CVE-2024-35902

In the Linux kernel, the following vulnerability has been resolved:
net/rds: fix possible cp null dereference cp might be null, calling
cp->cp_conn would produce null dereference [Simon Horman adds:] Analysis: *
cp is a parameter of __rds_rdma_map and is not reassigned. * The following
call-sites pass a NULL cp argument to __rds_rdma_map() - rds_get_mr() -
rds_get_mr_for_dest * Prior to the code above, the following assumes that
cp may be NULL (which is indicative, but could itself be unnecessary)
trans_private = rs->rs_transport->get_mr( sg, nents, rs, &mr->r_key, cp ?
cp->cp_conn : NULL, args->vec.addr, args->vec.bytes, need_odp ?
ODP_ZEROBASED : ODP_NOT_NEEDED); * The code modified by this patch is
guarded by IS_ERR(trans_private), where trans_private is assigned as per
the previous point in this analysis. The only implementation of get_mr that
I could locate is rds_ib_get_mr() which can return an ERR_PTR if the conn
(4th) argument is NULL. * ret is set to PTR_ERR(trans_private).
rds_ib_get_mr can return ERR_PTR(-ENODEV) if the conn (4th) argument is
NULL. Thus ret may be -ENODEV in which case the code in question will
execute. Conclusion: * cp may be NULL at the point where this patch adds a
check; this patch does seem to address a possible bug