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| author | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-21 14:19:24 +0100 |
|---|---|---|
| committer | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-24 14:27:16 +0100 |
| commit | 47291baa8ddfdae10663624ff0a15ab165952708 (patch) | |
| tree | 132a9486b82c5eada1c4b375f693522f0a04d629 /fs/btrfs/ioctl.c | |
| parent | 0558c1bf5a0811bf5e3753eed911a15b9bd08271 (diff) | |
| download | linux-stable-47291baa8ddfdae10663624ff0a15ab165952708.tar.gz linux-stable-47291baa8ddfdae10663624ff0a15ab165952708.tar.bz2 linux-stable-47291baa8ddfdae10663624ff0a15ab165952708.zip | |
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: https://lore.kernel.org/r/20210121131959.646623-6-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>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Diffstat (limited to 'fs/btrfs/ioctl.c')
| -rw-r--r-- | fs/btrfs/ioctl.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index dde49a791f3e..8ced6dfefee4 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -922,7 +922,7 @@ static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir) BUG_ON(d_inode(victim->d_parent) != dir); audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); - error = inode_permission(dir, MAY_WRITE | MAY_EXEC); + error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC); if (error) return error; if (IS_APPEND(dir)) @@ -951,7 +951,7 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child) return -EEXIST; if (IS_DEADDIR(dir)) return -ENOENT; - return inode_permission(dir, MAY_WRITE | MAY_EXEC); + return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC); } /* @@ -2538,7 +2538,8 @@ static int btrfs_search_path_in_tree_user(struct inode *inode, ret = PTR_ERR(temp_inode); goto out_put; } - ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC); + ret = inode_permission(&init_user_ns, temp_inode, + MAY_READ | MAY_EXEC); iput(temp_inode); if (ret) { ret = -EACCES; @@ -3068,7 +3069,8 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file, if (root == dest) goto out_dput; - err = inode_permission(inode, MAY_WRITE | MAY_EXEC); + err = inode_permission(&init_user_ns, inode, + MAY_WRITE | MAY_EXEC); if (err) goto out_dput; } @@ -3139,7 +3141,7 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp) * running and allows defrag on files open in read-only mode. */ if (!capable(CAP_SYS_ADMIN) && - inode_permission(inode, MAY_WRITE)) { + inode_permission(&init_user_ns, inode, MAY_WRITE)) { ret = -EPERM; goto out; } |