From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 23B4D1E492D for ; Fri, 1 May 2026 02:05:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777601133; cv=none; b=kZ3R26klCp7kZYftSHQi9VbMOmX9yjVEpPXx/G0PASRlKhhoxQ5I8XZXcJMcDbhHgVoa7bDD7AsYOoriLoV1I1GY1+K7HM1vmQzNetx+KN3+hsdPQccOS3bnf5A9+DRdSXHuF50NEao8Gp6MgNw/0mP33Sw/WR4EkZY+TV1pp5Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777601133; c=relaxed/simple; bh=FfNzHKCzWM5qOuj6/OdGw2uNcDY9IOAH0R6ZHmLTHvU=; h=Date:From:To:cc:Subject:In-Reply-To:Message-ID:References: MIME-Version:Content-Type; b=N5Ofj60Uj8B8Rvw5B3aWid3gn9TzOR7jCDCQ9gzezgLhLmBejs1u2HksAYjxNqbrZDV/so+isgoSnOYiIRo/7SEBDjlVp8tJqXR4NBaTP13pde9RqLKO9k0CJIphObdTTvqivggJ7bFaWH01djUHnDmlb4X4rDri8zlRQFczngE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qQWN3kym; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="qQWN3kym" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3DA2FC2BCB3; Fri, 1 May 2026 02:05:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777601132; bh=FfNzHKCzWM5qOuj6/OdGw2uNcDY9IOAH0R6ZHmLTHvU=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=qQWN3kymasnI7PWAo8rAMcUZhcym3LANYUBJQpVw1+yvW+sF15UrwCcb1IQn0W6Bw sLWdXAYoxCnhRvSSbH4LTutOWeKhIkfldRATJFXSNfnXp3v0Qb1qdWYkCcixMfyWM5 FwdfH3X4+iPL9kZPTIU88yqapPnYMutv11I2ZyQZ2V+H+vE4aCEKOTHpxlxH26oqGk jvo8z1/XBDQHLzU8xug1ZJF1vfffhCLZdpzQ8WkwogwT25dJktSWyBkIUDB0GFV96w FwFH80o1ZNEGqAuMzQcoZMyKBkeXLfhsMGVi2RZJieCU8SSw05VNYNQ/2oSjLyBvvo 5y55H4FLNeItw== Date: Thu, 30 Apr 2026 20:05:23 -0600 (MDT) From: Paul Walmsley To: Michael Neuling cc: =?ISO-8859-15?Q?Bj=F6rn_T=F6pel?= , "Mike Rapoport (Microsoft)" , "Vishal Moola (Oracle)" , Albert Ou , Aleksa Paunovic , Aleksandar Rikalo , Alexandre Ghiti , Andrew Jones , Andrew Morton , Arnd Bergmann , David Hildenbrand , Djordje Todorovic , Guo Ren , Junhui Liu , Kevin Brodsky , Lorenzo Stoakes , Nam Cao , Oleg Nesterov , Oscar Salvador , Palmer Dabbelt , Paul Walmsley , Qinglin Pan , Raj Vishwanathan4 , linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH 2/5] riscv: ptrace: Fix register corruption in compat_riscv_gpr_set on error In-Reply-To: <20260409091143.1348853-3-mikey@neuling.org> Message-ID: <78b4e931-9ec7-14b6-1487-906652a65ce8@kernel.org> References: <20260409091143.1348853-1-mikey@neuling.org> <20260409091143.1348853-3-mikey@neuling.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Hi Mikey, On Thu, 9 Apr 2026, Michael Neuling wrote: > compat_riscv_gpr_set() calls cregs_to_regs() unconditionally, even when > user_regset_copyin() fails. Since cregs is an uninitialized stack > variable, a copyin failure causes uninitialized stack data to be written > into the target task's pt_regs, corrupting its register state and > potentially leaking kernel stack contents. > > Only call cregs_to_regs() when user_regset_copyin() succeeds. > > Fixes: 4608c15959 ("riscv: compat: ptrace: Add compat_arch_ptrace implement") > Signed-off-by: Michael Neuling > Assisted-by: Cursor:claude-4.6-opus-high-thinking Thanks. I'm wondering if we have the same issue in compat_restore_sigcontext(). Care to add that to your patch if you agree? - Paul