summaryrefslogtreecommitdiffhomepage
path: root/pkg/sentry/syscalls/linux
diff options
context:
space:
mode:
Diffstat (limited to 'pkg/sentry/syscalls/linux')
-rw-r--r--pkg/sentry/syscalls/linux/sys_socket.go13
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/socket.go13
2 files changed, 20 insertions, 6 deletions
diff --git a/pkg/sentry/syscalls/linux/sys_socket.go b/pkg/sentry/syscalls/linux/sys_socket.go
index eff251cec..5e9e940df 100644
--- a/pkg/sentry/syscalls/linux/sys_socket.go
+++ b/pkg/sentry/syscalls/linux/sys_socket.go
@@ -383,12 +383,19 @@ func Listen(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal
// Linux treats incoming backlog as uint with a limit defined by
// sysctl_somaxconn.
// https://github.com/torvalds/linux/blob/7acac4b3196/net/socket.c#L1666
- //
- // We use the backlog to allocate a channel of that size, hence enforce
- // a hard limit for the backlog.
backlog = maxListenBacklog
}
+ // Accept one more than the configured listen backlog to keep in parity with
+ // Linux. Ref, because of missing equality check here:
+ // https://github.com/torvalds/linux/blob/7acac4b3196/include/net/sock.h#L937
+ //
+ // In case of unix domain sockets, the following check
+ // https://github.com/torvalds/linux/blob/7d6beb71da3/net/unix/af_unix.c#L1293
+ // will allow 1 connect through since it checks for a receive queue len >
+ // backlog and not >=.
+ backlog++
+
return 0, nil, s.Listen(t, int(backlog)).ToError()
}
diff --git a/pkg/sentry/syscalls/linux/vfs2/socket.go b/pkg/sentry/syscalls/linux/vfs2/socket.go
index 936614eab..6edde0ed1 100644
--- a/pkg/sentry/syscalls/linux/vfs2/socket.go
+++ b/pkg/sentry/syscalls/linux/vfs2/socket.go
@@ -387,12 +387,19 @@ func Listen(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal
// Linux treats incoming backlog as uint with a limit defined by
// sysctl_somaxconn.
// https://github.com/torvalds/linux/blob/7acac4b3196/net/socket.c#L1666
- //
- // We use the backlog to allocate a channel of that size, hence enforce
- // a hard limit for the backlog.
backlog = maxListenBacklog
}
+ // Accept one more than the configured listen backlog to keep in parity with
+ // Linux. Ref, because of missing equality check here:
+ // https://github.com/torvalds/linux/blob/7acac4b3196/include/net/sock.h#L937
+ //
+ // In case of unix domain sockets, the following check
+ // https://github.com/torvalds/linux/blob/7d6beb71da3/net/unix/af_unix.c#L1293
+ // will allow 1 connect through since it checks for a receive queue len >
+ // backlog and not >=.
+ backlog++
+
return 0, nil, s.Listen(t, int(backlog)).ToError()
}