[Libvir] PATCH: BZ 427107: fix crash wrt auth callback

If the application does not supply an authentication callback, and tries to connect to a server with PolicyKit auth turned on it will try to deference a NULL pointer with predictably crashtastic results: https://bugzilla.redhat.com/show_bug.cgi?id=427107 This patch has been tested by bug reporter to fix the issue Index: src/remote_internal.c =================================================================== RCS file: /data/cvs/libvirt/src/remote_internal.c,v retrieving revision 1.49 diff -u -p -r1.49 remote_internal.c --- src/remote_internal.c 17 Dec 2007 17:41:02 -0000 1.49 +++ src/remote_internal.c 31 Dec 2007 20:30:19 -0000 @@ -3347,24 +3347,26 @@ remoteAuthPolkit (virConnectPtr conn, st }; remoteDebug(priv, "Client initialize PolicyKit authentication"); - for (i = 0 ; i < auth->ncredtype ; i++) { - if (auth->credtype[i] == VIR_CRED_EXTERNAL) - allowcb = 1; - } + if (auth && auth->cb) { + /* Check if the neccessary credential type for PolicyKit is supported */ + for (i = 0 ; i < auth->ncredtype ; i++) { + if (auth->credtype[i] == VIR_CRED_EXTERNAL) + allowcb = 1; + } - /* Run the authentication callback */ - if (allowcb) { - if (auth && auth->cb && - (*(auth->cb))(&cred, 1, auth->cbdata) < 0) { - __virRaiseError (in_open ? NULL : conn, NULL, NULL, VIR_FROM_REMOTE, - VIR_ERR_AUTH_FAILED, VIR_ERR_ERROR, NULL, NULL, NULL, 0, 0, - "Failed to collect auth credentials"); - return -1; + if (allowcb) { + /* Run the authentication callback */ + if ((*(auth->cb))(&cred, 1, auth->cbdata) < 0) { + __virRaiseError (in_open ? NULL : conn, NULL, NULL, VIR_FROM_REMOTE, + VIR_ERR_AUTH_FAILED, VIR_ERR_ERROR, NULL, NULL, NULL, 0, 0, + "Failed to collect auth credentials"); + return -1; + } } else { - remoteDebug(priv, "No auth callback provided for PolicyKit"); + remoteDebug(priv, "Client auth callback does not support PolicyKit"); } } else { - remoteDebug(priv, "Client auth callback does not support PolicyKit"); + remoteDebug(priv, "No auth callback provided"); } memset (&ret, 0, sizeof ret); Regards, Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|