path: root/fs/open.c
diff options
authorChristian Brauner <>2021-01-21 14:19:24 +0100
committerChristian Brauner <>2021-01-24 14:27:16 +0100
commit47291baa8ddfdae10663624ff0a15ab165952708 (patch)
tree132a9486b82c5eada1c4b375f693522f0a04d629 /fs/open.c
parent0558c1bf5a0811bf5e3753eed911a15b9bd08271 (diff)
namei: make permission helpers idmapped mount aware
The two helpers inode_permission() and generic_permission() are used by the vfs to perform basic permission checking by verifying that the caller is privileged over an inode. In order to handle idmapped mounts we extend the two helpers with an additional user namespace argument. On idmapped mounts the two helpers will make sure to map the inode according to the mount's user namespace and then peform identical permission checks to inode_permission() and generic_permission(). If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: Cc: Christoph Hellwig <> Cc: David Howells <> Cc: Al Viro <> Cc: Reviewed-by: Christoph Hellwig <> Reviewed-by: James Morris <> Acked-by: Serge Hallyn <> Signed-off-by: Christian Brauner <>
Diffstat (limited to 'fs/open.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/open.c b/fs/open.c
index cd1efd254cad..a6dac6d97988 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -83,7 +83,7 @@ long vfs_truncate(const struct path *path, loff_t length)
if (error)
goto out;
- error = inode_permission(inode, MAY_WRITE);
+ error = inode_permission(&init_user_ns, inode, MAY_WRITE);
if (error)
goto mnt_drop_write_and_out;
@@ -436,7 +436,7 @@ retry:
goto out_path_release;
- res = inode_permission(inode, mode | MAY_ACCESS);
+ res = inode_permission(&init_user_ns, inode, mode | MAY_ACCESS);
/* SuS v2 requires we report a read only fs too */
if (res || !(mode & S_IWOTH) || special_file(inode->i_mode))
goto out_path_release;