From: Johannes Berg <johannes.b...@intel.com>
The previous fix here was only partially correct, it did
result in returning a proper error value in case of error,
but it also clobbered the pid that we need to return from
this function (not just zero for success).
As a result, it returned 0 here, but later this is treated
as a pid and used to kill the process, but since it's now
0 we kill(0, SIGKILL), which makes UML kill itself rather
than just the helper thread.
Fix that and make it more obvious by using a separate
variable for the pid.
Fixes: ccf1236ecac4 ("um: fix error return code in winch_tramp()")
Reported-and-tested-by: Nathan Chancellor <nat...@kernel.org>
Signed-off-by: Johannes Berg <johannes.b...@intel.com>
---
arch/um/drivers/chan_user.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/arch/um/drivers/chan_user.c b/arch/um/drivers/chan_user.c
index 6040817c036f..25727ed648b7 100644
--- a/arch/um/drivers/chan_user.c
+++ b/arch/um/drivers/chan_user.c
@@ -220,7 +220,7 @@ static int winch_tramp(int fd, struct tty_port *port, int
*fd_out,
unsigned long *stack_out)
{
struct winch_data data;
- int fds[2], n, err;
+ int fds[2], n, err, pid;
char c;
err = os_pipe(fds, 1, 1);
@@ -238,8 +238,9 @@ static int winch_tramp(int fd, struct tty_port *port, int
*fd_out,
* problem with /dev/net/tun, which if held open by this
* thread, prevents the TUN/TAP device from being reused.
*/
- err = run_helper_thread(winch_thread, &data, CLONE_FILES, stack_out);
- if (err < 0) {
+ pid = run_helper_thread(winch_thread, &data, CLONE_FILES, stack_out);
+ if (pid < 0) {
+ err = pid;
printk(UM_KERN_ERR "fork of winch_thread failed - errno = %d\n",
-err);
goto out_close;
@@ -263,7 +264,7 @@ static int winch_tramp(int fd, struct tty_port *port, int
*fd_out,
goto out_close;
}
- return err;
+ return pid;
out_close:
close(fds[1]);
--
2.36.1
_______________________________________________
linux-um mailing list
linux-um@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-um
