diff options
author | Tycho Andersen <tycho@tycho.pizza> | 2021-01-21 14:19:28 +0100 |
---|---|---|
committer | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-24 14:27:17 +0100 |
commit | c7c7a1a18af4c3bb7749d33e3df3acdf0a95bbb5 (patch) | |
tree | 70987010043f447700ed119e1b05b8fb429af5dd /fs/ecryptfs | |
parent | e65ce2a50cf6af216bea6fd80d771fcbb4c0aaa1 (diff) |
xattr: handle idmapped mounts
When interacting with extended attributes the vfs verifies that the
caller is privileged over the inode with which the extended attribute is
associated. For posix access and posix default extended attributes a uid
or gid can be stored on-disk. Let the functions handle posix extended
attributes on idmapped mounts. If the inode is accessed through an
idmapped mount we need to map it according to the mount's user
namespace. Afterwards the checks are identical to non-idmapped mounts.
This has no effect for e.g. security xattrs since they don't store uids
or gids and don't perform permission checks on them like posix acls do.
Link: https://lore.kernel.org/r/20210121131959.646623-10-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>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Tycho Andersen <tycho@tycho.pizza>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Diffstat (limited to 'fs/ecryptfs')
-rw-r--r-- | fs/ecryptfs/crypto.c | 4 | ||||
-rw-r--r-- | fs/ecryptfs/inode.c | 5 | ||||
-rw-r--r-- | fs/ecryptfs/mmap.c | 4 |
3 files changed, 7 insertions, 6 deletions
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index 0681540c48d9..943e523f4c9d 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -1110,8 +1110,8 @@ ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry, } inode_lock(lower_inode); - rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME, - page_virt, size, 0); + rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode, + ECRYPTFS_XATTR_NAME, page_virt, size, 0); if (!rc && ecryptfs_inode) fsstack_copy_attr_all(ecryptfs_inode, lower_inode); inode_unlock(lower_inode); diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index ac6472a82567..b9ccc4085d46 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -1024,7 +1024,8 @@ ecryptfs_setxattr(struct dentry *dentry, struct inode *inode, rc = -EOPNOTSUPP; goto out; } - rc = vfs_setxattr(lower_dentry, name, value, size, flags); + rc = vfs_setxattr(&init_user_ns, lower_dentry, name, value, size, + flags); if (!rc && inode) fsstack_copy_attr_all(inode, d_inode(lower_dentry)); out: @@ -1089,7 +1090,7 @@ static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode, goto out; } inode_lock(lower_inode); - rc = __vfs_removexattr(lower_dentry, name); + rc = __vfs_removexattr(&init_user_ns, lower_dentry, name); inode_unlock(lower_inode); out: return rc; diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index 019572c6b39a..2f333a40ff4d 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -426,8 +426,8 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode) if (size < 0) size = 8; put_unaligned_be64(i_size_read(ecryptfs_inode), xattr_virt); - rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME, - xattr_virt, size, 0); + rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode, + ECRYPTFS_XATTR_NAME, xattr_virt, size, 0); inode_unlock(lower_inode); if (rc) printk(KERN_ERR "Error whilst attempting to write inode size " |