From 9df99d6ed0b349a89d921e67acbcc3f1375c33cd Mon Sep 17 00:00:00 2001
From: Alan Somers <asomers@FreeBSD.org>
Date: Wed, 18 Jan 2017 22:10:18 +0000
Subject: [PATCH] Fix an unchecked return value in zfsd

It's pretty unlikely to actually hit this, but good to check it anyway

Reported by:	Coverity
CID:		1362018
MFC after:	4 weeks
Sponsored by:	Spectra Logic Corp
---
 cddl/usr.sbin/zfsd/case_file.cc | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/cddl/usr.sbin/zfsd/case_file.cc b/cddl/usr.sbin/zfsd/case_file.cc
index 86c74b12230..0cd659622e9 100644
--- a/cddl/usr.sbin/zfsd/case_file.cc
+++ b/cddl/usr.sbin/zfsd/case_file.cc
@@ -656,8 +656,11 @@ CaseFile::DeSerializeFile(const char *fileName)
 		uint64_t vdevGUID;
 		nvlist_t *vdevConf;
 
-		sscanf(fileName, "pool_%" PRIu64 "_vdev_%" PRIu64 ".case",
-		       &poolGUID, &vdevGUID);
+		if (sscanf(fileName, "pool_%" PRIu64 "_vdev_%" PRIu64 ".case",
+		       &poolGUID, &vdevGUID) != 2) {
+			throw ZfsdException("CaseFile::DeSerialize: "
+			    "Unintelligible CaseFile filename %s.\n", fileName);
+		}
 		existingCaseFile = Find(Guid(poolGUID), Guid(vdevGUID));
 		if (existingCaseFile != NULL) {
 			/*