From: hkbinbin <hkbinbinbin@gmail.com> mainline inclusion from mainline-v7.1-rc1 commit 7244491dab347f648e661da96dc0febadd9daec3 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/15307 CVE: CVE-2026-46043 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- 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. Cc: stable@vger.kernel.org Fixes: 8700e3e7c485 ("Soft RoCE driver") Link: https://patch.msgid.link/r/20260401121907.1468366-1-hkbinbinbin@gmail.com Signed-off-by: hkbinbin <hkbinbinbin@gmail.com> Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Liu Kai <liukai284@huawei.com> --- drivers/infiniband/sw/rxe/rxe_recv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/infiniband/sw/rxe/rxe_recv.c index cb69a125e280..71a56c4b721a 100644 --- a/drivers/infiniband/sw/rxe/rxe_recv.c +++ b/drivers/infiniband/sw/rxe/rxe_recv.c @@ -364,7 +364,8 @@ void rxe_rcv(struct sk_buff *skb) pkt->qp = NULL; pkt->mask |= rxe_opcode[pkt->opcode].mask; - if (unlikely(skb->len < header_size(pkt))) + if (unlikely(pkt->paylen < header_size(pkt) + bth_pad(pkt) + + RXE_ICRC_SIZE)) goto drop; err = hdr_check(pkt); -- 2.34.1