From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sun, 12 May 2019 21:23:30 +0000 (-0400)
Subject: legacy_get_tree(): pass fc->user_ns to mount_capable()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=fd912087f4a897cfdf8274f8085c501742638be2;p=linux.git

legacy_get_tree(): pass fc->user_ns to mount_capable()

guaranteed to be equal to current_user_ns() here - it has not
been changed since alloc_fs_context() (nothing in legacy
methods changes it) and since we don't have SB_SUBMOUNT,
that must've been FS_CONTEXT_FOR_MOUNT.  And in that case
we have fc->user_ns set to fc->cred->user_ns, i.e.
current_cred()->user_ns, i.e. current_user_ns()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/fs_context.c b/fs/fs_context.c
index 746a5871959cb..d75ba0eb8c5bc 100644
--- a/fs/fs_context.c
+++ b/fs/fs_context.c
@@ -663,7 +663,7 @@ static int legacy_get_tree(struct fs_context *fc)
 	struct dentry *root;
 
 	if (!(fc->sb_flags & (SB_KERNMOUNT|SB_SUBMOUNT))) {
-		if (!mount_capable(fc->fs_type, current_user_ns()))
+		if (!mount_capable(fc->fs_type, fc->user_ns))
 			return -EPERM;
 	}