linux/fs/ceph
Jan Kara 57c9cfdb61 posix_acl: Clear SGID bit when setting file permissions
commit 073931017b upstream.

When file permissions are modified via chmod(2) and the user is not in
the owning group or capable of CAP_FSETID, the setgid bit is cleared in
inode_change_ok().  Setting a POSIX ACL via setxattr(2) sets the file
permissions as well as the new ACL, but doesn't clear the setgid bit in
a similar way; this allows to bypass the check in chmod(2).  Fix that.

References: CVE-2016-7097
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31 04:13:58 -06:00
..
acl.c posix_acl: Clear SGID bit when setting file permissions 2016-10-31 04:13:58 -06:00
addr.c
cache.c
cache.h
caps.c
ceph_frag.c
debugfs.c
dir.c
export.c
file.c
inode.c
ioctl.c
ioctl.h
Kconfig
locks.c
Makefile
mds_client.c
mds_client.h
mdsmap.c
snap.c
strings.c
super.c
super.h
xattr.c