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| author | Seth Forshee <seth.forshee@canonical.com> | 2017-01-26 21:33:46 +0100 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2017-02-01 06:17:05 +0100 |
| commit | 1328c727004d432bbdfba0ffa02a166df04c7305 (patch) | |
| tree | 93c51d5133b18cfdc6660669e15e266133360d2a /fs/namei.c | |
| parent | proc: Better ownership of files for non-dumpable tasks in user namespaces (diff) | |
| download | linux-1328c727004d432bbdfba0ffa02a166df04c7305.tar.xz linux-1328c727004d432bbdfba0ffa02a166df04c7305.zip | |
vfs: open() with O_CREAT should not create inodes with unknown ids
may_create() rejects creation of inodes with ids which lack a
mapping into s_user_ns. However for O_CREAT may_o_create() is
is used instead. Add a similar check there.
Fixes: 036d523641c6 ("vfs: Don't create inodes with a uid or gid unknown to the vfs")
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'fs/namei.c')
| -rw-r--r-- | fs/namei.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/fs/namei.c b/fs/namei.c index ad74877e1442..6fa3e9138fe4 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2941,10 +2941,16 @@ static inline int open_to_namei_flags(int flag) static int may_o_create(const struct path *dir, struct dentry *dentry, umode_t mode) { + struct user_namespace *s_user_ns; int error = security_path_mknod(dir, dentry, mode, 0); if (error) return error; + s_user_ns = dir->dentry->d_sb->s_user_ns; + if (!kuid_has_mapping(s_user_ns, current_fsuid()) || + !kgid_has_mapping(s_user_ns, current_fsgid())) + return -EOVERFLOW; + error = inode_permission(dir->dentry->d_inode, MAY_WRITE | MAY_EXEC); if (error) return error; |