From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2CD5D2F1FE6; Mon, 27 Oct 2025 08:43:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761554632; cv=none; b=CB9iCDNLmDCOWdEo4VENf1Fe3uHAwktJGAWuttUku49ibm8pSeK/loNpxXKHgsseRMyMhqSS5xxs+Nu9Tgq7SWYu9sQJcvwvPX4q330Nqsa5v0XE/gkqszHCVTRF29G/eS/PAGv1rRD3LqY6PRRGFXcdFBtS+W9AOtaLcuPkubQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761554632; c=relaxed/simple; bh=kv2agbdsqIbzMLDcTPxxSBLHwg3H9gA4/g6IZ/c2ULk=; h=Message-ID:From:To:Cc:Subject:References:MIME-Version: Content-Type:Date; b=CWDBlntoyAJ8M0snCfKdCbnzxlRxQ48WM+CvnF/73OgRNo5pJUbWgqfIDwztp9n0qCwFTacA5ak1zc4/B4rbAqL4DoPPyhRhxhJzusFbWQRoHr1ESXfFG7Xnrh0k1LkS5Nun3gOvswu84+9WJ9n/6qH3MJFUHxnY1bcLBL6Fzts= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Shun7IjV; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=CjAAJqTB; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Shun7IjV"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="CjAAJqTB" Message-ID: <20251027083745.356628509@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1761554629; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=DNQHcterXWXQuFWR5KPGbkzD3Sh/vJk9lLVEwO1xPSA=; b=Shun7IjVfYUPlEkByDviiP8FOOaPtcom7r3qT0QBgoYlkb5vVwr+bQ4W4TGvFBSI3ZaZZR +20dugYVw1XjPXkDP5YySKtN01v9L3UhhgPMAozbd9iTr5u/pfXPwlvPDEoj2eN9Rj3tdS FgNcCCZMo7m/ESx0d2/P7CcfOtUZByEi1Q5vdVk6Rm9cKUF0/gPodfvQYfARbcL06zSFj8 EJcAJO5BlCn5G3xT2nW85AxFwE6WyRsbFUVB1x4KZYyo7Y3JTTFgskCCG72B3F2UERG1en UpXuHrFLcxh5qeAKwe+AtutqsB/hJ93fVNcggB2CsGQvpnMSloAE9dGSvojtdw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1761554629; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=DNQHcterXWXQuFWR5KPGbkzD3Sh/vJk9lLVEwO1xPSA=; b=CjAAJqTBR4AiPBtCOu7ZrMjj2ByjpD9kOdxzU0+8Jcl/6N+Mh+z+AJN5HxvT1ZXUhXLEd0 lCdJ913xubPYmqBA== From: Thomas Gleixner To: LKML Cc: Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , linuxppc-dev@lists.ozlabs.org, kernel test robot , Russell King , linux-arm-kernel@lists.infradead.org, Linus Torvalds , x86@kernel.org, Paul Walmsley , Palmer Dabbelt , linux-riscv@lists.infradead.org, Heiko Carstens , Christian Borntraeger , Sven Schnelle , linux-s390@vger.kernel.org, Mathieu Desnoyers , Andrew Cooper , David Laight , Julia Lawall , Nicolas Palix , Peter Zijlstra , Darren Hart , Davidlohr Bueso , =?UTF-8?q?Andr=C3=A9=20Almeida?= , Alexander Viro , Christian Brauner , Jan Kara , linux-fsdevel@vger.kernel.org Subject: [patch V5 04/12] powerpc/uaccess: Use unsafe wrappers for ASM GOTO References: <20251027083700.573016505@linutronix.de> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Date: Mon, 27 Oct 2025 09:43:48 +0100 (CET) ASM GOTO is miscompiled by GCC when it is used inside a auto cleanup scope: bool foo(u32 __user *p, u32 val) { scoped_guard(pagefault) unsafe_put_user(val, p, efault); return true; efault: return false; } It ends up leaking the pagefault disable counter in the fault path. clang at least fails the build. Rename unsafe_*_user() to arch_unsafe_*_user() which makes the generic uaccess header wrap it with a local label that makes both compilers emit correct code. Same for the kernel_nofault() variants. Signed-off-by: Thomas Gleixner Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Christophe Leroy Cc: linuxppc-dev@lists.ozlabs.org --- arch/powerpc/include/asm/uaccess.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -451,7 +451,7 @@ user_write_access_begin(const void __use #define user_write_access_begin user_write_access_begin #define user_write_access_end prevent_current_write_to_user -#define unsafe_get_user(x, p, e) do { \ +#define arch_unsafe_get_user(x, p, e) do { \ __long_type(*(p)) __gu_val; \ __typeof__(*(p)) __user *__gu_addr = (p); \ \ @@ -459,7 +459,7 @@ user_write_access_begin(const void __use (x) = (__typeof__(*(p)))__gu_val; \ } while (0) -#define unsafe_put_user(x, p, e) \ +#define arch_unsafe_put_user(x, p, e) \ __put_user_size_goto((__typeof__(*(p)))(x), (p), sizeof(*(p)), e) #define unsafe_copy_from_user(d, s, l, e) \ @@ -504,11 +504,11 @@ do { \ unsafe_put_user(*(u8*)(_src + _i), (u8 __user *)(_dst + _i), e); \ } while (0) -#define __get_kernel_nofault(dst, src, type, err_label) \ +#define arch_get_kernel_nofault(dst, src, type, err_label) \ __get_user_size_goto(*((type *)(dst)), \ (__force type __user *)(src), sizeof(type), err_label) -#define __put_kernel_nofault(dst, src, type, err_label) \ +#define arch_put_kernel_nofault(dst, src, type, err_label) \ __put_user_size_goto(*((type *)(src)), \ (__force type __user *)(dst), sizeof(type), err_label)