[GIT pull] core fix for 4.11

From: Thomas Gleixner
Date: Sun Apr 02 2017 - 03:21:15 EST


Linus,

please pull the latest core-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git core-urgent-for-linus

Prevent leaking kernel memory via /proc/$pid/syscall when the queried task
is not in a syscall.

Thanks,

tglx

------------------>
Kees Cook (1):
lib/syscall: Clear return values when no stack


lib/syscall.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/lib/syscall.c b/lib/syscall.c
index 17d5ff5fa6a3..2c6cd1b5c3ea 100644
--- a/lib/syscall.c
+++ b/lib/syscall.c
@@ -12,6 +12,7 @@ static int collect_syscall(struct task_struct *target, long *callno,

if (!try_get_task_stack(target)) {
/* Task has no stack, so the task isn't in a syscall. */
+ *sp = *pc = 0;
*callno = -1;
return 0;
}