[PATCH v2 2/5] hibernation: ensure secretmem pages don't reach a snapshot

["Mike Rapoport (Microsoft)" <rppt@kernel.org>]

hibernation_available() checks for active secretmem users, but a secretmem
file can be created after this check and its pages may get into the
hibernation snapshot although they should not.

Recheck that hibernation_available() after userspace is frozen and abort
hibernation if it is not.

Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
---
 kernel/power/hibernate.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index d2479c69d71a..97de677e360f 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -412,6 +412,11 @@ int hibernation_snapshot(int platform_mode)
 	if (error)
 		goto Close;
 
+	if (!hibernation_available()) {
+		error = -EBUSY;
+		goto Thaw;
+	}
+
 	if (hibernation_test(TEST_FREEZER)) {
 
 		/*

-- 
2.53.0