From: Chris Wright <chrisw@osdl.org>
Anything wrong with just setting a SIG_DFL handler? W.R.T. the kernel
pointer, either Andrew's patch which does put_user/__put_user depending
on context, or some ugly set_fs() should work. This simplistic approach
works for me, thoughts?
The wait_for_helper thread needs its own sighand struct, so that it's not
stomping on it's parent's SIGCHLD handler (which is intended to be SIG_IGN).
This is to make the parent keventd thread properly reaps children.
25-akpm/kernel/kmod.c | 13 +++++++++----
1 files changed, 9 insertions(+), 4 deletions(-)
diff -puN kernel/kmod.c~call_usermodehelper-retval-fix-3 kernel/kmod.c
--- 25/kernel/kmod.c~call_usermodehelper-retval-fix-3 Mon Oct 6 05:49:27 2003
+++ 25-akpm/kernel/kmod.c Mon Oct 6 05:49:27 2003
@@ -185,14 +185,19 @@ static int wait_for_helper(void *data)
sub_info->retval = 0;
pid = kernel_thread(____call_usermodehelper, sub_info, SIGCHLD);
- if (pid < 0)
+ if (pid < 0) {
sub_info->retval = pid;
- else
+ } else {
/* We don't have a SIGCHLD signal handler, so this
* always returns -ECHILD, but the important thing is
* that it blocks. */
- sys_wait4(pid, NULL, 0, NULL);
+ mm_segment_t fs;
+ fs = get_fs();
+ set_fs(KERNEL_DS);
+ sys_wait4(pid, &sub_info->retval, 0, NULL);
+ set_fs(fs);
+ }
complete(sub_info->complete);
return 0;
}
@@ -210,7 +215,7 @@ static void __call_usermodehelper(void *
* until that is done. */
if (sub_info->wait)
pid = kernel_thread(wait_for_helper, sub_info,
- CLONE_KERNEL | SIGCHLD);
+ CLONE_FS | CLONE_FILES | SIGCHLD);
else
pid = kernel_thread(____call_usermodehelper, sub_info,
CLONE_VFORK | SIGCHLD);
_