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 049DA7D072 for ; Thu, 28 Jun 2018 05:23:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753506AbeF1FXB (ORCPT ); Thu, 28 Jun 2018 01:23:01 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:34196 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932799AbeF1FW7 (ORCPT ); Thu, 28 Jun 2018 01:22:59 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w5S5J97W057175 for ; Thu, 28 Jun 2018 01:22:58 -0400 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0b-001b2d01.pphosted.com with ESMTP id 2jvsa68eh3-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 28 Jun 2018 01:22:58 -0400 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 28 Jun 2018 06:22:56 +0100 Received: from b06cxnps4074.portsmouth.uk.ibm.com (9.149.109.196) by e06smtp05.uk.ibm.com (192.168.101.135) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 28 Jun 2018 06:22:51 +0100 Received: from d06av24.portsmouth.uk.ibm.com (mk.ibm.com [9.149.105.60]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w5S5MowJ31195314 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 28 Jun 2018 05:22:50 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 783E842049; Thu, 28 Jun 2018 06:22:41 +0100 (BST) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2CF1A42042; Thu, 28 Jun 2018 06:22:38 +0100 (BST) Received: from bangoria.in.ibm.com (unknown [9.124.31.233]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 28 Jun 2018 06:22:38 +0100 (BST) From: Ravi Bangoria To: srikar@linux.vnet.ibm.com, oleg@redhat.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, linux-arm-kernel@lists.infradead.org, linux-mips@linux-mips.org, linux@armlinux.org.uk, ralf@linux-mips.org, paul.burton@mips.com, Ravi Bangoria Subject: [PATCH v5 08/10] Uprobes/sdt: Prevent multiple reference counter for same uprobe Date: Thu, 28 Jun 2018 10:52:07 +0530 X-Mailer: git-send-email 2.14.4 In-Reply-To: <20180628052209.13056-1-ravi.bangoria@linux.ibm.com> References: <20180628052209.13056-1-ravi.bangoria@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18062805-0020-0000-0000-0000029FC7AB X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18062805-0021-0000-0000-000020EC49CD Message-Id: <20180628052209.13056-9-ravi.bangoria@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-06-28_02:,, 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=8.0.1-1806210000 definitions=main-1806280059 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 61f9b0024794..feefeeb6d2c6 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -662,6 +662,12 @@ 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; } @@ -1076,6 +1082,9 @@ 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. -- 2.14.4 -- 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