commands: handle epipe

If we start a lxc_wait on a container while it is exiting, it is
possible that we open the command socket, then the command socket
monitor closes all its mainloop sockets and exit, then we send our
credentials. Then we get killed by SIGPIPE.

Handle that case, recognizing that if we get sigpipe then the
container is (now) stopped.

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
This commit is contained in:
Serge Hallyn 2014-03-25 15:50:06 -05:00 committed by Stéphane Graber
parent 70084daff6
commit 6168ff15aa
2 changed files with 12 additions and 3 deletions

View File

@ -158,7 +158,7 @@ int lxc_abstract_unix_send_fd(int fd, int sendfd, void *data, size_t size)
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
return sendmsg(fd, &msg, 0);
return sendmsg(fd, &msg, MSG_NOSIGNAL);
}
int lxc_abstract_unix_recv_fd(int fd, int *recvfd, void *data, size_t size)
@ -230,7 +230,7 @@ int lxc_abstract_unix_send_credential(int fd, void *data, size_t size)
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
return sendmsg(fd, &msg, 0);
return sendmsg(fd, &msg, MSG_NOSIGNAL);
}
int lxc_abstract_unix_rcv_credential(int fd, void *data, size_t size)

View File

@ -263,6 +263,8 @@ static int lxc_cmd(const char *name, struct lxc_cmd_rr *cmd, int *stopped,
ret = lxc_abstract_unix_send_credential(sock, &cmd->req, sizeof(cmd->req));
if (ret != sizeof(cmd->req)) {
if (errno == EPIPE)
goto epipe;
SYSERROR("command %s failed to send req to '@%s' %d",
lxc_cmd_str(cmd->req.cmd), offset, ret);
if (ret >=0)
@ -271,8 +273,10 @@ static int lxc_cmd(const char *name, struct lxc_cmd_rr *cmd, int *stopped,
}
if (cmd->req.datalen > 0) {
ret = send(sock, cmd->req.data, cmd->req.datalen, 0);
ret = send(sock, cmd->req.data, cmd->req.datalen, MSG_NOSIGNAL);
if (ret != cmd->req.datalen) {
if (errno == EPIPE)
goto epipe;
SYSERROR("command %s failed to send request data to '@%s' %d",
lxc_cmd_str(cmd->req.cmd), offset, ret);
if (ret >=0)
@ -289,6 +293,11 @@ out:
cmd->rsp.ret = sock;
return ret;
epipe:
close(sock);
*stopped = 1;
return 0;
}
int lxc_try_cmd(const char *name, const char *lxcpath)