[PULL 1/6] virtiofsd: Fix security.capability comparison

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

My security fix for the security.capability remap has a silly early
segfault in a simple case where there is an xattrmapping but it doesn't
remap the security.capability.

Fixes: e586edcb41054 ("virtiofs: drop remapped security.capability xattr as needed")
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210401145845.78445-1-dgilbert@redhat.com>
Reviewed-by: Connor Kuehl <ckuehl@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 tools/virtiofsd/passthrough_ll.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
index b144320e48..1553d2ef45 100644
--- a/tools/virtiofsd/passthrough_ll.c
+++ b/tools/virtiofsd/passthrough_ll.c
@@ -2636,7 +2636,8 @@ static void parse_xattrmap(struct lo_data *lo)
                 strerror(ret));
         exit(1);
     }
-    if (!strcmp(lo->xattr_security_capability, "security.capability")) {
+    if (!lo->xattr_security_capability ||
+        !strcmp(lo->xattr_security_capability, "security.capability")) {
         /* 1-1 mapping, don't need to do anything */
         free(lo->xattr_security_capability);
         lo->xattr_security_capability = NULL;
-- 
2.31.1