From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793802592; b=i/RdSNt0asZQfI9ar5k2WtrUC4lvp6RMSCKjLT+bRhaRUsHx6a0OFt5K+XKF4fvQoyOB ypzNpxmkgGeTMgVw84Jv7sKALON5/CqZmVbmc8tM1I5pvHT+/LIvUf3h6Aq4gUPp7rhCf L/cUYmkqm7FS6TuVaS1mI8enQYCrsZro3IY8Q8rHIO8PSFeS5lrr+jgwVEqWMJY7xnRya 7fT6uTNl2pmcr49M3c3p0Gp3qeKdHvuM5ns3KaesacsVc+nizLCO/s7YsUn74z/FsUuP9 r1E6w5o8DToQuoKxspTQQE4xahUzWfUiUSiSrz4EraPKaUr1dx7AJP9MgMZdz4jpWkA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793802592; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=0ilVWFxi9WVpNnzRsqaBOTg+OfZ5tNoMsutJK+8d55c=; b=OjB6xkLli955sI2pJnh1pepFIiTgP19ViS/5zClB0LiD4tdB2xKnrOIofl4pVT5SrUp1 iqEVW7143va79sGeh9z0MtTR5zHIQzU/oHBRhzI7ylcSVs935IqS/30qb9F5/ZiSdP/JH rWv08Ek13Ss9pA2522e65cpEyS0vmKJCE/fIoo30puKIZLj+fS5qnBxSzEOjI9cddQFPM PXzyqDNc/iSa4GRGOnnuTcjfc1oWADfW2+Nn8uc0BjrNqszHjSYLwBRUTlQ1Yds6A1cXm kS+0esZ/l5lf+I3+B6FdW2NdmvE5qs0vvX4qy9G1llkmQZcM0J7zrkWz8bcB1sqSl4A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=VQbk8WPy; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 956CD606A326 for ; Wed, 4 Nov 2026 14:29:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=VQbk8WPy Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E1A41F000C1 for ; Wed, 4 Nov 2026 14:29:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793802592; bh=0ilVWFxi9WVpNnzRsqaBOTg+OfZ5tNoMsutJK+8d55c=; h=From:Subject:Reply-To:Cc:In-Reply-To:References:Date; b=VQbk8WPyMZsm6Muf/DcZKTNjVYULm4S+nHDM4eMtuVFaLsHB2aukUWYQSwszb0DPc dIDNvPpzkLEOO93mG6mvqE0n0SsPHYvaImkkiEAsxern5Q0AQDCrNqAxobkd+LuCL2 //9hpPZ19bkwWQ6FAV56002UUlNKoMmBJsXrgLsn7JLNiIoueDW9Xjh3ZunHr+6aCb fac/ew7Af1da68RFHFBwZ+4IF8fT9HQqm0RfTvrtZ55kRLJcSMsoK1fhNlZbausMaz 15RlxbS6/OCgxj9fuZSjc+7xzC6lVp7r3u66e/wI8C09hLtrEHTDdbvGOF5Xz38BL1 0FovNv3OdCS1g== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v2 01/13] cred: gather the rules for acting on a task by uid Reply-To: sashiko-reviews@lists.linux.dev Cc: linux-security-module@vger.kernel.org In-Reply-To: <20261104-b4-cred-ids-v2-1-956213608f16@toxicpanda.com> References: <20261104-b4-cred-ids-v2-0-956213608f16@toxicpanda.com> <20261104-b4-cred-ids-v2-1-956213608f16@toxicpanda.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 04 Nov 2026 14:29:51 +0000 X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > A number of operations let one task act on another without any capability, > because the two belong to the same user: signals, scheduling attributes, > priorities, resource limits, ptrace and more. Each of them compares the > ids of the two credentials by hand. There are twelve such places, in six > flavours that differ in which ids they look at, and nothing says that they > belong together. >=20 > That makes them hard to review and hard to change. Nobody can tell from > one of them whether it differs from its neighbour on purpose. Whoever > wants to know what an equal uid is good for has to find all twelve, and so > does whoever has to change it. A place that is overlooked is a hole. >=20 > Gather the rules in kernel/cred.c, side by side: >=20 > rule of the subject of the object euid 0 used for > [ ... ] > goes with the operation, remain with the caller. >=20 > The callers are converted one by one in the patches that follow. >=20 > Signed-off-by: Josef Bacik Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261104-b4-cred-id= s-v2-0-956213608f16@toxicpanda.com?part=3D1