xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

coda: Restrict coda messages to the initial user namespace

Browse Source 
Remove the slight chance that uids and gids in coda messages will be
interpreted in the wrong user namespace.

- Only allow processes in the initial user namespace to open the coda
  character device to communicate with coda filesystems.
- Explicitly convert the uids in the coda header into the initial user
  namespace.
- In coda_vattr_to_attr make kuids and kgids from the initial user
  namespace uids and gids in struct coda_vattr that just came from
  userspace.
- In coda_iattr_to_vattr convert kuids and kgids into uids and gids
  in the intial user namespace and store them in struct coda_vattr for
  sending to coda userspace programs.

Nothing needs to be changed with mounts as coda does not support
being mounted in anything other than the initial user namespace.

Cc: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman
2013-01-30 19:21:14 -08:00
parent 9fd973e085
commit d83f5901bc
4 changed files with 11 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
fs/coda/coda_linux.c
View File

@@ -100,9 +100,9 @@ void coda_vattr_to_iattr(struct inode *inode, struct coda_vattr *attr)
if (attr->va_mode != (u_short) -1)
inode->i_mode = attr->va_mode | inode_type;
if (attr->va_uid != -1)
inode->i_uid = (uid_t) attr->va_uid;
inode->i_uid = make_kuid(&init_user_ns, (uid_t) attr->va_uid);
if (attr->va_gid != -1)
inode->i_gid = (gid_t) attr->va_gid;
inode->i_gid = make_kgid(&init_user_ns, (gid_t) attr->va_gid);
if (attr->va_nlink != -1)
set_nlink(inode, attr->va_nlink);
if (attr->va_size != -1)
@@ -171,10 +171,10 @@ void coda_iattr_to_vattr(struct iattr *iattr, struct coda_vattr *vattr)
vattr->va_mode = iattr->ia_mode;
}
if ( valid & ATTR_UID ) {
vattr->va_uid = (vuid_t) iattr->ia_uid;
vattr->va_uid = (vuid_t) from_kuid(&init_user_ns, iattr->ia_uid);
}
if ( valid & ATTR_GID ) {
vattr->va_gid = (vgid_t) iattr->ia_gid;
vattr->va_gid = (vgid_t) from_kgid(&init_user_ns, iattr->ia_gid);
}
if ( valid & ATTR_SIZE ) {
vattr->va_size = iattr->ia_size;