From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id DBF427DF8E for ; Wed, 20 Jun 2018 03:58:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754282AbeFTD5y (ORCPT ); Tue, 19 Jun 2018 23:57:54 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:48160 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754600AbeFTD5N (ORCPT ); Tue, 19 Jun 2018 23:57:13 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w5K3t8kE014623 for ; Tue, 19 Jun 2018 23:57:12 -0400 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0b-001b2d01.pphosted.com with ESMTP id 2jqeedhsrd-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 19 Jun 2018 23:57:12 -0400 Received: from localhost by e06smtp01.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Wed, 20 Jun 2018 04:57:03 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w5K3v2YQ33423552 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 20 Jun 2018 03:57:02 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D6494AE04D; Wed, 20 Jun 2018 04:45:44 +0100 (BST) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 199C0AE045; Wed, 20 Jun 2018 04:45:42 +0100 (BST) Received: from bangoria.in.ibm.com (unknown [9.124.31.59]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Wed, 20 Jun 2018 04:45:41 +0100 (BST) From: Ravi Bangoria To: oleg@redhat.com, srikar@linux.vnet.ibm.com, rostedt@goodmis.org, mhiramat@kernel.org Cc: peterz@infradead.org, mingo@redhat.com, acme@kernel.org, alexander.shishkin@linux.intel.com, jolsa@redhat.com, namhyung@kernel.org, linux-kernel@vger.kernel.org, corbet@lwn.net, linux-doc@vger.kernel.org, ananth@linux.vnet.ibm.com, alexis.berlemont@gmail.com, naveen.n.rao@linux.vnet.ibm.com, Ravi Bangoria Subject: [PATCH v4 7/9] Uprobes/sdt: Prevent multiple reference counter for same uprobe Date: Wed, 20 Jun 2018 09:26:27 +0530 X-Mailer: git-send-email 2.14.4 In-Reply-To: <20180620035629.7844-1-ravi.bangoria@linux.ibm.com> References: <20180620035629.7844-1-ravi.bangoria@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18062003-4275-0000-0000-0000028FB0AC X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18062003-4276-0000-0000-00003796F6CD Message-Id: <20180620035629.7844-8-ravi.bangoria@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-06-20_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1805220000 definitions=main-1806200044 Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org We assume to have only one reference counter for one uprobe. Don't allow user to register multiple uprobes having same inode+offset but different reference counter. Signed-off-by: Ravi Bangoria --- kernel/events/uprobes.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index efa1e04..edc33ad 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -687,6 +687,12 @@ static struct uprobe *alloc_uprobe(struct inode *inode, loff_t offset, cur_uprobe = insert_uprobe(uprobe); /* a uprobe exists for this inode:offset combination */ if (cur_uprobe) { + if (cur_uprobe->ref_ctr_offset != uprobe->ref_ctr_offset) { + pr_warn("Err: Reference counter mismatch.\n"); + put_uprobe(cur_uprobe); + kfree(uprobe); + return ERR_PTR(-EINVAL); + } kfree(uprobe); uprobe = cur_uprobe; } @@ -1101,6 +1107,9 @@ static int __uprobe_register(struct inode *inode, loff_t offset, uprobe = alloc_uprobe(inode, offset, ref_ctr_offset); if (!uprobe) return -ENOMEM; + if (IS_ERR(uprobe)) + return PTR_ERR(uprobe); + /* * We can race with uprobe_unregister()->delete_uprobe(). * Check uprobe_is_active() and retry if it is false. -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html