um: Fix hung task in fix_range_common()

If do_ops() fails we have to release current->mm->mmap_sem
otherwise the failing task will never terminate.

Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Richard Weinberger 2014-07-20 13:16:20 +02:00
parent 284e6d3951
commit 468f65976a

View File

@ -12,6 +12,7 @@
#include <mem_user.h>
#include <os.h>
#include <skas.h>
#include <kern_util.h>
struct host_vm_change {
struct host_vm_op {
@ -286,8 +287,11 @@ void fix_range_common(struct mm_struct *mm, unsigned long start_addr,
/* This is not an else because ret is modified above */
if (ret) {
printk(KERN_ERR "fix_range_common: failed, killing current "
"process\n");
"process: %d\n", task_tgid_vnr(current));
/* We are under mmap_sem, release it such that current can terminate */
up_write(&current->mm->mmap_sem);
force_sig(SIGKILL, current);
do_signal();
}
}