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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61B93CCA47B for ; Thu, 9 Jun 2022 13:18:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343716AbiFINSE (ORCPT ); Thu, 9 Jun 2022 09:18:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46506 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239163AbiFINR7 (ORCPT ); Thu, 9 Jun 2022 09:17:59 -0400 Received: from zg8tndyumtaxlji0oc4xnzya.icoremail.net (zg8tndyumtaxlji0oc4xnzya.icoremail.net [46.101.248.176]) by lindbergh.monkeyblade.net (Postfix) with SMTP id 5333F3CBE2A; Thu, 9 Jun 2022 06:17:54 -0700 (PDT) Received: by ajax-webmail-mail-app3 (Coremail) ; Thu, 9 Jun 2022 21:17:27 +0800 (GMT+08:00) X-Originating-IP: [106.117.78.144] Date: Thu, 9 Jun 2022 21:17:27 +0800 (GMT+08:00) X-CM-HeaderCharset: UTF-8 From: duoming@zju.edu.cn To: "Paolo Abeni" Cc: linux-kernel@vger.kernel.org, jreuter@yaina.de, ralf@linux-mips.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, netdev@vger.kernel.org, linux-hams@vger.kernel.org, thomas@osterried.de Subject: Re: [PATCH v3] net: ax25: Fix deadlock caused by skb_recv_datagram in ax25_recvmsg X-Priority: 3 X-Mailer: Coremail Webmail Server Version XT5.0.13 build 20210104(ab8c30b6) Copyright (c) 2002-2022 www.mailtech.cn zju.edu.cn In-Reply-To: <22175690a4e89a78abcb8244dfd0bdd0005267a5.camel@redhat.com> References: <20220608012923.17505-1-duoming@zju.edu.cn> <22175690a4e89a78abcb8244dfd0bdd0005267a5.camel@redhat.com> Content-Transfer-Encoding: base64 Content-Type: text/plain; charset=UTF-8 MIME-Version: 1.0 Message-ID: <4ccdba76.5ee33.181489cd6e4.Coremail.duoming@zju.edu.cn> X-Coremail-Locale: zh_CN X-CM-TRANSID: cC_KCgAHbtjn8qFiI3DWAQ--.44508W X-CM-SenderInfo: qssqjiasttq6lmxovvfxof0/1tbiAgIQAVZdtaIJ7gABsr X-Coremail-Antispam: 1Ur529EdanIXcx71UUUUU7IcSsGvfJ3iIAIbVAYjsxI4VWxJw CS07vEb4IE77IF4wCS07vE1I0E4x80FVAKz4kxMIAIbVAFxVCaYxvI4VCIwcAKzIAtYxBI daVFxhVjvjDU= Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org SGVsbG8sCgpPbiBUaHUsIDA5IEp1biAyMDIyIDEwOjQxOjAyICswMjAwIFBhb2xvIHdyb3RlOgoK PiBPbiBXZWQsIDIwMjItMDYtMDggYXQgMDk6MjkgKzA4MDAsIER1b21pbmcgWmhvdSB3cm90ZToK PiA+IFRoZSBza2JfcmVjdl9kYXRhZ3JhbSgpIGluIGF4MjVfcmVjdm1zZygpIHdpbGwgaG9sZCBs b2NrX3NvY2sKPiA+IGFuZCBibG9jayB1bnRpbCBpdCByZWNlaXZlcyBhIHBhY2tldCBmcm9tIHRo ZSByZW1vdGUuIElmIHRoZSBjbGllbnQKPiA+IGRvZXNuYHQgY29ubmVjdCB0byBzZXJ2ZXIgYW5k IGNhbGxzIHJlYWQoKSBkaXJlY3RseSwgaXQgd2lsbCBub3QKPiA+IHJlY2VpdmUgYW55IHBhY2tl dHMgZm9yZXZlci4gQXMgYSByZXN1bHQsIHRoZSBkZWFkbG9jayB3aWxsIGhhcHBlbi4KPiA+IAo+ ID4gVGhlIGZhaWwgbG9nIGNhdXNlZCBieSBkZWFkbG9jayBpcyBzaG93biBiZWxvdzoKPiA+IAo+ ID4gWyAgMzY5LjYwNjk3M10gSU5GTzogdGFzayBheDI1X2RlYWRsb2NrOjE1NyBibG9ja2VkIGZv ciBtb3JlIHRoYW4gMjQ1IHNlY29uZHMuCj4gPiBbICAzNjkuNjA4OTE5XSAiZWNobyAwID4gL3By b2Mvc3lzL2tlcm5lbC9odW5nX3Rhc2tfdGltZW91dF9zZWNzIiBkaXNhYmxlcyB0aGlzIG1lc3Nh Z2UuCj4gPiBbICAzNjkuNjEzMDU4XSBDYWxsIFRyYWNlOgo+ID4gWyAgMzY5LjYxMzMxNV0gIDxU QVNLPgo+ID4gWyAgMzY5LjYxNDA3Ml0gIF9fc2NoZWR1bGUrMHgyZjkvMHhiMjAKPiA+IFsgIDM2 OS42MTUwMjldICBzY2hlZHVsZSsweDQ5LzB4YjAKPiA+IFsgIDM2OS42MTU3MzRdICBfX2xvY2tf c29jaysweDkyLzB4MTAwCj4gPiBbICAzNjkuNjE2NzYzXSAgPyBkZXN0cm95X3NjaGVkX2RvbWFp bnNfcmN1KzB4MjAvMHgyMAo+ID4gWyAgMzY5LjYxNzk0MV0gIGxvY2tfc29ja19uZXN0ZWQrMHg2 ZS8weDcwCj4gPiBbICAzNjkuNjE4ODA5XSAgYXgyNV9iaW5kKzB4YWEvMHgyMTAKPiA+IFsgIDM2 OS42MTk3MzZdICBfX3N5c19iaW5kKzB4Y2EvMHhmMAo+ID4gWyAgMzY5LjYyMDAzOV0gID8gZG9f ZnV0ZXgrMHhhZS8weDFiMAo+ID4gWyAgMzY5LjYyMDM4N10gID8gX194NjRfc3lzX2Z1dGV4KzB4 N2MvMHgxYzAKPiA+IFsgIDM2OS42MjA2MDFdICA/IGZwcmVnc19hc3NlcnRfc3RhdGVfY29uc2lz dGVudCsweDE5LzB4NDAKPiA+IFsgIDM2OS42MjA2MTNdICBfX3g2NF9zeXNfYmluZCsweDExLzB4 MjAKPiA+IFsgIDM2OS42MjE3OTFdICBkb19zeXNjYWxsXzY0KzB4M2IvMHg5MAo+ID4gWyAgMzY5 LjYyMjQyM10gIGVudHJ5X1NZU0NBTExfNjRfYWZ0ZXJfaHdmcmFtZSsweDQ2LzB4YjAKPiA+IFsg IDM2OS42MjMzMTldIFJJUDogMDAzMzoweDdmNDNjOGFhOGFmNwo+ID4gWyAgMzY5LjYyNDMwMV0g UlNQOiAwMDJiOjAwMDA3ZjQzYzgxOTdlZjggRUZMQUdTOiAwMDAwMDI0NiBPUklHX1JBWDogMDAw MDAwMDAwMDAwMDAzMQo+ID4gWyAgMzY5LjYyNTc1Nl0gUkFYOiBmZmZmZmZmZmZmZmZmZmRhIFJC WDogMDAwMDAwMDAwMDAwMDAwMCBSQ1g6IDAwMDA3ZjQzYzhhYThhZjcKPiA+IFsgIDM2OS42MjY3 MjRdIFJEWDogMDAwMDAwMDAwMDAwMDAxMCBSU0k6IDAwMDA1NTc2OGUyMDIxZDAgUkRJOiAwMDAw MDAwMDAwMDAwMDA1Cj4gPiBbICAzNjkuNjI4NTY5XSBSQlA6IDAwMDA3ZjQzYzgxOTdmMDAgUjA4 OiAwMDAwMDAwMDAwMDAwMDExIFIwOTogMDAwMDdmNDNjODE5ODcwMAo+ID4gWyAgMzY5LjYzMDIw OF0gUjEwOiAwMDAwMDAwMDAwMDAwMDAwIFIxMTogMDAwMDAwMDAwMDAwMDI0NiBSMTI6IDAwMDA3 ZmZmODQ1ZTZhZmUKPiA+IFsgIDM2OS42MzIyNDBdIFIxMzogMDAwMDdmZmY4NDVlNmFmZiBSMTQ6 IDAwMDA3ZjQzYzgxOTdmYzAgUjE1OiAwMDAwN2Y0M2M4MTk4NzAwCj4gPiAKPiA+IFRoaXMgcGF0 Y2ggbW92ZXMgdGhlIHNrYl9yZWN2X2RhdGFncmFtKCkgYmVmb3JlIGxvY2tfc29jaygpIGluIG9y ZGVyIHRoYXQKPiA+IG90aGVyIGZ1bmN0aW9ucyB0aGF0IG5lZWQgbG9ja19zb2NrIGNvdWxkIGJl IGV4ZWN1dGVkLiBXaGF0YHMgbW9yZSwgd2UKPiA+IGFkZCBza2JfZnJlZV9kYXRhZ3JhbSgpIGJl Zm9yZSBnb3RvIG91dCBpbiBvcmRlciB0byBtaXRpZ2F0ZSBtZW1vcnkgbGVhay4KPiA+IAo+ID4g U3VnZ2VzdGVkLWJ5OiBUaG9tYXMgT3N0ZXJyaWVkIDx0aG9tYXNAb3N0ZXJyaWVkLmRlPgo+ID4g U2lnbmVkLW9mZi1ieTogRHVvbWluZyBaaG91IDxkdW9taW5nQHpqdS5lZHUuY24+Cj4gPiBSZXBv cnRlZC1ieTogVGhvbWFzIEhhYmV0cyA8dGhvbWFzQEBoYWJldHMuc2U+Cj4gPiAtLS0KPiA+IENo YW5nZXMgaW4gdjM6Cj4gPiAgIC0gQWRkIHNrYl9mcmVlX2RhdGFncmFtKCkgYmVmb3JlIGdvdG8g b3V0IGluIG9yZGVyIHRvIG1pdGlnYXRlIG1lbW9yeSBsZWFrLgo+ID4gCj4gPiAgbmV0L2F4MjUv YWZfYXgyNS5jIHwgMTIgKysrKysrKy0tLS0tCj4gPiAgMSBmaWxlIGNoYW5nZWQsIDcgaW5zZXJ0 aW9ucygrKSwgNSBkZWxldGlvbnMoLSkKPiA+IAo+ID4gZGlmZiAtLWdpdCBhL25ldC9heDI1L2Fm X2F4MjUuYyBiL25ldC9heDI1L2FmX2F4MjUuYwo+ID4gaW5kZXggOTUzOTNiYjI3NjAuLjYyYWE1 OTkzMDkzIDEwMDY0NAo+ID4gLS0tIGEvbmV0L2F4MjUvYWZfYXgyNS5jCj4gPiArKysgYi9uZXQv YXgyNS9hZl9heDI1LmMKPiA+IEBAIC0xNjY1LDYgKzE2NjUsMTEgQEAgc3RhdGljIGludCBheDI1 X3JlY3Ztc2coc3RydWN0IHNvY2tldCAqc29jaywgc3RydWN0IG1zZ2hkciAqbXNnLCBzaXplX3Qg c2l6ZSwKPiA+ICAJaW50IGNvcGllZDsKPiA+ICAJaW50IGVyciA9IDA7Cj4gPiAgCj4gPiArCS8q IE5vdyB3ZSBjYW4gdHJlYXQgYWxsIGFsaWtlICovCj4gPiArCXNrYiA9IHNrYl9yZWN2X2RhdGFn cmFtKHNrLCBmbGFncywgJmVycik7Cj4gPiArCWlmICghc2tiKQo+ID4gKwkJZ290byBkb25lOwo+ ID4gKwo+IAo+IE5vdGUgdGhhdCB0aGlzIGNhdXNlcyBhIGJlaGF2aW9yIGNoYW5nZTogYmVmb3Jl IHRoaXMgcGF0Y2gsIGNhbGxpbmcKPiByZWN2bXNnKCkgb24gdW5jb25uZWN0ZWQgc2VxcGFja2V0 IHNvY2tldHMgcmV0dXJuZWQgaW1tZWRpYXRlbGx5IHdpdGgKPiBhbiBlcnJvciAoZHVlIHRvIHRo ZSB0aGUgY2hlY2sgYmVsb3cpLCBub3cgaXQgYmxvY2tzLiAKPiAKPiBUaGUgY2hhbmdlIG1heSBj b25mdXNlICg9PSBicmVhaykgdXNlci1zcGFjZSBhcHBsaWNhdGlvbnMuIEkgdGhpbmsgaXQKPiB3 b3VsZCBiZSBiZXR0ZXIgcmVwbGFjaW5nIHNrYl9yZWN2X2RhdGFncmFtIHdpdGggYW4gb3Blbi1j b2RlZCB2YXJpYW50Cj4gb2YgaXQgcmVsZWFzaW5nIHRoZSBzb2NrZXQgbG9jayBiZWZvcmUgdGhl Cj4gX19za2Jfd2FpdF9mb3JfbW9yZV9wYWNrZXRzKCkgY2FsbCBhbmQgcmUtYWNxdWlyaW5nIGl0 IGFmdGVyIHN1Y2ggY2FsbC4KPiBTb21ld2hhdCBhbGlrZSBfX3VuaXhfZGdyYW1fcmVjdm1zZygp LgoKVGhhbmsgeW91IGZvciB5b3VyIHRpbWUgYW5kIHN1Z2dlc3Rpb25zIQpJIHRoaW5rIHRoZSBm b2xsb3dpbmcgbWV0aG9kIG1heSBzb2x2ZSB0aGUgcHJvYmxlbS4KCmRpZmYgLS1naXQgYS9uZXQv YXgyNS9hZl9heDI1LmMgYi9uZXQvYXgyNS9hZl9heDI1LmMKaW5kZXggOTUzOTNiYjI3NjAuLjUx YjQ0MWM4MzdjIDEwMDY0NAotLS0gYS9uZXQvYXgyNS9hZl9heDI1LmMKKysrIGIvbmV0L2F4MjUv YWZfYXgyNS5jCkBAIC0xNjc1LDggKzE2NzUsMTAgQEAgc3RhdGljIGludCBheDI1X3JlY3Ztc2co c3RydWN0IHNvY2tldCAqc29jaywgc3RydWN0IG1zZ2hkciAqbXNnLCBzaXplX3Qgc2l6ZSwKICAg ICAgICAgICAgICAgIGdvdG8gb3V0OwogICAgICAgIH0KCisgICAgICAgcmVsZWFzZV9zb2NrKHNr KTsKICAgICAgICAvKiBOb3cgd2UgY2FuIHRyZWF0IGFsbCBhbGlrZSAqLwogICAgICAgIHNrYiA9 IHNrYl9yZWN2X2RhdGFncmFtKHNrLCBmbGFncywgJmVycik7CisgICAgICAgbG9ja19zb2NrKHNr KTsKICAgICAgICBpZiAoc2tiID09IE5VTEwpCiAgICAgICAgICAgICAgICBnb3RvIG91dDsKClRo ZSBza2JfcmVjdl9kYXRhZ3JhbSgpIGlzIGZyZWUgb2YgcmFjZSBjb25kaXRpb25zIGFuZCBjb3Vs ZCBiZSByZS1lbnRyYW50LgpTbyBjYWxsaW5nIHNrYl9yZWN2X2RhdGFncmFtKCkgd2l0aG91dCB0 aGUgcHJvdGVjdGlvbiBvZiBsb2NrX3NvY2soKSBpcyBvay4KCldoYXQncyBtb3JlLCByZWxlYXNp bmcgdGhlIGxvY2tfc29jaygpIGJlZm9yZSBza2JfcmVjdl9kYXRhZ3JhbSgpIHdpbGwgbm90CmNh dXNlIFVBRiBidWdzLiBCZWNhdXNlIHRoZSBzb2NrIHdpbGwgbm90IGJlIGRlYWxsb2NhdGVkIHVu bGVzcyB3ZSBjYWxsCmF4MjVfcmVsZWFzZSgpLCBidXQgYXgyNV9yZWxlYXNlKCkgYW5kIGF4MjVf cmVjdm1zZygpIGNvdWxkIG5vdCBydW4gaW4gcGFyYWxsZWwuCgpBbHRob3VnaCB0aGUgInNrLT5z a19zdGF0ZSIgbWF5IGJlIGNoYW5nZWQgZHVlIHRvIHRoZSByZWxlYXNlIG9mIGxvY2tfc29jaygp LAppdCB3aWxsIG5vdCBpbmZsdWVuY2UgdGhlIGZvbGxvd2luZyBvcGVyYXRpb25zIGluIGF4MjVf cmVjdm1zZygpLgoKPiBJbiBhbnkgY2FzZSB0aGlzIGxhY2tzIGEgJ0ZpeGVzJyBwb2ludGluZyB0 byB0aGUgY29tbWl0IGludHJvZHVjaW5nIHRoZQo+IGlzc3VlIGFkZHJlc3NlZCBoZXJlLgoKVGhl IGNvbW1pdCB0aGF0IG5lZWQgdG8gYmUgZml4ZWQgaXMgYmVsb3c6CkZpeGVzOiA0MGQwYTkyM2Y1 NWEgKCJJbXBsZW1lbnQgbG9ja2luZyBvZiBpbnRlcm5hbCBkYXRhIGZvciBORVQvUk9NIGFuZCBS T1NFLiAiKQppbiBsaW51eC0yLjYuMTItcmMyLgoKQmVzdCByZWdhcmRzLApEdW9taW5nIFpob3U=