When a path is part of a multipath device, it must not change it's wwid.
If it can, when multipathd is reconfigured, you can end up with two
multipath devices owning the same path, eventually leading to a crash.

Signed-off-by: Benjamin Marzinski <bmarz...@redhat.com>
---
 libmultipath/dmparser.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/libmultipath/dmparser.c b/libmultipath/dmparser.c
index 9e79ecd..87e8398 100644
--- a/libmultipath/dmparser.c
+++ b/libmultipath/dmparser.c
@@ -380,6 +380,14 @@ disassemble_map (vector pathvec, char * params, struct 
multipath * mpp,
                                strncpy(pp->wwid, mpp->wwid,
                                        WWID_SIZE - 1);
 
+                       /*
+                        * Do not allow in-use patch to change wwid
+                        */
+                       else if (strcmp(pp->wwid, mpp->wwid) != 0) {
+                               condlog(0, "%s: path wwid appears to have 
changed. Using map wwid.\n", pp->dev_t);
+                               strncpy(pp->wwid, mpp->wwid, WWID_SIZE);
+                       }
+
                        pgp->id ^= (long)pp;
                        pp->pgindex = i + 1;
 
-- 
1.8.3.1

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