Vulnerability CVE-2024-42145
Published: 2024-07-30

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

IB/core: Implement a limit on UMAD receive List

The existing behavior of ib_umad, which maintains received MAD
packets in an unbounded list, poses a risk of uncontrolled growth.
As user-space applications extract packets from this list, the rate
of extraction may not match the rate of incoming packets, leading
to potential list overflow.

To address this, we introduce a limit to the size of the list. After
considering typical scenarios, such as OpenSM processing, which can
handle approximately 100k packets per second, and the 1-second retry
timeout for most packets, we set the list size limit to 200k. Packets
received beyond this limit are dropped, assuming they are likely timed
out by the time they are handled by user-space.

Notably, packets queued on the receive list due to reasons like
timed-out sends are preserved even when the list is full.

 References:
https://git.kernel.org/stable/c/1288cf1cceb0e6df276e182f5412370fb4169bcb
https://git.kernel.org/stable/c/b4913702419d064ec4c4bbf7270643c95cc89a1b
https://git.kernel.org/stable/c/62349fbf86b5e13b02721bdadf98c29afd1e7b5f
https://git.kernel.org/stable/c/d73cb8862e4d6760ccc94d3b57b9ef6271400607
https://git.kernel.org/stable/c/63d202d948bb6d3a28cd8e8b96b160fa53e18baa
https://git.kernel.org/stable/c/b8c5f635997f49c625178d1a0cb32a80ed33abe6
https://git.kernel.org/stable/c/a6627fba793cc75b7365d9504a0095fb2902dda4
https://git.kernel.org/stable/c/ca0b44e20a6f3032224599f02e7c8fb49525c894
Copyright 2026, cxsecurity.com

 

Back to Top