Enable generic ioctls to handle idmapped mounts by passing down the mount's
user namespace.

Cc: Christoph Hellwig <h...@lst.de>
Cc: David Howells <dhowe...@redhat.com>
Cc: Al Viro <v...@zeniv.linux.org.uk>
Cc: linux-fsde...@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brau...@ubuntu.com>
---
/* v2 */
patch introduced
---
 fs/remap_range.c   | 7 +++++--
 fs/verity/enable.c | 2 +-
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/fs/remap_range.c b/fs/remap_range.c
index 9e5b27641756..fe7f07228462 100644
--- a/fs/remap_range.c
+++ b/fs/remap_range.c
@@ -432,13 +432,16 @@ EXPORT_SYMBOL(vfs_clone_file_range);
 /* Check whether we are allowed to dedupe the destination file */
 static bool allow_file_dedupe(struct file *file)
 {
+       struct user_namespace *user_ns = mnt_user_ns(file->f_path.mnt);
+       struct inode *inode = file_inode(file);
+
        if (capable(CAP_SYS_ADMIN))
                return true;
        if (file->f_mode & FMODE_WRITE)
                return true;
-       if (uid_eq(current_fsuid(), file_inode(file)->i_uid))
+       if (uid_eq(current_fsuid(), i_uid_into_mnt(user_ns, inode)))
                return true;
-       if (!inode_permission(&init_user_ns, file_inode(file), MAY_WRITE))
+       if (!inode_permission(user_ns, inode, MAY_WRITE))
                return true;
        return false;
 }
diff --git a/fs/verity/enable.c b/fs/verity/enable.c
index 7449ef0050f4..8b9ea0f0850f 100644
--- a/fs/verity/enable.c
+++ b/fs/verity/enable.c
@@ -369,7 +369,7 @@ int fsverity_ioctl_enable(struct file *filp, const void 
__user *uarg)
         * has verity enabled, and to stabilize the data being hashed.
         */
 
-       err = inode_permission(&init_user_ns, inode, MAY_WRITE);
+       err = inode_permission(mnt_user_ns(filp->f_path.mnt), inode, MAY_WRITE);
        if (err)
                return err;
 
-- 
2.29.2

--
Linux-audit mailing list
Linux-audit@redhat.com
https://www.redhat.com/mailman/listinfo/linux-audit

Reply via email to