From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C61152C11EE for ; Tue, 2 Jun 2026 08:46:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780390020; cv=none; b=SUiB2PdfmbLGlUhXFCoa8O1l6wC3j3uofxfHkaWcrFbz+DM+Fs3Z9b7GkZy0eQguQXZnYdvWlHSgVfnicdTQ43I0V9UaLo6+/txOGff1gaetOEY+E6mKVDJa26bisNnrJBt+9OuyYcBDqPkAWECDPCb2CsYtFviv6EsqnDH/c4I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780390020; c=relaxed/simple; bh=4aksLooy4XCvM5n/sIPCKsUfuKkAa5e7DCDqbcxCFz4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YeRytQ0oUCcskkjQrGjLObyIql3aZiZOxZTBwn+5j9WEKuHsLy3LHj3NOCXIwsui3MY3K/rjwU6HG0wwVdYtIazcAgmBiRex148YdstjYebe9adpNJ3mY0kxOv+L3xoA34vpoLAGpshmVl9E6SmU3RbRwqHO7dDUAHOxNM9N5sc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TChqJwKI; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TChqJwKI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0548C1F00893; Tue, 2 Jun 2026 08:46:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780390019; bh=sMG/2rxZYMjEPPBvwv4bSmWW/2cnEvqzHzFFMwcW/54=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=TChqJwKIsLx5o6EZivYMTNC1TWMC37L1gx+GW4rJSYfwykZvJLBT292S+1X5NFTGs Jk+fnS19J99iQz90W7a3/bu+hXZfrC2OQRaufm6xSbl6KTRE7p/3NISpX4LPfW5cpb zXnY1Siy9WKZ7ZF37CqJoaGttxRAatkV/JsLG1DguyIkmJhB5W9dHvQHgDujWI4vXo fmH/ry14vvn58H5bDSEv2KxtUgAQawzZh+GvlZbequNj+JaXTH11ogN1SYPUvpiRBS 1jXoi283PCVIfOgExKJXItUZSV4MLA0B4adS9zGUV1UO3zAiAvWM3i8X/0/JRD69Qp Ymm4HYO5tzXnw== From: "Christophe Leroy (CS GROUP)" To: Michael Ellerman , Nicholas Piggin , Madhavan Srinivasan Cc: "Christophe Leroy (CS GROUP)" , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: [PATCH v2 4/8] powerpc/signal64: Access function descriptor with scoped user access Date: Tue, 2 Jun 2026 10:46:33 +0200 Message-ID: <6492f5d9ace4ae9dd39ce45b509cd3790285b44a.1780389863.git.chleroy@kernel.org> X-Mailer: git-send-email 2.54.0 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=openpgp-sha256; l=1246; i=chleroy@kernel.org; h=from:subject:message-id; bh=4aksLooy4XCvM5n/sIPCKsUfuKkAa5e7DCDqbcxCFz4=; b=owGbwMvMwCV2d0KB2p7V54MZT6slMWTJzcid6Fsj7a7J5Jpve0L/UfWq71tnJbrOWsWzb4HsQ 6fZi/4XdZSyMIhxMciKKbIc/8+9a0bXl9T8qbv0YeawMoEMYeDiFICJGEow/E/q8Jn7Oqq6nd89 L8xl1yMRz1lZb4o55u4XOP1i1+4jU34xMvy80rVfp/C+0csds/ZL6b9s8DF5I9WTcbfy08OHG5y cLjMBAA== X-Developer-Key: i=chleroy@kernel.org; a=openpgp; fpr=10FFE6F8B390DE17ACC2632368A92FEB01B8DD78 Content-Transfer-Encoding: 8bit Access the function descriptor of the handler within a scoped user access block. Signed-off-by: Christophe Leroy (CS GROUP) --- arch/powerpc/kernel/signal_64.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c index 4ff8ad5d60d0..d23a980b32a8 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -932,8 +932,10 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set, struct func_desc __user *ptr = (struct func_desc __user *)ksig->ka.sa.sa_handler; - err |= get_user(regs->ctr, &ptr->addr); - err |= get_user(regs->gpr[2], &ptr->toc); + scoped_user_read_access(ptr, badfunc) { + unsafe_get_user(regs->ctr, &ptr->addr, badfunc); + unsafe_get_user(regs->gpr[2], &ptr->toc, badfunc); + } } /* enter the signal handler in native-endian mode */ @@ -956,5 +958,10 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set, badframe: signal_fault(current, regs, "handle_rt_signal64", frame); + return 1; + +badfunc: + signal_fault(current, regs, __func__, (void __user *)ksig->ka.sa.sa_handler); + return 1; } -- 2.54.0