diff options
| author | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-21 14:19:26 +0100 |
|---|---|---|
| committer | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-24 14:27:16 +0100 |
| commit | 2f221d6f7b881d95de1f356a3097d755ab1e47d4 (patch) | |
| tree | 3d136e3ade1492f1ab59e09546ffa6f2d723f76d /fs/proc | |
| parent | 21cb47be6fb9ece7e6ee63f6780986faa384a77c (diff) | |
attr: handle idmapped mounts
When file attributes are changed most filesystems rely on the
setattr_prepare(), setattr_copy(), and notify_change() helpers for
initialization and permission checking. Let them handle idmapped mounts.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped mounts. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Helpers that perform checks on the ia_uid and ia_gid fields in struct
iattr assume that ia_uid and ia_gid are intended values and have already
been mapped correctly at the userspace-kernelspace boundary as we
already do today. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-8-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Diffstat (limited to 'fs/proc')
| -rw-r--r-- | fs/proc/base.c | 4 | ||||
| -rw-r--r-- | fs/proc/generic.c | 4 | ||||
| -rw-r--r-- | fs/proc/proc_sysctl.c | 4 |
3 files changed, 6 insertions, 6 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index b4ec9293625e..bb4e63a3684f 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -693,11 +693,11 @@ int proc_setattr(struct dentry *dentry, struct iattr *attr) if (attr->ia_valid & ATTR_MODE) return -EPERM; - error = setattr_prepare(dentry, attr); + error = setattr_prepare(&init_user_ns, dentry, attr); if (error) return error; - setattr_copy(inode, attr); + setattr_copy(&init_user_ns, inode, attr); mark_inode_dirty(inode); return 0; } diff --git a/fs/proc/generic.c b/fs/proc/generic.c index 6c0a05f55d6b..6d4fabab8aa7 100644 --- a/fs/proc/generic.c +++ b/fs/proc/generic.c @@ -121,11 +121,11 @@ static int proc_notify_change(struct dentry *dentry, struct iattr *iattr) struct proc_dir_entry *de = PDE(inode); int error; - error = setattr_prepare(dentry, iattr); + error = setattr_prepare(&init_user_ns, dentry, iattr); if (error) return error; - setattr_copy(inode, iattr); + setattr_copy(&init_user_ns, inode, iattr); mark_inode_dirty(inode); proc_set_user(de, inode->i_uid, inode->i_gid); diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index 317899222d7f..ec67dbc1f705 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -821,11 +821,11 @@ static int proc_sys_setattr(struct dentry *dentry, struct iattr *attr) if (attr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)) return -EPERM; - error = setattr_prepare(dentry, attr); + error = setattr_prepare(&init_user_ns, dentry, attr); if (error) return error; - setattr_copy(inode, attr); + setattr_copy(&init_user_ns, inode, attr); mark_inode_dirty(inode); return 0; } |