diff options
Diffstat (limited to 'fs/namespace.c')
| -rw-r--r-- | fs/namespace.c | 77 |
1 files changed, 47 insertions, 30 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 7230787d18b..bdc3cb4fd22 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1640,7 +1640,7 @@ static int do_new_mount(struct path *path, char *type, int flags, { struct vfsmount *mnt; - if (!type || !memchr(type, 0, PAGE_SIZE)) + if (!type) return -EINVAL; /* we need capabilities... */ @@ -1871,6 +1871,23 @@ int copy_mount_options(const void __user * data, unsigned long *where) return 0; } +int copy_mount_string(const void __user *data, char **where) +{ + char *tmp; + + if (!data) { + *where = NULL; + return 0; + } + + tmp = strndup_user(data, PAGE_SIZE); + if (IS_ERR(tmp)) + return PTR_ERR(tmp); + + *where = tmp; + return 0; +} + /* * Flags is a 32-bit value that allows up to 31 non-fs dependent flags to * be given to the mount() call (ie: read-only, no-dev, no-suid etc). @@ -1900,8 +1917,6 @@ long do_mount(char *dev_name, char *dir_name, char *type_page, if (!dir_name || !*dir_name || !memchr(dir_name, 0, PAGE_SIZE)) return -EINVAL; - if (dev_name && !memchr(dev_name, 0, PAGE_SIZE)) - return -EINVAL; if (data_page) ((char *)data_page)[PAGE_SIZE - 1] = 0; @@ -2070,40 +2085,42 @@ EXPORT_SYMBOL(create_mnt_ns); SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name, char __user *, type, unsigned long, flags, void __user *, data) { - int retval; + int ret; + char *kernel_type; + char *kernel_dir; + char *kernel_dev; unsigned long data_page; - unsigned long type_page; - unsigned long dev_page; - char *dir_page; - retval = copy_mount_options(type, &type_page); - if (retval < 0) - return retval; + ret = copy_mount_string(type, &kernel_type); + if (ret < 0) + goto out_type; - dir_page = getname(dir_name); - retval = PTR_ERR(dir_page); - if (IS_ERR(dir_page)) - goto out1; + kernel_dir = getname(dir_name); + if (IS_ERR(kernel_dir)) { + ret = PTR_ERR(kernel_dir); + goto out_dir; + } - retval = copy_mount_options(dev_name, &dev_page); - if (retval < 0) - goto out2; + ret = copy_mount_string(dev_name, &kernel_dev); + if (ret < 0) + goto out_dev; - retval = copy_mount_options(data, &data_page); - if (retval < 0) - goto out3; + ret = copy_mount_options(data, &data_page); + if (ret < 0) + goto out_data; - retval = do_mount((char *)dev_page, dir_page, (char *)type_page, - flags, (void *)data_page); - free_page(data_page); + ret = do_mount(kernel_dev, kernel_dir, kernel_type, flags, + (void *) data_page); -out3: - free_page(dev_page); -out2: - putname(dir_page); -out1: - free_page(type_page); - return retval; + free_page(data_page); +out_data: + kfree(kernel_dev); +out_dev: + putname(kernel_dir); +out_dir: + kfree(kernel_type); +out_type: + return ret; } /* |