diff options
author | Chao Yu <yuchao0@huawei.com> | 2019-07-17 17:06:11 +0800 |
---|---|---|
committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2019-08-23 07:57:15 -0700 |
commit | 4507847c86bfc64e9bdce941a0f707560d3df98a (patch) | |
tree | 7e76cf839e82f3fdbf71f09943f0feb7e68bb7de /fs/f2fs/file.c | |
parent | 899fee36fac07e49bb969e3f214e572eecb14f00 (diff) |
f2fs: support FS_IOC_{GET,SET}FSLABEL
Support two generic fs ioctls FS_IOC_{GET,SET}FSLABEL, letting
f2fs pass generic/492 testcase.
Fixes were made by Eric where:
- f2fs: fix buffer overruns in FS_IOC_{GET, SET}FSLABEL
utf16s_to_utf8s() and utf8s_to_utf16s() take the number of characters,
not the number of bytes.
- f2fs: fix copying too many bytes in FS_IOC_SETFSLABEL
Userspace provides a null-terminated string, so don't assume that the
full FSLABEL_MAX bytes can always be copied.
- f2fs: add missing authorization check in FS_IOC_SETFSLABEL
FS_IOC_SETFSLABEL modifies the filesystem superblock, so it shouldn't be
allowed to regular users. Require CAP_SYS_ADMIN, like xfs and btrfs do.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/file.c')
-rw-r--r-- | fs/f2fs/file.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index b1f38f2795bc..344e0bd638e5 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -20,6 +20,7 @@ #include <linux/uio.h> #include <linux/uuid.h> #include <linux/file.h> +#include <linux/nls.h> #include "f2fs.h" #include "node.h" @@ -3081,6 +3082,68 @@ static int f2fs_ioc_resize_fs(struct file *filp, unsigned long arg) return ret; } +static int f2fs_get_volume_name(struct file *filp, unsigned long arg) +{ + struct inode *inode = file_inode(filp); + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + char *vbuf; + int count; + int err = 0; + + vbuf = f2fs_kzalloc(sbi, MAX_VOLUME_NAME, GFP_KERNEL); + if (!vbuf) + return -ENOMEM; + + down_read(&sbi->sb_lock); + count = utf16s_to_utf8s(sbi->raw_super->volume_name, + ARRAY_SIZE(sbi->raw_super->volume_name), + UTF16_LITTLE_ENDIAN, vbuf, MAX_VOLUME_NAME); + up_read(&sbi->sb_lock); + + if (copy_to_user((char __user *)arg, vbuf, + min(FSLABEL_MAX, count))) + err = -EFAULT; + + kvfree(vbuf); + return err; +} + +static int f2fs_set_volume_name(struct file *filp, unsigned long arg) +{ + struct inode *inode = file_inode(filp); + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + char *vbuf; + int err = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + vbuf = strndup_user((const char __user *)arg, FSLABEL_MAX); + if (IS_ERR(vbuf)) + return PTR_ERR(vbuf); + + err = mnt_want_write_file(filp); + if (err) + goto out; + + down_write(&sbi->sb_lock); + + memset(sbi->raw_super->volume_name, 0, + sizeof(sbi->raw_super->volume_name)); + utf8s_to_utf16s(vbuf, strlen(vbuf), UTF16_LITTLE_ENDIAN, + sbi->raw_super->volume_name, + ARRAY_SIZE(sbi->raw_super->volume_name)); + + err = f2fs_commit_super(sbi, false); + + up_write(&sbi->sb_lock); + + mnt_drop_write_file(filp); +out: + kfree(vbuf); + return err; +} + long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { int ret; @@ -3144,6 +3207,10 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) return f2fs_ioc_precache_extents(filp, arg); case F2FS_IOC_RESIZE_FS: return f2fs_ioc_resize_fs(filp, arg); + case F2FS_IOC_GET_VOLUME_NAME: + return f2fs_get_volume_name(filp, arg); + case F2FS_IOC_SET_VOLUME_NAME: + return f2fs_set_volume_name(filp, arg); default: return -ENOTTY; } @@ -3253,6 +3320,8 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) case F2FS_IOC_SET_PIN_FILE: case F2FS_IOC_PRECACHE_EXTENTS: case F2FS_IOC_RESIZE_FS: + case F2FS_IOC_GET_VOLUME_NAME: + case F2FS_IOC_SET_VOLUME_NAME: break; default: return -ENOIOCTLCMD; |