SOLARIS: Do not release NULL root vp on unmount

When we unmount, and afs_globalVp is NULL (e.g. because root.afs was
unavailable when the client was started), we will panic the machine if
we try to release it. So, if afs_globalVp is NULL when we hit our
unmount handler, don't touch it.

Reported by Andy Cobaugh.

Reviewed-on: http://gerrit.openafs.org/5117
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
(cherry picked from commit b621a2986099488426a026818532a9600db9aeba)

Change-Id: Iaa5db97e9fc87d1eb083d20a9fc6a49cbb5a066b
Reviewed-on: http://gerrit.openafs.org/5230
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>

diff --git a/src/afs/SOLARIS/osi_vfsops.c b/src/afs/SOLARIS/osi_vfsops.c
index 254c9acf8f341b4da432e906abcb81e5b357f111..9207914cd19d1d434151e3d63a17fd66daf79bee 100644 (file)
--- a/src/afs/SOLARIS/osi_vfsops.c
+++ b/src/afs/SOLARIS/osi_vfsops.c
@@ -128,11 +128,13 @@ afs_unmount(struct vfs *afsp, afs_ucred_t *credp)
     afsp->vfs_flag |= VFS_UNMOUNTED;
 #endif /* AFS_SUN58_ENV */
 
-    /* release the root vnode, which should be the last reference to us
-     * besides the caller of afs_unmount */
-    rootvp = afs_globalVp;
-    afs_globalVp = NULL;
-    AFS_RELE(rootvp);
+    if (afs_globalVp) {
+       /* release the root vnode, which should be the last reference to us
+        * besides the caller of afs_unmount */
+       rootvp = afs_globalVp;
+       afs_globalVp = NULL;
+       AFS_RELE(rootvp);
+    }
 
 #ifndef AFS_SUN58_ENV
     /* shutdown now, since gafs_freevfs() will not be called */