diff --git a/mm/madvise.c b/mm/madvise.c index 4bb30ed6c8d21..8cbd8c1bfe159 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -27,6 +27,7 @@ #include #include #include +#include #include @@ -1090,6 +1091,23 @@ int do_madvise(unsigned long start, size_t len_in, int behavior) if (write) { if (down_write_killable(¤t->mm->mmap_sem)) return -EINTR; + + /* + * We may have stolen the mm from another process + * that is undergoing core dumping. + * + * Right now that's io_ring, in the future it may + * be remote process management and not "current" + * at all. + * + * We need to fix core dumping to not do this, + * but for now we have the mmget_still_valid() + * model. + */ + if (!mmget_still_valid(current->mm)) { + up_write(¤t->mm->mmap_sem); + return -EINTR; + } } else { down_read(¤t->mm->mmap_sem); }