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 B9319C19F2B for ; Wed, 27 Jul 2022 16:43:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240017AbiG0Qnd (ORCPT ); Wed, 27 Jul 2022 12:43:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59184 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239758AbiG0QnO (ORCPT ); Wed, 27 Jul 2022 12:43:14 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8EEAE501A9; Wed, 27 Jul 2022 09:30:18 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C513561A09; Wed, 27 Jul 2022 16:30:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A57CBC433D7; Wed, 27 Jul 2022 16:30:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1658939415; bh=OUyJl/ofS2R449IpCtlkGA3fwfuxpMJvO0sO5mKjdLw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=b9zCi7rMpq6PrYMnvD1+M/T+QwWLVEysWobJzNDv8OaS1vuVFe7vphA2KgSvdDH3Q aOvpq1/EK2vWNEvwBGJsuR5lhaHuq26Knc6i9OAlqEmlcUbrkCJ17d+dPFcHd6yJ45 +d4b2x/dby+MtJ/RcU3e5c11AakXOILfV5yEOSgM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Will Deacon , Ard Biesheuvel , Kees Cook , Hanjun Guo , Ard Biesheuvel , Elena Reshetova , Linus Torvalds , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Sasha Levin Subject: [PATCH 5.4 62/87] locking/refcount: Remove unused refcount_*_checked() variants Date: Wed, 27 Jul 2022 18:10:55 +0200 Message-Id: <20220727161011.561064175@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220727161008.993711844@linuxfoundation.org> References: <20220727161008.993711844@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Will Deacon [ Upstream commit 7221762c48c6bbbcc6cc51d8b803c06930215e34 ] The full-fat refcount implementation is exposed via a set of functions suffixed with "_checked()", the idea being that code can choose to use the more expensive, yet more secure implementation on a case-by-case basis. In reality, this hasn't happened, so with a grand total of zero users, let's remove the checked variants for now by simply dropping the suffix and predicating the out-of-line functions on CONFIG_REFCOUNT_FULL=y. Signed-off-by: Will Deacon Reviewed-by: Ard Biesheuvel Reviewed-by: Kees Cook Tested-by: Hanjun Guo Cc: Ard Biesheuvel Cc: Elena Reshetova Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: https://lkml.kernel.org/r/20191121115902.2551-4-will@kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- include/linux/refcount.h | 25 ++++++------------- lib/refcount.c | 54 +++++++++++++++++++++------------------- 2 files changed, 36 insertions(+), 43 deletions(-) diff --git a/include/linux/refcount.h b/include/linux/refcount.h index 89066a1471dd..edd505d1a23b 100644 --- a/include/linux/refcount.h +++ b/include/linux/refcount.h @@ -44,32 +44,21 @@ static inline unsigned int refcount_read(const refcount_t *r) return atomic_read(&r->refs); } -extern __must_check bool refcount_add_not_zero_checked(int i, refcount_t *r); -extern void refcount_add_checked(int i, refcount_t *r); - -extern __must_check bool refcount_inc_not_zero_checked(refcount_t *r); -extern void refcount_inc_checked(refcount_t *r); - -extern __must_check bool refcount_sub_and_test_checked(int i, refcount_t *r); - -extern __must_check bool refcount_dec_and_test_checked(refcount_t *r); -extern void refcount_dec_checked(refcount_t *r); - #ifdef CONFIG_REFCOUNT_FULL #define REFCOUNT_MAX (UINT_MAX - 1) #define REFCOUNT_SATURATED UINT_MAX -#define refcount_add_not_zero refcount_add_not_zero_checked -#define refcount_add refcount_add_checked +extern __must_check bool refcount_add_not_zero(int i, refcount_t *r); +extern void refcount_add(int i, refcount_t *r); -#define refcount_inc_not_zero refcount_inc_not_zero_checked -#define refcount_inc refcount_inc_checked +extern __must_check bool refcount_inc_not_zero(refcount_t *r); +extern void refcount_inc(refcount_t *r); -#define refcount_sub_and_test refcount_sub_and_test_checked +extern __must_check bool refcount_sub_and_test(int i, refcount_t *r); -#define refcount_dec_and_test refcount_dec_and_test_checked -#define refcount_dec refcount_dec_checked +extern __must_check bool refcount_dec_and_test(refcount_t *r); +extern void refcount_dec(refcount_t *r); #else diff --git a/lib/refcount.c b/lib/refcount.c index 719b0bc42ab1..a2f670998cee 100644 --- a/lib/refcount.c +++ b/lib/refcount.c @@ -43,8 +43,10 @@ #include #include +#ifdef CONFIG_REFCOUNT_FULL + /** - * refcount_add_not_zero_checked - add a value to a refcount unless it is 0 + * refcount_add_not_zero - add a value to a refcount unless it is 0 * @i: the value to add to the refcount * @r: the refcount * @@ -61,7 +63,7 @@ * * Return: false if the passed refcount is 0, true otherwise */ -bool refcount_add_not_zero_checked(int i, refcount_t *r) +bool refcount_add_not_zero(int i, refcount_t *r) { unsigned int new, val = atomic_read(&r->refs); @@ -83,10 +85,10 @@ bool refcount_add_not_zero_checked(int i, refcount_t *r) return true; } -EXPORT_SYMBOL(refcount_add_not_zero_checked); +EXPORT_SYMBOL(refcount_add_not_zero); /** - * refcount_add_checked - add a value to a refcount + * refcount_add - add a value to a refcount * @i: the value to add to the refcount * @r: the refcount * @@ -101,14 +103,14 @@ EXPORT_SYMBOL(refcount_add_not_zero_checked); * cases, refcount_inc(), or one of its variants, should instead be used to * increment a reference count. */ -void refcount_add_checked(int i, refcount_t *r) +void refcount_add(int i, refcount_t *r) { - WARN_ONCE(!refcount_add_not_zero_checked(i, r), "refcount_t: addition on 0; use-after-free.\n"); + WARN_ONCE(!refcount_add_not_zero(i, r), "refcount_t: addition on 0; use-after-free.\n"); } -EXPORT_SYMBOL(refcount_add_checked); +EXPORT_SYMBOL(refcount_add); /** - * refcount_inc_not_zero_checked - increment a refcount unless it is 0 + * refcount_inc_not_zero - increment a refcount unless it is 0 * @r: the refcount to increment * * Similar to atomic_inc_not_zero(), but will saturate at REFCOUNT_SATURATED @@ -120,7 +122,7 @@ EXPORT_SYMBOL(refcount_add_checked); * * Return: true if the increment was successful, false otherwise */ -bool refcount_inc_not_zero_checked(refcount_t *r) +bool refcount_inc_not_zero(refcount_t *r) { unsigned int new, val = atomic_read(&r->refs); @@ -140,10 +142,10 @@ bool refcount_inc_not_zero_checked(refcount_t *r) return true; } -EXPORT_SYMBOL(refcount_inc_not_zero_checked); +EXPORT_SYMBOL(refcount_inc_not_zero); /** - * refcount_inc_checked - increment a refcount + * refcount_inc - increment a refcount * @r: the refcount to increment * * Similar to atomic_inc(), but will saturate at REFCOUNT_SATURATED and WARN. @@ -154,14 +156,14 @@ EXPORT_SYMBOL(refcount_inc_not_zero_checked); * Will WARN if the refcount is 0, as this represents a possible use-after-free * condition. */ -void refcount_inc_checked(refcount_t *r) +void refcount_inc(refcount_t *r) { - WARN_ONCE(!refcount_inc_not_zero_checked(r), "refcount_t: increment on 0; use-after-free.\n"); + WARN_ONCE(!refcount_inc_not_zero(r), "refcount_t: increment on 0; use-after-free.\n"); } -EXPORT_SYMBOL(refcount_inc_checked); +EXPORT_SYMBOL(refcount_inc); /** - * refcount_sub_and_test_checked - subtract from a refcount and test if it is 0 + * refcount_sub_and_test - subtract from a refcount and test if it is 0 * @i: amount to subtract from the refcount * @r: the refcount * @@ -180,7 +182,7 @@ EXPORT_SYMBOL(refcount_inc_checked); * * Return: true if the resulting refcount is 0, false otherwise */ -bool refcount_sub_and_test_checked(int i, refcount_t *r) +bool refcount_sub_and_test(int i, refcount_t *r) { unsigned int new, val = atomic_read(&r->refs); @@ -203,10 +205,10 @@ bool refcount_sub_and_test_checked(int i, refcount_t *r) return false; } -EXPORT_SYMBOL(refcount_sub_and_test_checked); +EXPORT_SYMBOL(refcount_sub_and_test); /** - * refcount_dec_and_test_checked - decrement a refcount and test if it is 0 + * refcount_dec_and_test - decrement a refcount and test if it is 0 * @r: the refcount * * Similar to atomic_dec_and_test(), it will WARN on underflow and fail to @@ -218,14 +220,14 @@ EXPORT_SYMBOL(refcount_sub_and_test_checked); * * Return: true if the resulting refcount is 0, false otherwise */ -bool refcount_dec_and_test_checked(refcount_t *r) +bool refcount_dec_and_test(refcount_t *r) { - return refcount_sub_and_test_checked(1, r); + return refcount_sub_and_test(1, r); } -EXPORT_SYMBOL(refcount_dec_and_test_checked); +EXPORT_SYMBOL(refcount_dec_and_test); /** - * refcount_dec_checked - decrement a refcount + * refcount_dec - decrement a refcount * @r: the refcount * * Similar to atomic_dec(), it will WARN on underflow and fail to decrement @@ -234,11 +236,13 @@ EXPORT_SYMBOL(refcount_dec_and_test_checked); * Provides release memory ordering, such that prior loads and stores are done * before. */ -void refcount_dec_checked(refcount_t *r) +void refcount_dec(refcount_t *r) { - WARN_ONCE(refcount_dec_and_test_checked(r), "refcount_t: decrement hit 0; leaking memory.\n"); + WARN_ONCE(refcount_dec_and_test(r), "refcount_t: decrement hit 0; leaking memory.\n"); } -EXPORT_SYMBOL(refcount_dec_checked); +EXPORT_SYMBOL(refcount_dec); + +#endif /* CONFIG_REFCOUNT_FULL */ /** * refcount_dec_if_one - decrement a refcount if it is 1 -- 2.35.1