Re: [PATCH v1 2/2] io_uring,audit: do not log IORING_OP_*GETXATTR
On Friday, January 27, 2023 5:43:02 PM EST Paul Moore wrote:
On Fri, Jan 27, 2023 at 12:24 PM Richard Guy Briggs
<rgb(a)redhat.com> wrote:
> Getting XATTRs is not particularly interesting security-wise.
>
> Suggested-by: Steve Grubb <sgrubb(a)redhat.com>
> Fixes: a56834e0fafe ("io_uring: add fgetxattr and getxattr support")
> Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com>
> ---
> io_uring/opdef.c | 2 ++
> 1 file changed, 2 insertions(+)
Depending on your security policy, fetching file data, including
xattrs, can be interesting from a security perspective. As an
example, look at the SELinux file/getattr permission.
https://github.com/SELinuxProject/selinux-notebook/blob/main/src/object_cla
sses_permissions.md#common-file-permissions
We're mostly interested in setting attributes because that changes policy.
Reading them is not interesting unless the access fails with EPERM.
I was updating the user space piece recently and saw there was a bunch of
"new" operations. I was commenting that we need to audit 5 or 6 of the
"new"
operations such as IORING_OP_MKDIRATor IORING_OP_SETXATTR. But now that I see
the patch, it looks like they are auditable and we can just let a couple be
skipped. IORING_OP_MADVISE is not interesting as it just gives hiints about
the expected access patterns of memory. If there were an equivalent of
mprotect, that would be of interest, but not madvise.
There are some I'm not sure about such as IORING_OP_MSG_RING and
IORING_OP_URING_CMD. What do they do?
-Steve