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 862473C552B for ; Fri, 22 May 2026 09:56:49 +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=1779443811; cv=none; b=urRP+Y3iMRkncEM0AN897FEVXP9sQz38OpDDImg6E/7OwGOi4quoeErb44ztCG2RTIckm7XVZR/NwQiJqT+9U9B1YlWTX1fPFPnqAVJYWzLO3XfKbrccLCwlR1or1My4IHsm8Tpfv1mt7/apoGny8Xi+Dc7ty7HODM60L6/dgT8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779443811; c=relaxed/simple; bh=9S3bhpCCSnE4Jl8KeXsH0H6BKtYWsCDOtF5KfH9qYcE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cJ0uAnjiyafuJFWfyCKvhwxUxFnHtn3MfBS6h0LFZbBAJWQEQ8eX/ihgM5GW8SX/UW+jxSeD6bZkRWTFTa6mH37IlUPkghFCcyqBIqp4NwH6PR96IyiTwkqjYW1G3/gBl1zy98FYk9h59+9SsIOVQByHXgClToUuI9U9i1/lp4A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DaL4UJRY; 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="DaL4UJRY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B17D51F00A3D; Fri, 22 May 2026 09:56:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779443809; bh=8vN/NoLezPEDsyDS+onUAQhVhhGZl3+ewdKbIEUAKPE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=DaL4UJRYwHkj/GX5iunjonDR90BGEe/s2tZteURXKh9dnWNBeiNFQJ5SCTQFlKWc1 IoaN/VFqllJIOmXFbYD/My1O0WPky09e88AD6UxjVLilQ74X2qsQf8eSwcHofKxqkp x2fdFtCWVg8CEvDVsWKDR1hbk9aG9JxRgeryG4+OFZJudEgZXJDz/DG0Ncb/Z/L3Zl FcyQtSxoRElzlt8LBUbY+7CjFGmxm00rqV2ad1H3MH+/t2d29/BxTspVyKkJZnZXjx BTHvomF/B5ZoCQD727ef7OuEQR53uXXLGpyfYaf52Dg9gQr95KnaA15gWPQ4303Td0 pe0/usVMBo6WQ== 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 v1 4/8] powerpc/signal64: Access function descriptor with scoped user access Date: Fri, 22 May 2026 11:56:04 +0200 Message-ID: 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=9S3bhpCCSnE4Jl8KeXsH0H6BKtYWsCDOtF5KfH9qYcE=; b=owGbwMvMwCV2d0KB2p7V54MZT6slMWQJaNhVMD3/0x8wLWxBudhz28rPhauPvNqj3X9PZ4W+l Hj+ncMuHaUsDGJcDLJiiizH/3PvmtH1JTV/6i59mDmsTCBDGLg4BWAiQu8Y/nvO2p3Dviv4nkrW Hr49bW41toeaP0a0/17yU6Sz7/Sn50IMv5i7EjR8fPbPWj1R6bs3V/eFjd8bt1TN59eUOq9n5td eyw4A 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 ee8166fd83dc..bf7fc579d572 100644 --- a/arch/powerpc/kernel/signal_64.c +++ b/arch/powerpc/kernel/signal_64.c @@ -928,8 +928,10 @@ 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 */ @@ -952,5 +954,10 @@ 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