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4 commits

Author SHA1 Message Date
Stefano Garzarella
f6abafcd32 vsock/bpf: return early if transport is not assigned
Some of the core functions can only be called if the transport
has been assigned.

As Michal reported, a socket might have the transport at NULL,
for example after a failed connect(), causing the following trace:

    BUG: kernel NULL pointer dereference, address: 00000000000000a0
    #PF: supervisor read access in kernel mode
    #PF: error_code(0x0000) - not-present page
    PGD 12faf8067 P4D 12faf8067 PUD 113670067 PMD 0
    Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
    CPU: 15 UID: 0 PID: 1198 Comm: a.out Not tainted 6.13.0-rc2+
    RIP: 0010:vsock_connectible_has_data+0x1f/0x40
    Call Trace:
     vsock_bpf_recvmsg+0xca/0x5e0
     sock_recvmsg+0xb9/0xc0
     __sys_recvfrom+0xb3/0x130
     __x64_sys_recvfrom+0x20/0x30
     do_syscall_64+0x93/0x180
     entry_SYSCALL_64_after_hwframe+0x76/0x7e

So we need to check the `vsk->transport` in vsock_bpf_recvmsg(),
especially for connected sockets (stream/seqpacket) as we already
do in __vsock_connectible_recvmsg().

Fixes: 634f1a7110 ("vsock: support sockmap")
Cc: stable@vger.kernel.org
Reported-by: Michal Luczaj <mhal@rbox.co>
Closes: https://lore.kernel.org/netdev/5ca20d4c-1017-49c2-9516-f6f75fd331e9@rbox.co/
Tested-by: Michal Luczaj <mhal@rbox.co>
Reported-by: syzbot+3affdbfc986ecd9200fd@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/677f84a8.050a0220.25a300.01b3.GAE@google.com/
Tested-by: syzbot+3affdbfc986ecd9200fd@syzkaller.appspotmail.com
Reviewed-by: Hyunwoo Kim <v4bel@theori.io>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Luigi Leonardi <leonardi@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-01-14 12:29:37 +01:00
Michal Luczaj
19039f2797 bpf, vsock: Drop static vsock_bpf_prot initialization
vsock_bpf_prot is set up at runtime. Remove the superfluous init.

No functional change intended.

Fixes: 634f1a7110 ("vsock: support sockmap")
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20241013-vsock-fixes-for-redir-v2-4-d6577bbfe742@rbox.co
2024-10-17 13:02:55 +02:00
Cong Wang
69139d2919 vsock: fix recursive ->recvmsg calls
After a vsock socket has been added to a BPF sockmap, its prot->recvmsg
has been replaced with vsock_bpf_recvmsg(). Thus the following
recursiion could happen:

vsock_bpf_recvmsg()
 -> __vsock_recvmsg()
  -> vsock_connectible_recvmsg()
   -> prot->recvmsg()
    -> vsock_bpf_recvmsg() again

We need to fix it by calling the original ->recvmsg() without any BPF
sockmap logic in __vsock_recvmsg().

Fixes: 634f1a7110 ("vsock: support sockmap")
Reported-by: syzbot+bdb4bd87b5e22058e2a4@syzkaller.appspotmail.com
Tested-by: syzbot+bdb4bd87b5e22058e2a4@syzkaller.appspotmail.com
Cc: Bobby Eshleman <bobby.eshleman@bytedance.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://patch.msgid.link/20240812022153.86512-1-xiyou.wangcong@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-08-15 12:07:04 +02:00
Bobby Eshleman
634f1a7110 vsock: support sockmap
This patch adds sockmap support for vsock sockets. It is intended to be
usable by all transports, but only the virtio and loopback transports
are implemented.

SOCK_STREAM, SOCK_DGRAM, and SOCK_SEQPACKET are all supported.

Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-29 08:19:38 +01:00