From patchwork Tue Oct 18 08:22:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 4007 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:4ac7:0:0:0:0:0 with SMTP id y7csp1839982wrs; Tue, 18 Oct 2022 01:30:41 -0700 (PDT) X-Google-Smtp-Source: AMsMyM7vM+Gu6LAX8f/1WHhaaK5wgNtQBYGnYGyursmmhlZkjRDakCf6aMz6pizKEDx8hMsEDUdT X-Received: by 2002:a17:907:7f02:b0:73d:dffa:57b3 with SMTP id qf2-20020a1709077f0200b0073ddffa57b3mr1509873ejc.19.1666081841528; Tue, 18 Oct 2022 01:30:41 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1666081841; cv=none; d=google.com; s=arc-20160816; b=Q8nf9gerh8gM+/l5qxVaUEjBTkVKZBiJW7KNQrhFxxdJxPt/5PwAjzp1IOrf566Gw8 jnyPkI9lv4htdIM+stM0tVZM+wLSzmS57utjTaEiENAGDi/m17wKWX4KBvyWQFjVMOQk CQ/bntcL0p731PkOxbutTe4HThk8PNb/fy1g54N7tSqn7pexfS/Pvzorqcn1GxwjZA7Q IDGZUIL14yAD0mC82Dn14MaImpnkb5V52rj5PmK/EJPqdB0u3Hc9pahjJKWaEKz7I1YQ uDmTqaWcL6k+H72TXzMwUqUCzODLKl+Mlo7TeL51ZRtRvFgcxRnkM8tVSPJDZWOqJiRZ DeCg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from:dkim-signature; bh=GnqNHNhYyLH9Wo68LD4x3bwQRhcMnm8gL4scZhF5muk=; b=SL/F2lhRsKU6AtHVgZUdHkRfoyVAyIiFglLlIPp0btuGOonxHJRU/cLRaAEoC/9q2k zchR79sPyFOJheEq5fPzgDXFWAnFqL2k7GRl3RwGH+rXmG0cGxMSt1OnM2Y13nzJ1EYv jzZGRodGviVcmJfMI3gYhmMf4MmRkB6XGRtHxUf6lPvpJ6dg0+213sHcA/Gzjw6ZAYZK FemuFZwWUcvPXfkt/cobz2oe3h8PEfJWXFs6qVFb/7Tr4D1JPqDcQAI/pJ69nKAHAldi K4JNOnvKo3iCCPHl7wC1dRKHdJEvhCCIgSxCigfDyYAiwa3J657OBciA/XSMGHn/GHGQ UKyA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=g+M0tP4F; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id p11-20020a50cd8b000000b00459a988ca2csi10477196edi.116.2022.10.18.01.30.15; Tue, 18 Oct 2022 01:30:41 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=g+M0tP4F; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230458AbiJRIWv (ORCPT + 99 others); Tue, 18 Oct 2022 04:22:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230409AbiJRIWp (ORCPT ); Tue, 18 Oct 2022 04:22:45 -0400 Received: from mail-pf1-x42a.google.com (mail-pf1-x42a.google.com [IPv6:2607:f8b0:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 31CB397D64 for ; Tue, 18 Oct 2022 01:22:45 -0700 (PDT) Received: by mail-pf1-x42a.google.com with SMTP id m6so13451722pfb.0 for ; Tue, 18 Oct 2022 01:22:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=GnqNHNhYyLH9Wo68LD4x3bwQRhcMnm8gL4scZhF5muk=; b=g+M0tP4FeC0OrEgQxOE3oJjv9pUB6oD9RgZ+XBPsA0B85VsOEiUZa6cSIgQOnwn/bl PMcN3F6LLRPoLDCxP3nuCJikCNGhdt00VAuMFuO3rxW1gs8KlSrBeB+vNyMB4cCCH/Gc kvdVgkwL8LfHNJuSEL7+LJTehFvWBdJr0abNA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=GnqNHNhYyLH9Wo68LD4x3bwQRhcMnm8gL4scZhF5muk=; b=KfYuf7l/I69MebWy1TxZx9GW6omz5oA6YyIB/Tgu0DWAiSnvEQ5jGQUPHGeAGoKlYq uYPuZdpcOqruwY3oEJAL4e9zv5zRZCsq4bwIFtkimLp2CyKkNIhU83dT/zp1oT1eMlgv UUGi9A2KBZLlDVGpeaaAYSj1HF7l0dxoegaTDQSk63tc3b8dZ54sf7pKUb7db1cMc7a1 zRBSWYTQZJGAHqQpO6oiO/GjYPC1vJc1C4zIM5OHPbUmSX9Ts4s6YfpOSzuatVIV038J JQqL2NzUeEnsXYmBtefO5ziJwRtzhPkP6ckZ20YSjIHReXYZel/plsRsJQn2UC/RqRXN Lpdg== X-Gm-Message-State: ACrzQf0hRd7PC2R3kEW3eLvF9XO4MFf9KulwjBaPhxj+ai5ms17p/u/5 yaEGl4616xamYnrIxoOV716pKg== X-Received: by 2002:a63:4283:0:b0:457:dced:8ba3 with SMTP id p125-20020a634283000000b00457dced8ba3mr1711359pga.220.1666081364707; Tue, 18 Oct 2022 01:22:44 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id m2-20020a170902db0200b0017d97d13b18sm8026045plx.65.2022.10.18.01.22.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Oct 2022 01:22:44 -0700 (PDT) From: Kees Cook To: linux-hardening@vger.kernel.org Cc: Kees Cook , Guenter Roeck , Andy Shevchenko , Paolo Abeni , Geert Uytterhoeven , linux-kernel@vger.kernel.org Subject: [PATCH] string: Add __alloc_size hint to kmemdup() Date: Tue, 18 Oct 2022 01:22:41 -0700 Message-Id: <20221018082232.never.213-kees@kernel.org> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1853; h=from:subject:message-id; bh=SgzbSvS/b5ZrTbA0wJ9E9tBFT9DRkYwk8ZJEQZFVEak=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBjTmJRV6GiRT0HuXsWsQSPL85x/s8fMsdifykSjHzh OlUuKfmJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCY05iUQAKCRCJcvTf3G3AJj8rD/ 9KYnzy5bqIwa32boPh44jUw+r1zKss52V+nzSaViIRwLNMVToZqpHJ2eZ7cIQKOwfMoHYAPiOhhFCE yUV8wPUrPSzXQSc6Y/4etatCvIVMl6/LpGjfjELhI5SOKGmfpMTI77z45BTRoZJFabztTn3aSt18hX AF6wjRN8M/oLYCX8lws5Jm1x/CwOnb8Y9yLaLaVRFpaloXmTNijmKNDioJ3qCyX9D/zvSQZ2o7TAi7 0jA+eem6Aq8EIFBeRb9axI7myTreYHszRjIFO+Z10WSLfh9MpvZ78HuK2WDTjbFr1iX/pPqGl+7Zc6 qCa+lJfFF7IjkI3mG7SYwUyVktGy5BqO61c/T2TS+V9XKORhBy4rmyA50/RMt1DfMW6ETiWuCMGp2u VdRwBsZ8qNwaq3nx/51bwQXEFc1U056LcUYBH25qctK872Y7LQVFzJ/WA4HmZmj1hlT8cqb57AVP/3 dIAQI5YZz6PKJpg97tjLaO5ccXGqXrNbSVck7v+h49vz+UUTQdtYUtCOUQ+Bze4KRdjJWqhpZI3r5N dLB9ifjVvhwjnAjuPJIWE6eKu1uC/lqjhZBxmCByUWw64JZGQKjx6LDf3HN+ZD7R//tYqoPM6Vnk9u FddwMhg6qb1FNSRb+45QtPu0FB+r4Fe7JhjpR+EPEYO1XheosCSb3ouIA/+w== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 X-Spam-Status: No, score=-2.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1747013432726708101?= X-GMAIL-MSGID: =?utf-8?q?1747013432726708101?= Add __alloc_size() hint to kmemdup() so the compiler can reason about the length of the returned buffer. Cc: Guenter Roeck Cc: Andy Shevchenko Cc: Paolo Abeni Cc: Geert Uytterhoeven Signed-off-by: Kees Cook --- include/linux/fortify-string.h | 3 ++- include/linux/string.h | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/include/linux/fortify-string.h b/include/linux/fortify-string.h index b166364ce3e0..aa1a50009632 100644 --- a/include/linux/fortify-string.h +++ b/include/linux/fortify-string.h @@ -661,7 +661,8 @@ __FORTIFY_INLINE void *memchr_inv(const void * const POS0 p, int c, size_t size) return __real_memchr_inv(p, c, size); } -extern void *__real_kmemdup(const void *src, size_t len, gfp_t gfp) __RENAME(kmemdup); +extern void *__real_kmemdup(const void *src, size_t len, gfp_t gfp) __RENAME(kmemdup) + __alloc_size(2); __FORTIFY_INLINE void *kmemdup(const void * const POS0 p, size_t size, gfp_t gfp) { size_t p_size = __struct_size(p); diff --git a/include/linux/string.h b/include/linux/string.h index cf7607b32102..af1d69e5610e 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -176,7 +176,7 @@ extern void kfree_const(const void *x); extern char *kstrdup(const char *s, gfp_t gfp) __malloc; extern const char *kstrdup_const(const char *s, gfp_t gfp); extern char *kstrndup(const char *s, size_t len, gfp_t gfp); -extern void *kmemdup(const void *src, size_t len, gfp_t gfp); +extern void *kmemdup(const void *src, size_t len, gfp_t gfp) __alloc_size(2); extern char *kmemdup_nul(const char *s, size_t len, gfp_t gfp); extern char **argv_split(gfp_t gfp, const char *str, int *argcp);