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Miller" , Andrew Zaborowski CC: , , , References: <20240910111806.65945-1-r.smirnov@omp.ru> <84d6b0fa-4948-fe58-c766-17f87c2a2dba@omp.ru> From: Sergey Shtylyov Organization: Open Mobile Platform Message-ID: <85607ea7-a42a-1c7b-0722-e4b63a814385@omp.ru> Date: Wed, 11 Sep 2024 17:45:49 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 Precedence: bulk X-Mailing-List: linux-crypto@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: msexch01.omp.ru (10.188.4.12) To msexch01.omp.ru (10.188.4.12) X-KSE-ServerInfo: msexch01.omp.ru, 9 X-KSE-AntiSpam-Interceptor-Info: scan successful X-KSE-AntiSpam-Version: 6.1.1, Database issued on: 09/11/2024 14:26:16 X-KSE-AntiSpam-Status: KAS_STATUS_NOT_DETECTED X-KSE-AntiSpam-Method: none X-KSE-AntiSpam-Rate: 59 X-KSE-AntiSpam-Info: Lua profiles 187687 [Sep 11 2024] X-KSE-AntiSpam-Info: Version: 6.1.1.5 X-KSE-AntiSpam-Info: Envelope from: s.shtylyov@omp.ru X-KSE-AntiSpam-Info: LuaCore: 32 0.3.32 766319f57b3d5e49f2c79a76e7d7087b621090df X-KSE-AntiSpam-Info: {rep_avail} X-KSE-AntiSpam-Info: {Tracking_from_domain_doesnt_match_to} X-KSE-AntiSpam-Info: {relay has no DNS name} X-KSE-AntiSpam-Info: {SMTP from is not routable} X-KSE-AntiSpam-Info: {Found in DNSBL: 31.173.80.211 in (user) b.barracudacentral.org} X-KSE-AntiSpam-Info: omp.ru:7.1.1;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;127.0.0.199:7.1.2 X-KSE-AntiSpam-Info: FromAlignment: s X-KSE-AntiSpam-Info: ApMailHostAddress: 31.173.80.211 X-KSE-AntiSpam-Info: {DNS response errors} X-KSE-AntiSpam-Info: Rate: 59 X-KSE-AntiSpam-Info: Status: not_detected X-KSE-AntiSpam-Info: Method: none X-KSE-AntiSpam-Info: Auth:dmarc=temperror header.from=omp.ru;spf=temperror smtp.mailfrom=omp.ru;dkim=none X-KSE-Antiphishing-Info: Clean X-KSE-Antiphishing-ScanningType: Heuristic X-KSE-Antiphishing-Method: None X-KSE-Antiphishing-Bases: 09/11/2024 14:29:00 X-KSE-Antivirus-Interceptor-Info: scan successful X-KSE-Antivirus-Info: Clean, bases: 9/11/2024 1:02:00 PM X-KSE-Attachment-Filter-Triggered-Rules: Clean X-KSE-Attachment-Filter-Triggered-Filters: Clean X-KSE-BulkMessagesFiltering-Scan-Result: InTheLimit On 9/11/24 4:19 PM, Jarkko Sakkinen wrote: [...] >>>>> In find_asymmetric_key(), if all NULLs are passed in id_{0,1,2} parameters >>>>> the kernel will first emit WARN and then have an oops because id_2 gets >>>>> dereferenced anyway. >>>>> >>>>> Found by Linux Verification Center (linuxtesting.org) with Svace static >>>>> analysis tool. >>>> >>>> Weird, I recall that I've either sent a patch to address the same site >>>> OR have commented a patch with similar reasoning. Well, it does not >>>> matter, I think it this makes sense to me. >>>> >>>> You could further add to the motivation that given the panic_on_warn >>>> kernel command-line parameter, it is for the best limit the scope and >>>> use of the WARN-macro. >>> >>> I don't understand what you mean -- this version of the patch keeps >>> the WARN_ON() call, it just moves that call, so that the duplicate id_{0,1,2} >>> checks are avoided... >> >> I overlooked the code change (my bad sorry). Here's a better version of >> the first paragraph: >> >> "find_asymmetric_keys() has nullity checks of id_0 and id_1 but ignores >> validation for id_2. Check nullity also for id_2." >> >> Yep, and it changes no situation with WARN_ON() macro for better or >> worse. It would logically separate issue to discuss and address so >> as far as I'm concerned, with this clarification I think the change >> makes sense to me. > > Actually explicitly stating that call paths leading to WARN_ON() > invocation are intact by the commit (as a reminder for future). OK... Do you still think the Fixes tag should be dropped (and thus the Reported-by tag would become unnecessary?)? > BR, Jarkko MBR, Sergey