virConnectAuthCallbackDefault: Return failure if 'virGetPassword' returns NULL

virGetPassword can return NULL on linux or BSD if it fails. The caller
in virConnectAuthCallbackDefault does dereference it unconditionally.

Return failure if virGetPassword returns NULL.

Fixes: db72866310d1e520efa8ed2d4589bdb5e76a1c95
Closes: https://gitlab.com/libvirt/libvirt/-/issues/777
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>

diff --git a/src/libvirt.c b/src/libvirt.c
index 581fc6deea6860e3477e32680ab6cd101833bd71..375d3fa7ef34a05fc544707e9ae326a6afb86332 100644 (file)
--- a/src/libvirt.c
+++ b/src/libvirt.c
@@ -158,7 +158,9 @@ virConnectAuthCallbackDefault(virConnectCredentialPtr cred,
             if (fflush(stdout) != 0)
                 return -1;
 
-            bufptr = virGetPassword();
+            if (!(bufptr = virGetPassword()))
+                return -1;
+
             if (STREQ(bufptr, ""))
                 VIR_FREE(bufptr);
             break;