diff options
Diffstat (limited to 'pkg/sentry/syscalls/linux')
-rw-r--r-- | pkg/sentry/syscalls/linux/sys_socket.go | 13 | ||||
-rw-r--r-- | pkg/sentry/syscalls/linux/vfs2/socket.go | 13 |
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() } |