From: Michael S. Tsirkin Date: Mon, 22 Apr 2024 14:03:13 +0000 (-0400) Subject: vhost/vsock: always initialize seqpacket_allow X-Git-Tag: v6.11-rc1~110^2~55 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1e1fdcbdde3b7663e5d8faeb2245b9b151417d22;p=thirdparty%2Flinux.git vhost/vsock: always initialize seqpacket_allow There are two issues around seqpacket_allow: 1. seqpacket_allow is not initialized when socket is created. Thus if features are never set, it will be read uninitialized. 2. if VIRTIO_VSOCK_F_SEQPACKET is set and then cleared, then seqpacket_allow will not be cleared appropriately (existing apps I know about don't usually do this but it's legal and there's no way to be sure no one relies on this). To fix: - initialize seqpacket_allow after allocation - set it unconditionally in set_features Reported-by: syzbot+6c21aeb59d0e82eb2782@syzkaller.appspotmail.com Reported-by: Jeongjun Park Fixes: ced7b713711f ("vhost/vsock: support SEQPACKET for transport"). Tested-by: Arseny Krasnov Cc: David S. Miller Cc: Stefan Hajnoczi Message-ID: <20240422100010-mutt-send-email-mst@kernel.org> Signed-off-by: Michael S. Tsirkin Acked-by: Jason Wang Reviewed-by: Stefano Garzarella Reviewed-by: Eugenio Pérez Acked-by: Jakub Kicinski --- diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c index ec20ecff85c7f..bf664ec9341b3 100644 --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -667,6 +667,7 @@ static int vhost_vsock_dev_open(struct inode *inode, struct file *file) } vsock->guest_cid = 0; /* no CID assigned yet */ + vsock->seqpacket_allow = false; atomic_set(&vsock->queued_replies, 0); @@ -810,8 +811,7 @@ static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features) goto err; } - if (features & (1ULL << VIRTIO_VSOCK_F_SEQPACKET)) - vsock->seqpacket_allow = true; + vsock->seqpacket_allow = features & (1ULL << VIRTIO_VSOCK_F_SEQPACKET); for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { vq = &vsock->vqs[i];