CVE-2026-90149

Status: UPDATED  |  Advisory ID: CVE-2026-90149

Key Details

Affected Products, Subsystems & Sectors

What to Know

In the Linux kernel, the following vulnerability has been resolved:

NFSv4/flexfiles: fix NULL dereference for NFSv4.0 data servers

flexfiles accepts NFSv4.0 data servers, but two NFSv4 code paths assume

the data server client has a session. Unlike NFSv4.1+, an NFSv4.0 client

has no session (clp->cl_session is NULL; it uses clp->cl_slot_tbl), so

I/O to a v4.0 flexfiles DS oopses:

- nfs4_init_ds_session() dereferences clp->cl_session->session_state

while seeding the DS lease. It also only seeds cl_lease_time when

NFS4_SESSION_INITING is set; without a session that never happens, so

cl_lease_time stays 0 and nfs4_renew_state() busy-loops, requeuing

every 5 seconds. Seed the lease whenever there is no session and

return before touching session state.

- ff_layout_async_handle_error_v4() dereferences

clp->cl_session->fc_slot_table on every DS I/O error. Fall back to the

v4.0 transport slot table (clp->cl_slot_tbl) when there is no session. (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References