This is a note to let you know that I've just added the patch titled
ovl: remove privs in ovl_fallocate()
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_fallocate.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 23a8ce16419a3066829ad4a8b7032a75817af65b Mon Sep 17 00:00:00 2001
From: Amir Goldstein <amir73il@xxxxxxxxx>
Date: Mon, 17 Oct 2022 17:06:39 +0200
Subject: ovl: remove privs in ovl_fallocate()
From: Amir Goldstein <amir73il@xxxxxxxxx>
commit 23a8ce16419a3066829ad4a8b7032a75817af65b upstream.
Underlying fs doesn't remove privs because fallocate is called with
privileged mounter credentials.
This fixes some failure in fstests generic/683..687.
Fixes: aab8848cee5e ("ovl: add ovl_fallocate()")
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 | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -531,9 +531,16 @@ static long ovl_fallocate(struct file *f
const struct cred *old_cred;
int ret;
+ inode_lock(inode);
+ /* Update mode */
+ ovl_copyattr(ovl_inode_real(inode), inode);
+ ret = file_remove_privs(file);
+ if (ret)
+ goto out_unlock;
+
ret = ovl_real_fdget(file, &real);
if (ret)
- return ret;
+ goto out_unlock;
old_cred = ovl_override_creds(file_inode(file)->i_sb);
ret = vfs_fallocate(real.file, mode, offset, len);
@@ -544,6 +551,9 @@ static long ovl_fallocate(struct file *f
fdput(real);
+out_unlock:
+ inode_unlock(inode);
+
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
