fs: make helpers idmap mount aware
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.
As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.
Link: https://lore.kernel.org/r/20210121131959.646623-25-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>
diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index 05b1f51..1576ff3 100644
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -152,7 +152,8 @@ static void bpf_dentry_finalize(struct dentry *dentry, struct inode *inode,
dir->i_ctime = dir->i_mtime;
}
-static int bpf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int bpf_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, umode_t mode)
{
struct inode *inode;
@@ -381,8 +382,8 @@ bpf_lookup(struct inode *dir, struct dentry *dentry, unsigned flags)
return simple_lookup(dir, dentry, flags);
}
-static int bpf_symlink(struct inode *dir, struct dentry *dentry,
- const char *target)
+static int bpf_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, const char *target)
{
char *link = kstrdup(target, GFP_USER | __GFP_NOWARN);
struct inode *inode;