summaryrefslogtreecommitdiff
path: root/mm/madvise.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/madvise.c')
-rw-r--r--mm/madvise.c18
1 files changed, 18 insertions, 0 deletions
diff --git a/mm/madvise.c b/mm/madvise.c
index 4bb30ed6c8d2..8cbd8c1bfe15 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -27,6 +27,7 @@
#include <linux/swapops.h>
#include <linux/shmem_fs.h>
#include <linux/mmu_notifier.h>
+#include <linux/sched/mm.h>
#include <asm/tlb.h>
@@ -1090,6 +1091,23 @@ int do_madvise(unsigned long start, size_t len_in, int behavior)
if (write) {
if (down_write_killable(&current->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(&current->mm->mmap_sem);
+ return -EINTR;
+ }
} else {
down_read(&current->mm->mmap_sem);
}