kernel/git/stable/linux.git/net/vmw_vsock, branch linux-6.15.y

vsock/virtio: Resize receive buffers so that each SKB fits in a 4K page

2025-08-20T16:36:15+00:00

[ Upstream commit 03a92f036a04fed2b00d69f5f46f1a486e70dc5c ] When allocating receive buffers for the vsock virtio RX virtqueue, an SKB is allocated with a 4140 data payload (the 44-byte packet header + VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE). Even when factoring in the SKB overhead, the resulting 8KiB allocation thanks to the rounding in kmalloc_reserve() is wasteful (~3700 unusable bytes) and results in a higher-order page allocation on systems with 4KiB pages just for the sake of a few hundred bytes of packet data. Limit the vsock virtio RX buffers to 4KiB per SKB, resulting in much better memory utilisation and removing the need to allocate higher-order pages entirely. Reviewed-by: Stefano Garzarella Signed-off-by: Will Deacon Message-Id: <20250717090116.11987-5-will@kernel.org> Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin

vsock: Do not allow binding to VMADDR_PORT_ANY

2025-08-15T10:17:04+00:00

commit aba0c94f61ec05315fa7815d21aefa4c87f6a9f4 upstream. It is possible for a vsock to autobind to VMADDR_PORT_ANY. This can cause a use-after-free when a connection is made to the bound socket. The socket returned by accept() also has port VMADDR_PORT_ANY but is not on the list of unbound sockets. Binding it will result in an extra refcount decrement similar to the one fixed in fcdd2242c023 (vsock: Keep the binding until socket destruction). Modify the check in __vsock_bind_connectible() to also prevent binding to VMADDR_PORT_ANY. Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Reported-by: Budimir Markovic Signed-off-by: Budimir Markovic Reviewed-by: Stefano Garzarella Link: https://patch.msgid.link/20250807041811.678-1-markovicbudimir@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

vsock: Fix IOCTL_VM_SOCKETS_GET_LOCAL_CID to check also `transport_local`

2025-07-17T16:43:41+00:00

[ Upstream commit 1e7d9df379a04ccd0c2f82f39fbb69d482e864cc ] Support returning VMADDR_CID_LOCAL in case no other vsock transport is available. Fixes: 0e12190578d0 ("vsock: add local transport support in the vsock core") Suggested-by: Stefano Garzarella Reviewed-by: Stefano Garzarella Signed-off-by: Michal Luczaj Link: https://patch.msgid.link/20250703-vsock-transports-toctou-v4-3-98f0eb530747@rbox.co Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

vsock: Fix transport_* TOCTOU

2025-07-17T16:43:41+00:00

[ Upstream commit 687aa0c5581b8d4aa87fd92973e4ee576b550cdf ] Transport assignment may race with module unload. Protect new_transport from becoming a stale pointer. This also takes care of an insecure call in vsock_use_local_transport(); add a lockdep assert. BUG: unable to handle page fault for address: fffffbfff8056000 Oops: Oops: 0000 [#1] SMP KASAN RIP: 0010:vsock_assign_transport+0x366/0x600 Call Trace: vsock_connect+0x59c/0xc40 __sys_connect+0xe8/0x100 __x64_sys_connect+0x6e/0xc0 do_syscall_64+0x92/0x1c0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") Reviewed-by: Stefano Garzarella Signed-off-by: Michal Luczaj Link: https://patch.msgid.link/20250703-vsock-transports-toctou-v4-2-98f0eb530747@rbox.co Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

vsock: Fix transport_{g2h,h2g} TOCTOU

2025-07-17T16:43:41+00:00

[ Upstream commit 209fd720838aaf1420416494c5505096478156b4 ] vsock_find_cid() and vsock_dev_do_ioctl() may race with module unload. transport_{g2h,h2g} may become NULL after the NULL check. Introduce vsock_transport_local_cid() to protect from a potential null-ptr-deref. KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f] RIP: 0010:vsock_find_cid+0x47/0x90 Call Trace: __vsock_bind+0x4b2/0x720 vsock_bind+0x90/0xe0 __sys_bind+0x14d/0x1e0 __x64_sys_bind+0x6e/0xc0 do_syscall_64+0x92/0x1c0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 KASAN: null-ptr-deref in range [0x0000000000000118-0x000000000000011f] RIP: 0010:vsock_dev_do_ioctl.isra.0+0x58/0xf0 Call Trace: __x64_sys_ioctl+0x12d/0x190 do_syscall_64+0x92/0x1c0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") Suggested-by: Stefano Garzarella Reviewed-by: Stefano Garzarella Signed-off-by: Michal Luczaj Link: https://patch.msgid.link/20250703-vsock-transports-toctou-v4-1-98f0eb530747@rbox.co Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

vsock/vmci: Clear the vmci transport packet properly when initializing it

2025-07-10T14:08:23+00:00

commit 223e2288f4b8c262a864e2c03964ffac91744cd5 upstream. In vmci_transport_packet_init memset the vmci_transport_packet before populating the fields to avoid any uninitialised data being left in the structure. Cc: Bryan Tan Cc: Vishnu Dasa Cc: Broadcom internal kernel review list Cc: Stefano Garzarella Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Simon Horman Cc: virtualization@lists.linux.dev Cc: netdev@vger.kernel.org Cc: stable Signed-off-by: HarshaVardhana S A Signed-off-by: Greg Kroah-Hartman Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Acked-by: Stefano Garzarella Link: https://patch.msgid.link/20250701122254.2397440-1-gregkh@linuxfoundation.org Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman

vsock/virtio: fix `rx_bytes` accounting for stream sockets

2025-06-19T13:40:00+00:00

[ Upstream commit 45ca7e9f0730ae36fc610e675b990e9cc9ca0714 ] In `struct virtio_vsock_sock`, we maintain two counters: - `rx_bytes`: used internally to track how many bytes have been read. This supports mechanisms like .stream_has_data() and sock_rcvlowat(). - `fwd_cnt`: used for the credit mechanism to inform available receive buffer space to the remote peer. These counters are updated via virtio_transport_inc_rx_pkt() and virtio_transport_dec_rx_pkt(). Since the beginning with commit 06a8fc78367d ("VSOCK: Introduce virtio_vsock_common.ko"), we call virtio_transport_dec_rx_pkt() in virtio_transport_stream_do_dequeue() only when we consume the entire packet, so partial reads, do not update `rx_bytes` and `fwd_cnt`. This is fine for `fwd_cnt`, because we still have space used for the entire packet, and we don't want to update the credit for the other peer until we free the space of the entire packet. However, this causes `rx_bytes` to be stale on partial reads. Previously, this didn’t cause issues because `rx_bytes` was used only by .stream_has_data(), and any unread portion of a packet implied data was still available. However, since commit 93b808876682 ("virtio/vsock: fix logic which reduces credit update messages"), we now rely on `rx_bytes` to determine if a credit update should be sent when the data in the RX queue drops below SO_RCVLOWAT value. This patch fixes the accounting by updating `rx_bytes` with the number of bytes actually read, even on partial reads, while leaving `fwd_cnt` untouched until the packet is fully consumed. Also introduce a new `buf_used` counter to check that the remote peer is honoring the given credit; this was previously done via `rx_bytes`. Fixes: 93b808876682 ("virtio/vsock: fix logic which reduces credit update messages") Signed-off-by: Stefano Garzarella Link: https://patch.msgid.link/20250521121705.196379-1-sgarzare@redhat.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

vsock: avoid timeout during connect() if the socket is closing

2025-04-03T00:19:30+00:00

When a peer attempts to establish a connection, vsock_connect() contains a loop that waits for the state to be TCP_ESTABLISHED. However, the other peer can be fast enough to accept the connection and close it immediately, thus moving the state to TCP_CLOSING. When this happens, the peer in the vsock_connect() is properly woken up, but since the state is not TCP_ESTABLISHED, it goes back to sleep until the timeout expires, returning -ETIMEDOUT. If the socket state is TCP_CLOSING, waiting for the timeout is pointless. vsock_connect() can return immediately without errors or delay since the connection actually happened. The socket will be in a closing state, but this is not an issue, and subsequent calls will fail as expected. We discovered this issue while developing a test that accepts and immediately closes connections to stress the transport switch between two connect() calls, where the first one was interrupted by a signal (see Closes link). Reported-by: Luigi Leonardi Closes: https://lore.kernel.org/virtualization/bq6hxrolno2vmtqwcvb5bljfpb7mvwb3kohrvaed6auz5vxrfv@ijmd2f3grobn/ Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Signed-off-by: Stefano Garzarella Acked-by: Paolo Abeni Tested-by: Luigi Leonardi Reviewed-by: Luigi Leonardi Link: https://patch.msgid.link/20250328141528.420719-1-sgarzare@redhat.com Signed-off-by: Jakub Kicinski

vsock/bpf: Warn on socket without transport

2025-02-18T11:00:01+00:00

In the spirit of commit 91751e248256 ("vsock: prevent null-ptr-deref in vsock_*[has_data|has_space]"), armorize the "impossible" cases with a warning. Fixes: 634f1a7110b4 ("vsock: support sockmap") Signed-off-by: Michal Luczaj Reviewed-by: Stefano Garzarella Signed-off-by: Paolo Abeni

vsock/virtio: fix variables initialization during resuming

2025-02-15T03:52:06+00:00

When executing suspend to ram twice in a row, the `rx_buf_nr` and `rx_buf_max_nr` increase to three times vq->num_free. Then after virtqueue_get_buf and `rx_buf_nr` decreased in function virtio_transport_rx_work, the condition to fill rx buffer (rx_buf_nr < rx_buf_max_nr / 2) will never be met. It is because that `rx_buf_nr` and `rx_buf_max_nr` are initialized only in virtio_vsock_probe(), but they should be reset whenever virtqueues are recreated, like after a suspend/resume. Move the `rx_buf_nr` and `rx_buf_max_nr` initialization in virtio_vsock_vqs_init(), so we are sure that they are properly initialized, every time we initialize the virtqueues, either when we load the driver or after a suspend/resume. To prevent erroneous atomic load operations on the `queued_replies` in the virtio_transport_send_pkt_work() function which may disrupt the scheduling of vsock->rx_work when transmitting reply-required socket packets, this atomic variable must undergo synchronized initialization alongside the preceding two variables after a suspend/resume. Fixes: bd50c5dc182b ("vsock/virtio: add support for device suspend/resume") Link: https://lore.kernel.org/virtualization/20250207052033.2222629-1-junnan01.wu@samsung.com/ Co-developed-by: Ying Gao Signed-off-by: Ying Gao Signed-off-by: Junnan Wu Reviewed-by: Luigi Leonardi Acked-by: Michael S. Tsirkin Reviewed-by: Stefano Garzarella Link: https://patch.msgid.link/20250214012200.1883896-1-junnan01.wu@samsung.com Signed-off-by: Jakub Kicinski