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 91B8BC433F5 for ; Sun, 15 May 2022 20:01:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238561AbiEOUBd (ORCPT ); Sun, 15 May 2022 16:01:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45962 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233813AbiEOUB0 (ORCPT ); Sun, 15 May 2022 16:01:26 -0400 Received: from mail-lf1-x12d.google.com (mail-lf1-x12d.google.com [IPv6:2a00:1450:4864:20::12d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6CA84115E for ; Sun, 15 May 2022 13:01:25 -0700 (PDT) Received: by mail-lf1-x12d.google.com with SMTP id u23so22653752lfc.1 for ; Sun, 15 May 2022 13:01:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=KXD8XuC6lGBVzyqbnaNhW/9Jgk1+Ek/2FLjcPeEVLJA=; b=KH5+P8Xoi5HgyXB7Y+7GMpsUsGVV6RDdEUampVl6jnhZxuvpLkdrzHHFIKi7VLgOQV UHr4MVDLXs0NOxd0t6wApmnjRo/n5HKhEWi5ibYjjxhZk6DICECGZBfkulbgqbHT+ooC 0zuvcX3HGyZnBWz3TWGwWAPPyT5qhoIWXKS4z0HltbTR+DvoYj2xi2DLU6uHAUffPtzN gZ0vPGsW3tKgS22I72Agpv/XHZeE5sZjxnkjZMMozRBvYgZZn0wGBdqXoqzBA1Q7GthI SPXY4w4bg6l4OX1pH7GxfPPkob/iAgAqYr4U9KF+RCLnZ1dbUoHkHP+y3gmPSyTainix vNlw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=KXD8XuC6lGBVzyqbnaNhW/9Jgk1+Ek/2FLjcPeEVLJA=; b=rsfpPh087jIm0aQ0UHR18DwARtzX5hFi5v4Eo0aaOlNTUvNJqsBAvK8H05/bemhOKv gE7L62Iu70m8q95v7WfR1v5xjo3qooydT0RO1szgI06psWtp80bmx8X8O8gXckVpfA8R 7XtDZanPWvEd6iueCRmTwr+E/yMHxx8NgAnb85KZPi3g0brsk2I59/Fhm8zWY41PxCvk XRhlV7DIIXa/9xfatPQiGdmPe1vHMPXJ5u5kUNa0jOmoqDQK8WJSwMPrNcprDo00dNc3 seE2cXwgIR1ldA7Ervv0TCd9XW5RRyebIvKL0h8oUEPj1kTq1eyrvw07JFgNrp1dIqdN JsPQ== X-Gm-Message-State: AOAM530C+6IAeAa37Gq1fO/UhIjr49kZvjyfES2Vgo/yVheY6JlmW5fw qKRZ7NNvneYGseDIUDFkKmTSSM7kH4Q= X-Google-Smtp-Source: ABdhPJyVp1bL9PhOCNDmLztDmC0ZfC5UKbkq60mzC+SVyNyN8IH8vEaPFuRcGyaj2fVkg6u9xESa5Q== X-Received: by 2002:a19:ca02:0:b0:474:854:ed5c with SMTP id a2-20020a19ca02000000b004740854ed5cmr10574246lfg.643.1652644883805; Sun, 15 May 2022 13:01:23 -0700 (PDT) Received: from localhost ([178.170.168.3]) by smtp.gmail.com with ESMTPSA id j20-20020a2e8014000000b0024f3d1dae96sm1295878ljg.30.2022.05.15.13.01.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 15 May 2022 13:01:23 -0700 (PDT) From: Maxim Zhukov X-Google-Original-From: Maxim Zhukov To: chi.minghao@zte.com.cn, varad.gautam@suse.com, arnd@arndb.de Cc: akpm@linux-foundation.org, shakeelb@google.com, vasily.averin@linux.dev, manfred@colorfullife.com, dbueso@suse.de, linux-kernel@vger.kernel.org, Maxim Zhukov Subject: [RFC PATCH 1/1] ipc, sem: fix backward compatibility with x86-32 kernels Date: Sun, 15 May 2022 23:01:03 +0300 Message-Id: <20220515200103.1408370-2-mussitantesmortem@gmail.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220515200103.1408370-1-mussitantesmortem@gmail.com> References: <20220515200103.1408370-1-mussitantesmortem@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since with commit 275f22148e87 ("ipc: rename old-style shmctl/semctl/msgctl syscalls") we have changed behavior: ksys_semctl lost parse ipc version (ipc_parse_version), because the new syscall works with IPC_64 only, but the parse function has some side effect - it removes IPC_64 bit from `cmd`. Some libc forced sends IPC_64 bit in semctl syscall[1][2][3], this leads to a bug - X86-32 kernel does not have compat headers and does not correctly parse received command (cmd) from semctl syscall: cmd have actual command and IPC_64 bit, thus throw EINVAL error in ksys_semctl This commit forcibly removes IPC_64 bit from the cmd for restore backward compatibility. [1]: https://elixir.bootlin.com/uclibc-ng/v1.0.40/source/libc/misc/sysvipc/sem.c#L58 [2]: https://elixir.bootlin.com/musl/v1.2.3/source/src/ipc/semctl.c#L48 -> https://elixir.bootlin.com/musl/v1.2.3/source/src/ipc/ipc.h#L22 [3]: https://elixir.bootlin.com/glibc/glibc-2.35/source/sysdeps/unix/sysv/linux/semctl.c#L124 Signed-off-by: Maxim Zhukov --- ipc/sem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ipc/sem.c b/ipc/sem.c index 0dbdb98fdf2d..824244170000 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -1706,7 +1706,7 @@ static long ksys_semctl(int semid, int semnum, int cmd, unsigned long arg, int v SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg) { - return ksys_semctl(semid, semnum, cmd, arg, IPC_64); + return ksys_semctl(semid, semnum, cmd & (~IPC_64), arg, IPC_64); } #ifdef CONFIG_ARCH_WANT_IPC_PARSE_VERSION -- 2.36.1