmap. This function will then + * take care to map the inode according to @idmap before checking * permissions. On non-idmapped mounts or if permission checking is to be - * performed on the raw inode simply passs init_user_ns. + * performed on the raw inode simply pass @nop_mnt_idmap. * * This is used to make sure security xattrs don't get removed by those who * aren't privileged to remove them. */ -int cap_inode_removexattr(struct user_namespace *mnt_userns, +int cap_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name) { struct user_namespace *user_ns = dentry->d_sb->s_user_ns; + struct user_namespace *mnt_userns = mnt_idmap_owner(idmap); /* Ignore non-security xattrs */ if (strncmp(name, XATTR_SECURITY_PREFIX, |