Stefano Garzarella c6087c5aaa vsock/virtio: fix skb overhead accounting to preserve full buf_alloc ... After commit 059b7dbd20 ("vsock/virtio: fix potential unbounded skb queue"), virtio_transport_inc_rx_pkt() subtracts per-skb overhead from buf_alloc when checking whether a new packet fits. This reduces the effective receive buffer below what the user configured via SO_VM_SOCKETS_BUFFER_SIZE, causing legitimate data packets to be silently dropped and applications that rely on the full buffer size to deadlock. Also, the reduced space is not communicated to the remote peer, so its credit calculation accounts more credit than the receiver will actually accept, causing data loss (there is no retransmission). With this approach we currently have failures in tools/testing/vsock/vsock_test.c. Test 18 sometimes fails, while test 22 always fails in this way: 18 - SOCK_STREAM MSG_ZEROCOPY...hash mismatch 22 - SOCK_STREAM virtio credit update + SO_RCVLOWAT...send failed: Resource temporarily unavailable Fix by allowing at most `buf_alloc * 2` as the total budget for payload plus skb overhead in virtio_transport_inc_rx_pkt(), similar to how SO_RCVBUF is doubled to reserve space for sk_buff metadata. This preserves the full buf_alloc for payload under normal operation, while still bounding the skb queue growth. With this patch, all tests in tools/testing/vsock/vsock_test.c are now passing again. Fixes: 059b7dbd20 ("vsock/virtio: fix potential unbounded skb queue") Cc: stable@vger.kernel.org Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://patch.msgid.link/20260518090656.134588-3-sgarzare@redhat.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>		2026-05-21 13:14:01 +02:00
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Kconfig	Drivers: hv: Add CONFIG_HYPERV_VMBUS option	2025-10-01 00:00:42 +00:00
Makefile	vsock: support sockmap	2023-03-29 08:19:38 +01:00
af_vsock.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2026-04-14 12:04:00 -07:00
af_vsock_tap.c	…
diag.c	sock_diag: add module pointer to "struct sock_diag_handler"	2024-01-23 15:13:54 +01:00
hyperv_transport.c	hv_sock: fix ARM64 support	2026-04-29 17:30:45 -07:00
virtio_transport.c	vsock: add G2H fallback for CIDs not owned by H2G transport	2026-03-12 10:59:36 +01:00
virtio_transport_common.c	vsock/virtio: fix skb overhead accounting to preserve full buf_alloc	2026-05-21 13:14:01 +02:00
vmci_transport.c	vsock/vmci: fix UAF when peer resets connection during handshake	2026-05-20 19:11:18 -07:00
vmci_transport.h	vsock: Remove unused function declarations	2023-07-31 14:41:08 -07:00
vmci_transport_notify.c	vmci/vsock: check SO_RCVLOWAT before wake up reader	2022-08-23 10:43:12 +02:00
vmci_transport_notify.h	…
vmci_transport_notify_qstate.c	vmci/vsock: check SO_RCVLOWAT before wake up reader	2022-08-23 10:43:12 +02:00
vsock_addr.c	net: Convert proto_ops connect() callbacks to use sockaddr_unsized	2025-11-04 19:10:32 -08:00
vsock_bpf.c	net: remove addr_len argument of recvmsg() handlers	2026-03-02 18:17:17 -08:00
vsock_loopback.c	vsock: add netns support to virtio transports	2026-01-27 10:45:38 +01:00