CVE-2026-45889
published 2026-05-27CVE-2026-45889: In the Linux kernel, the following vulnerability has been resolved: mptcp: do not account for OoO in mptcp_rcvbuf_grow() MPTCP-level OoOs are physiological…
In the Linux kernel, the following vulnerability has been resolved:
mptcp: do not account for OoO in mptcp_rcvbuf_grow()
MPTCP-level OoOs are physiological when multiple subflows are active
concurrently and will not cause retransmissions nor are caused by
drops.
Accounting for them in mptcp_rcvbuf_grow() causes the rcvbuf slowly
drifting towards tcp_rmem[2].
Remove such accounting. Note that subflows will still account for TCP-level
OoO when the MPTCP-level rcvbuf is propagated.
This also closes a subtle and very unlikely race condition with rcvspace
init; active sockets with user-space holding the msk-level socket lock,
could complete such initialization in the receive callback, after that the
first OoO data reaches the rcvbuf and potentially triggering a divide by
zero Oops.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= e118cdc34dd109562b64f6a397f68cd33b041d5b < fb7bf00b04a6b48859f52035d4e745848c2b4c79 | fb7bf00b04a6b48859f52035d4e745848c2b4c79 |
| linux | linux | >= e118cdc34dd109562b64f6a397f68cd33b041d5b < 400ee4854adef1e4983812a3decf6717ea020136 | 400ee4854adef1e4983812a3decf6717ea020136 |
| linux | linux | >= e118cdc34dd109562b64f6a397f68cd33b041d5b < 6b329393502e5857662b851a13f947209c588587 | 6b329393502e5857662b851a13f947209c588587 |
| linux | linux_kernel | — | — |