The patch titled
Subject: usermodehelper: don't use CLONE_VFORK for ____call_usermodehelper()
has been removed from the -mm tree. Its filename was
usermodehelper-dont-use-clone_vfork-for-____call_usermodehelper.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Oleg Nesterov <oleg@xxxxxxxxxx>
Subject: usermodehelper: don't use CLONE_VFORK for ____call_usermodehelper()
After "kernel/kmod: fix use-after-free of the sub_infostructure"
CLONE_VFORK in __call_usermodehelper() buys nothing, we rely on on
umh_complete() in ____call_usermodehelper() anyway.
Remove it. This also eliminates the unnecessary sleep/wakeup in the
likely case, and this allows the next change.
While at it, kill the "int wait" locals in ____call_usermodehelper() and
__call_usermodehelper(), they can safely use sub_info->wait.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/kmod.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)
diff -puN kernel/kmod.c~usermodehelper-dont-use-clone_vfork-for-____call_usermodehelper kernel/kmod.c
--- a/kernel/kmod.c~usermodehelper-dont-use-clone_vfork-for-____call_usermodehelper
+++ a/kernel/kmod.c
@@ -223,7 +223,6 @@ static void umh_complete(struct subproce
static int ____call_usermodehelper(void *data)
{
struct subprocess_info *sub_info = data;
- int wait = sub_info->wait & ~UMH_KILLABLE;
struct cred *new;
int retval;
@@ -267,7 +266,7 @@ static int ____call_usermodehelper(void
out:
sub_info->retval = retval;
/* wait_for_helper() will call umh_complete if UHM_WAIT_PROC. */
- if (wait != UMH_WAIT_PROC)
+ if (!(sub_info->wait & UMH_WAIT_PROC))
umh_complete(sub_info);
if (!retval)
return 0;
@@ -323,18 +322,13 @@ static void __call_usermodehelper(struct
{
struct subprocess_info *sub_info =
container_of(work, struct subprocess_info, work);
- int wait = sub_info->wait & ~UMH_KILLABLE;
pid_t pid;
- /* CLONE_VFORK: wait until the usermode helper has execve'd
- * successfully We need the data structures to stay around
- * until that is done. */
- if (wait == UMH_WAIT_PROC)
+ if (sub_info->wait & UMH_WAIT_PROC)
pid = kernel_thread(wait_for_helper, sub_info,
CLONE_FS | CLONE_FILES | SIGCHLD);
else {
- pid = kernel_thread(call_helper, sub_info,
- CLONE_VFORK | SIGCHLD);
+ pid = kernel_thread(call_helper, sub_info, SIGCHLD);
/* Worker thread stopped blocking khelper thread. */
kmod_thread_locker = NULL;
}
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
origin.patch
mmfs-introduce-helpers-around-the-i_mmap_mutex.patch
mm-use-new-helper-functions-around-the-i_mmap_mutex.patch
mm-convert-i_mmap_mutex-to-rwsem.patch
mm-rmap-share-the-i_mmap_rwsem.patch
uprobes-share-the-i_mmap_rwsem.patch
mm-xip-share-the-i_mmap_rwsem.patch
mm-memory-failure-share-the-i_mmap_rwsem.patch
mm-nommu-share-the-i_mmap_rwsem.patch
mm-memoryc-share-the-i_mmap_rwsem.patch
remove-unnecessary-is_valid_nodemask.patch
oom-dont-assume-that-a-coredumping-thread-will-exit-soon.patch
oom-dont-assume-that-a-coredumping-thread-will-exit-soon-v2.patch
oom-dont-assume-that-a-coredumping-thread-will-exit-soon-v2-fix.patch
oom-kill-the-insufficient-and-no-longer-needed-pt_trace_exit-check.patch
linux-next.patch
all-arches-signal-move-restart_block-to-struct-task_struct.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
