From a56e339419c1a90f8a85f86621f3c73945e07b23 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Tue, 2 Dec 2014 21:54:36 -0500 Subject: [PATCH] fix uninitialized output from sched_getaffinity the sched_getaffinity syscall only fills a cpu set up to the set size used/supported by the kernel. the rest is left untouched and userspace is responsible for zero-filling it based on the return value of the syscall. --- src/sched/affinity.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/sched/affinity.c b/src/sched/affinity.c index 3b402111..737e41b5 100644 --- a/src/sched/affinity.c +++ b/src/sched/affinity.c @@ -1,5 +1,6 @@ #define _GNU_SOURCE #include +#include #include "pthread_impl.h" #include "syscall.h" @@ -16,7 +17,10 @@ int pthread_setaffinity_np(pthread_t td, size_t size, const cpu_set_t *set) int sched_getaffinity(pid_t tid, size_t size, cpu_set_t *set) { long ret = __syscall(SYS_sched_getaffinity, tid, size, set); - if (ret > 0) ret = 0; + if (ret > 0) { + if (ret < size) memset((char *)set+ret, 0, size-ret); + ret = 0; + } return __syscall_ret(ret); }