OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[PATCH] Fix ____call_usermodehelper errors being silently ignored 

If ____call_usermodehelper fails, we're not interested in the child
process' exit value, but the real error, so let's stop wait_for_helper from
overwriting it in that case.

Issue discovered by Benedikt Böhm while working on a Linux-VServer usermode
helper.

Signed-off-by: Björn Steinbrink <B.Steinbrink@gmx.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Björn Steinbrink 2006-09-29 02:00:46 -07:00 committed by Linus Torvalds
parent 3e26a423e7
commit 111dbe0c8a
1 changed files with 11 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
kernel/kmod.c
View File

@ -176,6 +176,8 @@ static int wait_for_helper(void *data)
if (pid < 0) {
sub_info->retval = pid;
} else {
int ret;
/*
* Normally it is bogus to call wait4() from in-kernel because
* wait4() wants to write the exit code to a userspace address.
@ -185,7 +187,15 @@ static int wait_for_helper(void *data)
*
* Thus the __user pointer cast is valid here.
*/
sys_wait4(pid, (int __user *) &sub_info->retval, 0, NULL);
sys_wait4(pid, (int __user *)&ret, 0, NULL);
/*
* If ret is 0, either ____call_usermodehelper failed and the
* real error code is already in sub_info->retval or
* sub_info->retval is 0 anyway, so don't mess with it then.
*/
if (ret)
sub_info->retval = ret;
}
complete(sub_info->complete);