From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [46.235.227.227]) by sourceware.org (Postfix) with ESMTPS id 8DBF438708B4 for ; Tue, 15 Dec 2020 18:45:13 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 8DBF438708B4 Received: from noise.cbg.collabora.co.uk (unknown [IPv6:2001:4d48:ad5c:ef00:8e70:5aff:fe59:c29c]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: vivek) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 306901F4561F for ; Tue, 15 Dec 2020 18:45:09 +0000 (GMT) From: =?UTF-8?q?Vivek=20Das=C2=A0Mohapatra?= To: libc-alpha Subject: [RFC][PATCH v6 15/20] Suppress audit calls when a (new) namespace is empty Date: Tue, 15 Dec 2020 18:44:55 +0000 Message-Id: <20201215184500.25915-16-vivek@collabora.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20201215184500.25915-1-vivek@collabora.com> References: <20201215184500.25915-1-vivek@collabora.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-13.6 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, SPF_HELO_PASS, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Dec 2020 18:45:15 -0000 When preparing an RTLD_SHARED proxy in a new namespace it is possible for the target namespace to be empty: This can happen for RTLD_SHARED + LM_ID_NEWLM. The audit infrastructure should not be invoked at this point (as there's nothing there to audit yet). --- elf/dl-load.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/elf/dl-load.c b/elf/dl-load.c index 68587831fd..9bd4884a88 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -1127,8 +1127,11 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, && __glibc_unlikely (GLRO(dl_naudit) > 0)) { struct link_map *head = GL(dl_ns)[nsid]._ns_loaded; - /* Do not call the functions for any auditing object. */ - if (head->l_auditing == 0) + /* Do not call the functions for any auditing object. + Do not try to call auditing functions if the namespace + is currently empty. This can hapen when opening the first + DSO in a new namespace. */ + if (head && head->l_auditing == 0) { struct audit_ifaces *afct = GLRO(dl_audit); for (unsigned int cnt = 0; cnt < GLRO(dl_naudit); ++cnt) -- 2.20.1