diff options
| -rw-r--r-- | security/tomoyo/file.c | 12 | ||||
| -rw-r--r-- | security/tomoyo/realpath.c | 222 |
2 files changed, 180 insertions, 54 deletions
diff --git a/security/tomoyo/file.c b/security/tomoyo/file.c index 323ddc73a125..8410f28a35e0 100644 --- a/security/tomoyo/file.c +++ b/security/tomoyo/file.c @@ -712,7 +712,7 @@ int tomoyo_path_number_perm(const u8 type, struct path *path, int idx; if (tomoyo_init_request_info(&r, NULL, tomoyo_pn2mac[type]) - == TOMOYO_CONFIG_DISABLED || !path->mnt || !path->dentry) + == TOMOYO_CONFIG_DISABLED || !path->dentry) return 0; idx = tomoyo_read_lock(); if (!tomoyo_get_realpath(&buf, path)) @@ -753,8 +753,6 @@ int tomoyo_check_open_permission(struct tomoyo_domain_info *domain, struct tomoyo_request_info r; int idx; - if (!path->mnt) - return 0; buf.name = NULL; r.mode = TOMOYO_CONFIG_DISABLED; idx = tomoyo_read_lock(); @@ -798,8 +796,6 @@ int tomoyo_path_perm(const u8 operation, struct path *path) bool is_enforce; int idx; - if (!path->mnt) - return 0; if (tomoyo_init_request_info(&r, NULL, tomoyo_p2mac[operation]) == TOMOYO_CONFIG_DISABLED) return 0; @@ -842,8 +838,7 @@ int tomoyo_mkdev_perm(const u8 operation, struct path *path, struct tomoyo_path_info buf; int idx; - if (!path->mnt || - tomoyo_init_request_info(&r, NULL, tomoyo_pnnn2mac[operation]) + if (tomoyo_init_request_info(&r, NULL, tomoyo_pnnn2mac[operation]) == TOMOYO_CONFIG_DISABLED) return 0; idx = tomoyo_read_lock(); @@ -884,8 +879,7 @@ int tomoyo_path2_perm(const u8 operation, struct path *path1, struct tomoyo_request_info r; int idx; - if (!path1->mnt || !path2->mnt || - tomoyo_init_request_info(&r, NULL, tomoyo_pp2mac[operation]) + if (tomoyo_init_request_info(&r, NULL, tomoyo_pp2mac[operation]) == TOMOYO_CONFIG_DISABLED) return 0; buf1.name = NULL; diff --git a/security/tomoyo/realpath.c b/security/tomoyo/realpath.c index d1e05b047715..1a785777118b 100644 --- a/security/tomoyo/realpath.c +++ b/security/tomoyo/realpath.c @@ -70,6 +70,161 @@ char *tomoyo_encode(const char *str) } /** + * tomoyo_get_absolute_path - Get the path of a dentry but ignores chroot'ed root. + * + * @path: Pointer to "struct path". + * @buffer: Pointer to buffer to return value in. + * @buflen: Sizeof @buffer. + * + * Returns the buffer on success, an error code otherwise. + * + * If dentry is a directory, trailing '/' is appended. + */ +static char *tomoyo_get_absolute_path(struct path *path, char * const buffer, + const int buflen) +{ + char *pos = ERR_PTR(-ENOMEM); + if (buflen >= 256) { + struct path ns_root = { }; + /* go to whatever namespace root we are under */ + pos = __d_path(path, &ns_root, buffer, buflen - 1); + if (!IS_ERR(pos) && *pos == '/' && pos[1]) { + struct inode *inode = path->dentry->d_inode; + if (inode && S_ISDIR(inode->i_mode)) { + buffer[buflen - 2] = '/'; + buffer[buflen - 1] = '\0'; + } + } + } + return pos; +} + +/** + * tomoyo_get_dentry_path - Get the path of a dentry. + * + * @dentry: Pointer to "struct dentry". + * @buffer: Pointer to buffer to return value in. + * @buflen: Sizeof @buffer. + * + * Returns the buffer on success, an error code otherwise. + * + * If dentry is a directory, trailing '/' is appended. + */ +static char *tomoyo_get_dentry_path(struct dentry *dentry, char * const buffer, + const int buflen) +{ + char *pos = ERR_PTR(-ENOMEM); + if (buflen >= 256) { + pos = dentry_path_raw(dentry, buffer, buflen - 1); + if (!IS_ERR(pos) && *pos == '/' && pos[1]) { + struct inode *inode = dentry->d_inode; + if (inode && S_ISDIR(inode->i_mode)) { + buffer[buflen - 2] = '/'; + buffer[buflen - 1] = '\0'; + } + } + } + return pos; +} + +/** + * tomoyo_get_local_path - Get the path of a dentry. + * + * @dentry: Pointer to "struct dentry". + * @buffer: Pointer to buffer to return value in. + * @buflen: Sizeof @buffer. + * + * Returns the buffer on success, an error code otherwise. + */ +static char *tomoyo_get_local_path(struct dentry *dentry, char * const buffer, + const int buflen) +{ + struct super_block *sb = dentry->d_sb; + char *pos = tomoyo_get_dentry_path(dentry, buffer, buflen); + if (IS_ERR(pos)) + return pos; + /* Convert from $PID to self if $PID is current thread. */ + if (sb->s_magic == PROC_SUPER_MAGIC && *pos == '/') { + char *ep; + const pid_t pid = (pid_t) simple_strtoul(pos + 1, &ep, 10); + if (*ep == '/' && pid && pid == + task_tgid_nr_ns(current, sb->s_fs_info)) { + pos = ep - 5; + if (pos < buffer) + goto out; + memmove(pos, "/self", 5); + } + goto prepend_filesystem_name; + } + /* Use filesystem name for unnamed devices. */ + if (!MAJOR(sb->s_dev)) + goto prepend_filesystem_name; + { + struct inode *inode = sb->s_root->d_inode; + /* + * Use filesystem name if filesystem does not support rename() + * operation. + */ + if (inode->i_op && !inode->i_op->rename) + goto prepend_filesystem_name; + } + /* Prepend device name. */ + { + char name[64]; + int name_len; + const dev_t dev = sb->s_dev; + name[sizeof(name) - 1] = '\0'; + snprintf(name, sizeof(name) - 1, "dev(%u,%u):", MAJOR(dev), + MINOR(dev)); + name_len = strlen(name); + pos -= name_len; + if (pos < buffer) + goto out; + memmove(pos, name, name_len); + return pos; + } + /* Prepend filesystem name. */ +prepend_filesystem_name: + { + const char *name = sb->s_type->name; + const int name_len = strlen(name); + pos -= name_len + 1; + if (pos < buffer) + goto out; + memmove(pos, name, name_len); + pos[name_len] = ':'; + } + return pos; +out: + return ERR_PTR(-ENOMEM); +} + +/** + * tomoyo_get_socket_name - Get the name of a socket. + * + * @path: Pointer to "struct path". + * @buffer: Pointer to buffer to return value in. + * @buflen: Sizeof @buffer. + * + * Returns the buffer. + */ +static char *tomoyo_get_socket_name(struct path *path, char * const buffer, + const int buflen) +{ + struct inode *inode = path->dentry->d_inode; + struct socket *sock = inode ? SOCKET_I(inode) : NULL; + struct sock *sk = sock ? sock->sk : NULL; + if (sk) { + snprintf(buffer, buflen, "socket:[family=%u:type=%u:" + "protocol=%u]", sk->sk_family, sk->sk_type, + sk->sk_protocol); + } else { + snprintf(buffer, buflen, "socket:[unknown]"); + } + return buffer; +} + +/** * tomoyo_realpath_from_path - Returns realpath(3) of the given pathname but ignores chroot'ed root. * * @path: Pointer to "struct path". @@ -90,55 +245,42 @@ char *tomoyo_realpath_from_path(struct path *path) char *name = NULL; unsigned int buf_len = PAGE_SIZE / 2; struct dentry *dentry = path->dentry; - bool is_dir; + struct super_block *sb; if (!dentry) return NULL; - is_dir = dentry->d_inode && S_ISDIR(dentry->d_inode->i_mode); + sb = dentry->d_sb; while (1) { - struct path ns_root = { .mnt = NULL, .dentry = NULL }; char *pos; + struct inode *inode; buf_len <<= 1; kfree(buf); buf = kmalloc(buf_len, GFP_NOFS); if (!buf) break; + /* To make sure that pos is '\0' terminated. */ + buf[buf_len - 1] = '\0'; /* Get better name for socket. */ - if (dentry->d_sb && dentry->d_sb->s_magic == SOCKFS_MAGIC) { - struct inode *inode = dentry->d_inode; - struct socket *sock = inode ? SOCKET_I(inode) : NULL; - struct sock *sk = sock ? sock->sk : NULL; - if (sk) { - snprintf(buf, buf_len - 1, "socket:[family=%u:" - "type=%u:protocol=%u]", sk->sk_family, - sk->sk_type, sk->sk_protocol); - } else { - snprintf(buf, buf_len - 1, "socket:[unknown]"); - } - name = tomoyo_encode(buf); - break; + if (sb->s_magic == SOCKFS_MAGIC) { + pos = tomoyo_get_socket_name(path, buf, buf_len - 1); + goto encode; } - /* For "socket:[\$]" and "pipe:[\$]". */ + /* For "pipe:[\$]". */ if (dentry->d_op && dentry->d_op->d_dname) { pos = dentry->d_op->d_dname(dentry, buf, buf_len - 1); - if (IS_ERR(pos)) - continue; - name = tomoyo_encode(pos); - break; - } - /* If we don't have a vfsmount, we can't calculate. */ - if (!path->mnt) - break; - /* go to whatever namespace root we are under */ - pos = __d_path(path, &ns_root, buf, buf_len); - /* Prepend "/proc" prefix if using internal proc vfs mount. */ - if (!IS_ERR(pos) && (path->mnt->mnt_flags & MNT_INTERNAL) && - (path->mnt->mnt_sb->s_magic == PROC_SUPER_MAGIC)) { - pos -= 5; - if (pos >= buf) - memcpy(pos, "/proc", 5); - else - pos = ERR_PTR(-ENOMEM); + goto encode; } + inode = sb->s_root->d_inode; + /* + * Get local name for filesystems without rename() operation + * or dentry without vfsmount. + */ + if (!path->mnt || (inode->i_op && !inode->i_op->rename)) + pos = tomoyo_get_local_path(path->dentry, buf, + buf_len - 1); + /* Get absolute name for the rest. */ + else + pos = tomoyo_get_absolute_path(path, buf, buf_len - 1); +encode: if (IS_ERR(pos)) continue; name = tomoyo_encode(pos); @@ -147,16 +289,6 @@ char *tomoyo_realpath_from_path(struct path *path) kfree(buf); if (!name) tomoyo_warn_oom(__func__); - else if (is_dir && *name) { - /* Append trailing '/' if dentry is a directory. */ - char *pos = name + strlen(name) - 1; - if (*pos != '/') - /* - * This is OK because tomoyo_encode() reserves space - * for appending "/". - */ - *++pos = '/'; - } return name; } |