From nobody Sat Oct 4 00:31:18 2025 Received: from pegase2.c-s.fr (pegase2.c-s.fr [93.17.235.10]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4FC6A2F068E; Fri, 22 Aug 2025 10:21:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=93.17.235.10 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755858074; cv=none; b=lD7XtHQlA6eznS/DbEn2pau0W113IrnwWtmrxB+2HzdgBrgV3fRFkon6uvpYol6x9p+3W8DeUM4h7FZ+6qAcZWCUm6PJpzL17t28+3+jdscCaw3fskKFrd3Y1L5Hs0qWOdte6XiyO+h/vJw5lF0X4rGBnm5v1mBriG9DYM0fQDI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755858074; c=relaxed/simple; bh=f9F9/cRuytydLUtTkyZlSioNNHJr4smVC+NwESq3LiE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GY2gpyl6/1QWwbdG5nC88GVpGUAwOjflUdiT+rIjGFC7igbGw8c3zE46RtFTh4bclIUV5LPoajj829FOi4RYwAyT9DDCREkh6tgnloy+5rBFCUqv/Lgzlh8j9D3b+JHnYLVKnvy46JHd6vBfw/lndS/lWO8VAB01SVH7ZlMZIvo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=csgroup.eu; spf=pass smtp.mailfrom=csgroup.eu; arc=none smtp.client-ip=93.17.235.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=csgroup.eu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=csgroup.eu Received: from localhost (mailhub4.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4c7bGt1fvqz9sSd; Fri, 22 Aug 2025 11:58:14 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase2.c-s.fr ([172.26.127.65]) by localhost (pegase2.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id nA9tiptLvbS4; Fri, 22 Aug 2025 11:58:14 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase2.c-s.fr (Postfix) with ESMTP id 4c7bGt0fxTz9sSc; Fri, 22 Aug 2025 11:58:14 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id F2A058B781; Fri, 22 Aug 2025 11:58:13 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id xGJtbDV9gyfJ; Fri, 22 Aug 2025 11:58:13 +0200 (CEST) Received: from PO20335.idsi0.si.c-s.fr (unknown [192.168.235.99]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 00A1D8B775; Fri, 22 Aug 2025 11:58:12 +0200 (CEST) From: Christophe Leroy To: Michael Ellerman , Nicholas Piggin , Madhavan Srinivasan , Alexander Viro , Christian Brauner , Jan Kara , Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Darren Hart , Davidlohr Bueso , "Andre Almeida" , Andrew Morton , David Laight , Dave Hansen , Linus Torvalds , Daniel Borkmann Cc: Christophe Leroy , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org Subject: [PATCH v2 07/10] powerpc/uaccess: Refactor user_{read/write/}_access_begin() Date: Fri, 22 Aug 2025 11:58:03 +0200 Message-ID: X-Mailer: git-send-email 2.49.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1755856679; l=3531; i=christophe.leroy@csgroup.eu; s=20211009; h=from:subject:message-id; bh=f9F9/cRuytydLUtTkyZlSioNNHJr4smVC+NwESq3LiE=; b=iGg6YdGAsWyUK0iNyg6FWIwUKR9y2x0CwCJ+wXEjuvZEm5CU7Pic2aw23YM8P5L+Yc1baQWjs 9Okn+6PeCsDCvFYf0Q9gOtBhSQ0ERuHaxTeQbnXZTGDNJug9EN2Om79 X-Developer-Key: i=christophe.leroy@csgroup.eu; a=ed25519; pk=HIzTzUj91asvincQGOFx6+ZF5AoUuP9GdOtQChs7Mm0= Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" user_read_access_begin() and user_write_access_begin() and user_access_begin() are now very similar. Create a common __user_access_begin() that take direction as parameter. In order to avoid a warning with the conditional call of barrier_nospec() which is sometimes an empty macro, change it to a do {} while (0). Signed-off-by: Christophe Leroy --- v2: New --- arch/powerpc/include/asm/barrier.h | 2 +- arch/powerpc/include/asm/uaccess.h | 46 +++++++++--------------------- 2 files changed, 14 insertions(+), 34 deletions(-) diff --git a/arch/powerpc/include/asm/barrier.h b/arch/powerpc/include/asm/= barrier.h index b95b666f0374..7acbf27cac6c 100644 --- a/arch/powerpc/include/asm/barrier.h +++ b/arch/powerpc/include/asm/barrier.h @@ -102,7 +102,7 @@ do { \ =20 #else /* !CONFIG_PPC_BARRIER_NOSPEC */ #define barrier_nospec_asm -#define barrier_nospec() +#define barrier_nospec() do {} while (0) #endif /* CONFIG_PPC_BARRIER_NOSPEC */ =20 /* diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/= uaccess.h index 698996f34891..49254f7d9069 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -410,50 +410,30 @@ copy_mc_to_user(void __user *to, const void *from, un= signed long n) extern long __copy_from_user_flushcache(void *dst, const void __user *src, unsigned size); =20 -static __must_check __always_inline bool user_access_begin(const void __us= er *ptr, size_t len) +static __must_check __always_inline bool __user_access_begin(const void __= user *ptr, size_t len, + unsigned long dir) { if (unlikely(!access_ok(ptr, len))) return false; =20 might_fault(); =20 - barrier_nospec(); - allow_read_write_user((void __user *)ptr, ptr, len); + if (dir & KUAP_READ) + barrier_nospec(); + allow_user_access((void __user *)ptr, dir); return true; } -#define user_access_begin user_access_begin -#define user_access_end prevent_current_access_user -#define user_access_save prevent_user_access_return -#define user_access_restore restore_user_access =20 -static __must_check __always_inline bool -user_read_access_begin(const void __user *ptr, size_t len) -{ - if (unlikely(!access_ok(ptr, len))) - return false; +#define user_access_begin(p, l) __user_access_begin(p, l, KUAP_READ_WRITE) +#define user_read_access_begin(p, l) __user_access_begin(p, l, KUAP_READ) +#define user_write_access_begin(p, l) __user_access_begin(p, l, KUAP_WRITE) =20 - might_fault(); - - barrier_nospec(); - allow_read_from_user(ptr, len); - return true; -} -#define user_read_access_begin user_read_access_begin -#define user_read_access_end prevent_current_read_from_user +#define user_access_end() prevent_user_access(KUAP_READ_WRITE) +#define user_read_access_end() prevent_user_access(KUAP_READ) +#define user_write_access_end() prevent_user_access(KUAP_WRITE) =20 -static __must_check __always_inline bool -user_write_access_begin(const void __user *ptr, size_t len) -{ - if (unlikely(!access_ok(ptr, len))) - return false; - - might_fault(); - - allow_write_to_user((void __user *)ptr, len); - return true; -} -#define user_write_access_begin user_write_access_begin -#define user_write_access_end prevent_current_write_to_user +#define user_access_save prevent_user_access_return +#define user_access_restore restore_user_access =20 #define unsafe_get_user(x, p, e) do { \ __long_type(*(p)) __gu_val; \ --=20 2.49.0