From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51CF1C10F14 for ; Mon, 8 Apr 2019 14:42:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1873120879 for ; Mon, 8 Apr 2019 14:42:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727400AbfDHOmu (ORCPT ); Mon, 8 Apr 2019 10:42:50 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:5700 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726373AbfDHOmt (ORCPT ); Mon, 8 Apr 2019 10:42:49 -0400 Received: from DGGEMS410-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id E6A2BEBEA5D7269BF843; Mon, 8 Apr 2019 22:42:46 +0800 (CST) Received: from [127.0.0.1] (10.177.31.96) by DGGEMS410-HUB.china.huawei.com (10.3.19.210) with Microsoft SMTP Server id 14.3.408.0; Mon, 8 Apr 2019 22:42:44 +0800 Subject: Re: [PATCH] fmc: Fix possible NULL pointer dereference To: , , , References: <20190408143701.15372-1-yuehaibing@huawei.com> CC: From: YueHaibing Message-ID: <28aafb84-4d15-0340-66fd-0d4d02c1ecce@huawei.com> Date: Mon, 8 Apr 2019 22:42:42 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <20190408143701.15372-1-yuehaibing@huawei.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.31.96] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org +cc Alessandro Rubini On 2019/4/8 22:37, Yue Haibing wrote: > From: YueHaibing > > Syzkaller report this: > > kasan: GPF could be caused by NULL-ptr deref or user memory access > general protection fault: 0000 [#1] SMP KASAN PTI > CPU: 0 PID: 3692 Comm: syz-executor.0 Tainted: G C 5.0.0+ #5 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 > RIP: 0010:ff_dev_create+0xf7/0x2e0 [fmc_fakedev] > Code: 00 e8 4d 2d a7 f6 ba c0 0c 00 00 48 c7 c7 00 20 15 c1 be e8 04 00 00 e8 e7 8e c7 f6 48 8d b8 a8 04 00 00 48 89 fa 48 c1 ea 03 <80> 3c 1a 00 0f 85 90 01 00 00 48 8d 78 50 4c 89 b0 a8 04 00 00 48 > RSP: 0018:ffff8881ea7a78e8 EFLAGS: 00010206 > RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff815c9540 > RDX: 0000000000000095 RSI: ffffc900013ec000 RDI: 00000000000004a8 > RBP: 0000000000000000 R08: ffffed103ee458b8 R09: ffffed103ee458b8 > R10: 0000000000000001 R11: ffffed103ee458b7 R12: ffff8881e4865d80 > R13: dffffc0000000000 R14: ffff8881e4865da0 R15: ffffffffc115b0b0 > FS: 00007fb08a226700(0000) GS:ffff8881f7200000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f6bd5a37890 CR3: 00000001c5632006 CR4: 00000000007606f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > PKRU: 55555554 > Call Trace: > ff_init+0x10b/0x3a0 [fmc_fakedev] > do_one_initcall+0xbc/0x47d init/main.c:887 > do_init_module+0x1b5/0x547 kernel/module.c:3456 > load_module+0x6405/0x8c10 kernel/module.c:3804 > __do_sys_finit_module+0x162/0x190 kernel/module.c:3898 > do_syscall_64+0x9f/0x450 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x462e99 > Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007fb08a225c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 > RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99 > RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 > RBP: 00007fb08a225c70 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb08a2266bc > R13: 00000000004bcefa R14: 00000000006f6fb0 R15: 0000000000000004 > Modules linked in: fmc_fakedev(+) fmc iptable_security iptable_raw iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_filter bpfilter ip6_vti ip_vti ip_gre ipip sit tunnel4 ip_tunnel hsr veth netdevsim vxcan batman_adv cfg80211 rfkill chnl_net caif nlmon dummy team bonding vcan bridge stp llc ip6_gre gre ip6_tunnel tunnel6 tun joydev mousedev ppdev tpm kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel ide_pci_generic piix aes_x86_64 crypto_simd cryptd ide_core psmouse glue_helper input_leds intel_agp serio_raw intel_gtt i2c_piix4 ata_generic agpgart pata_acpi rtc_cmos parport_pc floppy parport sch_fq_codel ip_tables x_tables sha1_ssse3 sha1_generic ipv6 [last unloaded: lib80211] > Dumping ftrace buffer: > (ftrace buffer empty) > ---[ end trace 297e0e50d0ab9883 ]--- > > If kmemdup failed, we should rollback all the alloced resources. > > Reported-by: Hulk Robot > Fixes: 6c62a895e572 ("FMC: add a software carrier driver") > Signed-off-by: YueHaibing > --- > drivers/fmc/fmc-fakedev.c | 18 ++++++++++++++---- > 1 file changed, 14 insertions(+), 4 deletions(-) > > diff --git a/drivers/fmc/fmc-fakedev.c b/drivers/fmc/fmc-fakedev.c > index 941d093..43d99fe 100644 > --- a/drivers/fmc/fmc-fakedev.c > +++ b/drivers/fmc/fmc-fakedev.c > @@ -273,15 +273,18 @@ static struct ff_dev *ff_dev_create(void) > ff->dev.release = ff_dev_release; > > ret = device_register(&ff->dev); > - if (ret < 0) { > - put_device(&ff->dev); > - return ERR_PTR(ret); > - } > + if (ret < 0) > + goto failed_register; > > /* Create fmc structures that refer to this new "hw" device */ > for (i = 0; i < ff_nr_dev; i++) { > fmc = kmemdup(&ff_template_fmc, sizeof(ff_template_fmc), > GFP_KERNEL); > + if (!fmc) { > + ret = -ENOMEM > + goto free_fmc; > + } > + > fmc->hwdev = &ff->dev; > fmc->carrier_data = ff; > fmc->nr_slots = ff_nr_dev; > @@ -294,6 +297,13 @@ static struct ff_dev *ff_dev_create(void) > ff_template_fmc.device_id++; > } > return ff; > + > +free_fmc: > + for (i--; i >= 0; i--) > + kfree(ff->fmc[i]); > +failed_register: > + put_device(&ff->dev); > + return ERR_PTR(ret); > } > > /* init and exit */ >