This is a note to let you know that I've just added the patch titled
ovl: remove privs in ovl_copyfile()
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ovl-remove-privs-in-ovl_copyfile.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From b306e90ffabdaa7e3b3350dbcd19b7663e71ab17 Mon Sep 17 00:00:00 2001
From: Amir Goldstein <amir73il@xxxxxxxxx>
Date: Mon, 17 Oct 2022 17:06:38 +0200
Subject: ovl: remove privs in ovl_copyfile()
From: Amir Goldstein <amir73il@xxxxxxxxx>
commit b306e90ffabdaa7e3b3350dbcd19b7663e71ab17 upstream.
Underlying fs doesn't remove privs because copy_range/remap_range are
called with privileged mounter credentials.
This fixes some failures in fstest generic/673.
Fixes: 8ede205541ff ("ovl: add reflink/copyfile/dedup support")
Acked-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
Signed-off-by: Christian Brauner (Microsoft) <brauner@xxxxxxxxxx>
Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/overlayfs/file.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -687,14 +687,23 @@ static loff_t ovl_copyfile(struct file *
const struct cred *old_cred;
loff_t ret;
+ inode_lock(inode_out);
+ if (op != OVL_DEDUPE) {
+ /* Update mode */
+ ovl_copyattr(ovl_inode_real(inode_out), inode_out);
+ ret = file_remove_privs(file_out);
+ if (ret)
+ goto out_unlock;
+ }
+
ret = ovl_real_fdget(file_out, &real_out);
if (ret)
- return ret;
+ goto out_unlock;
ret = ovl_real_fdget(file_in, &real_in);
if (ret) {
fdput(real_out);
- return ret;
+ goto out_unlock;
}
old_cred = ovl_override_creds(file_inode(file_out)->i_sb);
@@ -723,6 +732,9 @@ static loff_t ovl_copyfile(struct file *
fdput(real_in);
fdput(real_out);
+out_unlock:
+ inode_unlock(inode_out);
+
return ret;
}
Patches currently in stable-queue which might be from amir73il@xxxxxxxxx are
queue-5.10/ovl-remove-privs-in-ovl_fallocate.patch
queue-5.10/ovl-remove-privs-in-ovl_copyfile.patch
