CVE-2026-46043RDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv

Official description

In the Linux kernel, the following vulnerability has been resolved: RDMA/rxe: Validate pad and ICRC before payload_size() in rxe_rcv rxe_rcv() currently checks only that the incoming packet is at least header_size(pkt) bytes long before payload_size() is used. However, payload_size() subtracts both the attacker-controlled BTH pad field and RXE_ICRC_SIZE from pkt->paylen: payload_size = pkt->paylen - offset[RXE_PAYLOAD] - bth_pad(pkt) - RXE_ICRC_SIZE This means a short packet can still make payload_size() underflow even if it includes enough bytes for the fixed headers. Simply requiring header_size(pkt) + RXE_ICRC_SIZE is not sufficient either, because a packet with a forged non-zero BTH pad can still leave payload_size() negative and pass an underflowed value to later receive-path users. Fix this by validating pkt->paylen against the full minimum length required by payload_size(): header_size(pkt) + bth_pad(pkt) + RXE_ICRC_SIZE.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/c4376c672c3648d5bdc31dfffc329d07164f93c4
• https://git.kernel.org/stable/c/5fedefec757192dcaad29a664ac332c7601be144
• https://git.kernel.org/stable/c/2c0d71ef12f46c57d37bc571f3f2797db7eb50cc
• https://git.kernel.org/stable/c/2fd4f8b749309a61c3f3f88ee8891d94f79e1240
• https://git.kernel.org/stable/c/f83519a4c122c9c7a850a2197648a9ff4c67c520
• https://git.kernel.org/stable/c/9b924f3a26b21330a837cfe72e819b6393bbeeaa
• https://git.kernel.org/stable/c/e8ee0e792d475b1067c199ef0af1b6221fa6f43d
• https://git.kernel.org/stable/c/7244491dab347f648e661da96dc0febadd9daec3