From: Johannes Berg <johannes.b...@intel.com>
Change os_rcv_fd() to os_rcv_fd_msg() that can more generally
receive any number of FDs in any kind of message.
Signed-off-by: Johannes Berg <johannes.b...@intel.com>
---
arch/um/drivers/port_kern.c | 14 +++++----
arch/um/drivers/xterm.c | 2 +-
arch/um/drivers/xterm_kern.c | 13 ++++++--
arch/um/include/shared/os.h | 3 +-
arch/um/kernel/ksyms.c | 2 +-
arch/um/os-Linux/file.c | 61 +++++++++++++++++++-----------------
6 files changed, 54 insertions(+), 41 deletions(-)
diff --git a/arch/um/drivers/port_kern.c b/arch/um/drivers/port_kern.c
index c52b3ff3c092..96087220c02d 100644
--- a/arch/um/drivers/port_kern.c
+++ b/arch/um/drivers/port_kern.c
@@ -45,15 +45,17 @@ struct connection {
static irqreturn_t pipe_interrupt(int irq, void *data)
{
struct connection *conn = data;
- int fd;
+ int n_fds = 1, fd = -1;
+ ssize_t ret;
- fd = os_rcv_fd(conn->socket[0], &conn->helper_pid);
- if (fd < 0) {
- if (fd == -EAGAIN)
+ ret = os_rcv_fd_msg(conn->socket[0], &fd, n_fds, &conn->helper_pid,
+ sizeof(conn->helper_pid));
+ if (ret != sizeof(conn->helper_pid)) {
+ if (ret == -EAGAIN)
return IRQ_NONE;
- printk(KERN_ERR "pipe_interrupt : os_rcv_fd returned %d\n",
- -fd);
+ printk(KERN_ERR "pipe_interrupt : os_rcv_fd_msg returned %d\n",
+ ret);
os_close_file(conn->fd);
}
diff --git a/arch/um/drivers/xterm.c b/arch/um/drivers/xterm.c
index 6918de5e2956..e4316c7981e8 100644
--- a/arch/um/drivers/xterm.c
+++ b/arch/um/drivers/xterm.c
@@ -156,7 +156,7 @@ static int xterm_open(int input, int output, int primary,
void *d,
new = xterm_fd(fd, &data->helper_pid);
if (new < 0) {
err = new;
- printk(UM_KERN_ERR "xterm_open : os_rcv_fd failed, err = %d\n",
+ printk(UM_KERN_ERR "xterm_open : xterm_fd failed, err = %d\n",
-err);
goto out_kill;
}
diff --git a/arch/um/drivers/xterm_kern.c b/arch/um/drivers/xterm_kern.c
index 8011e51993d5..3971252cb1a6 100644
--- a/arch/um/drivers/xterm_kern.c
+++ b/arch/um/drivers/xterm_kern.c
@@ -21,12 +21,19 @@ struct xterm_wait {
static irqreturn_t xterm_interrupt(int irq, void *data)
{
struct xterm_wait *xterm = data;
- int fd;
+ int fd = -1, n_fds = 1;
+ ssize_t ret;
- fd = os_rcv_fd(xterm->fd, &xterm->pid);
- if (fd == -EAGAIN)
+ ret = os_rcv_fd_msg(xterm->fd, &fd, n_fds,
+ &xterm->pid, sizeof(xterm->pid));
+ if (ret == -EAGAIN)
return IRQ_NONE;
+ if (ret < 0)
+ fd = ret;
+ else if (ret != sizeof(xterm->pid))
+ fd = -EMSGSIZE;
+
xterm->new_fd = fd;
complete(&xterm->ready);
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index 6516ff5a0ecc..fc4091c127c8 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -165,7 +165,8 @@ extern int os_create_unix_socket(const char *file, int len,
int close_on_exec);
extern int os_shutdown_socket(int fd, int r, int w);
extern int os_dup_file(int fd);
extern void os_close_file(int fd);
-extern int os_rcv_fd(int fd, int *helper_pid_out);
+ssize_t os_rcv_fd_msg(int fd, int *fds, unsigned int n_fds,
+ void *data, size_t data_len);
extern int os_connect_socket(const char *name);
extern int os_file_type(char *file);
extern int os_file_mode(const char *file, struct openflags *mode_out);
diff --git a/arch/um/kernel/ksyms.c b/arch/um/kernel/ksyms.c
index 3a85bde3e173..f2fb77da08cf 100644
--- a/arch/um/kernel/ksyms.c
+++ b/arch/um/kernel/ksyms.c
@@ -33,7 +33,7 @@ EXPORT_SYMBOL(os_shutdown_socket);
EXPORT_SYMBOL(os_create_unix_socket);
EXPORT_SYMBOL(os_connect_socket);
EXPORT_SYMBOL(os_accept_connection);
-EXPORT_SYMBOL(os_rcv_fd);
+EXPORT_SYMBOL(os_rcv_fd_msg);
EXPORT_SYMBOL(run_helper);
EXPORT_SYMBOL(os_major);
EXPORT_SYMBOL(os_minor);
diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c
index abf8676b834c..6d3c73910946 100644
--- a/arch/um/os-Linux/file.c
+++ b/arch/um/os-Linux/file.c
@@ -512,44 +512,47 @@ int os_shutdown_socket(int fd, int r, int w)
return 0;
}
-int os_rcv_fd(int fd, int *helper_pid_out)
+/**
+ * os_rcv_fd_msg - receive message with (optional) FDs
+ * @fd: the FD to receive from
+ * @fds: the array for FDs to write to
+ * @n_fds: number of FDs to receive (@fds array size)
+ * @data: the message buffer
+ * @data_len: the size of the message to receive
+ *
+ * Receive a message with FDs.
+ *
+ * Returns: the size of the received message, or an error code
+ */
+ssize_t os_rcv_fd_msg(int fd, int *fds, unsigned int n_fds,
+ void *data, size_t data_len)
{
- int new, n;
- char buf[CMSG_SPACE(sizeof(new))];
- struct msghdr msg;
+ char buf[CMSG_SPACE(sizeof(*fds) * n_fds)];
struct cmsghdr *cmsg;
- struct iovec iov;
-
- msg.msg_name = NULL;
- msg.msg_namelen = 0;
- iov = ((struct iovec) { .iov_base = helper_pid_out,
- .iov_len = sizeof(*helper_pid_out) });
- msg.msg_iov = &iov;
- msg.msg_iovlen = 1;
- msg.msg_control = buf;
- msg.msg_controllen = sizeof(buf);
- msg.msg_flags = 0;
+ struct iovec iov = {
+ .iov_base = data,
+ .iov_len = data_len,
+ };
+ struct msghdr msg = {
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ .msg_control = buf,
+ .msg_controllen = sizeof(buf),
+ };
+ int n;
n = recvmsg(fd, &msg, 0);
if (n < 0)
return -errno;
- else if (n != iov.iov_len)
- *helper_pid_out = -1;
cmsg = CMSG_FIRSTHDR(&msg);
- if (cmsg == NULL) {
- printk(UM_KERN_ERR "rcv_fd didn't receive anything, "
- "error = %d\n", errno);
- return -1;
- }
- if ((cmsg->cmsg_level != SOL_SOCKET) ||
- (cmsg->cmsg_type != SCM_RIGHTS)) {
- printk(UM_KERN_ERR "rcv_fd didn't receive a descriptor\n");
- return -1;
- }
+ if (!cmsg ||
+ cmsg->cmsg_level != SOL_SOCKET ||
+ cmsg->cmsg_type != SCM_RIGHTS)
+ return n;
- new = ((int *) CMSG_DATA(cmsg))[0];
- return new;
+ memcpy(fds, CMSG_DATA(cmsg), cmsg->cmsg_len);
+ return n;
}
int os_create_unix_socket(const char *file, int len, int close_on_exec)
--
2.45.2
