On Thu, Dec 23, 2021 at 10:57:33AM +0100, Christian Brauner wrote:
> From: Christian Brauner <christian.brauner@xxxxxxxxxx>
>
> Ceph always inherits the SGID bit if it is set on the parent inode,
> while the generic inode_init_owner does not do this in a few cases where
> it can create a possible security problem (cf. [1]).
>
> Update ceph to strip the SGID bit just as inode_init_owner would.
>
> This bug was detected by the mapped mount testsuite in [3]. The
> testsuite tests all core VFS functionality and semantics with and
> without mapped mounts. That is to say it functions as a generic VFS
> testsuite in addition to a mapped mount testsuite. While working on
> mapped mount support for ceph, SIGD inheritance was the only failing
> test for ceph after the port.
>
> The same bug was detected by the mapped mount testsuite in XFS in
> January 2021 (cf. [2]).
>
> [1]: commit 0fa3ecd87848 ("Fix up non-directory creation in SGID directories")
> [2]: commit 01ea173e103e ("xfs: fix up non-directory creation in SGID directories")
> [3]: https://git.kernel.org/fs/xfs/xfstests-dev.git
>
> Cc: stable@xxxxxxxxxxxxxxx (adapted to v5.10)
> Signed-off-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
> Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
> ---
> fs/ceph/file.c | 18 +++++++++++++++---
> 1 file changed, 15 insertions(+), 3 deletions(-)
What is the git commit id in Linus's tree?
