diff options
| author | Eric W. Biederman <ebiederm@xmission.com> | 2018-05-23 15:24:18 -0500 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2018-05-24 11:56:43 -0500 |
| commit | 55956b59df336f6738da916dbb520b6e37df9fbd (patch) | |
| tree | 092af72e9a7cb4ac14ddd1941cf82b6c269e0a1b /fs | |
| parent | 593d1ce854dff93b3c9066e897192eb676b09c46 (diff) | |
| download | lwn-55956b59df336f6738da916dbb520b6e37df9fbd.tar.gz lwn-55956b59df336f6738da916dbb520b6e37df9fbd.zip | |
vfs: Allow userns root to call mknod on owned filesystems.
These filesystems already always set SB_I_NODEV so mknod will not be
useful for gaining control of any devices no matter their permissions.
This will allow overlayfs and applications like to fakeroot to use
device nodes to represent things on disk.
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/namei.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/namei.c b/fs/namei.c index 942c1f096f6b..20335896dcce 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3679,7 +3679,8 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) if (error) return error; - if ((S_ISCHR(mode) || S_ISBLK(mode)) && !capable(CAP_MKNOD)) + if ((S_ISCHR(mode) || S_ISBLK(mode)) && + !ns_capable(dentry->d_sb->s_user_ns, CAP_MKNOD)) return -EPERM; if (!dir->i_op->mknod) |