From nobody Thu Sep 11 01:48:09 2025 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 3985732A80C; Wed, 10 Sep 2025 14:37:11 +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=1757515031; cv=none; b=Kx7SCTi/VDOZawHYoJN/COwd4zXdEc8Sug1BNURdlyHiPN6ZDdUkhSNhlQ8QJJ6oDCCUqLl449/e4rlmonicYVwk3oP+7C9znu1w2HIwEymMWSENX8remhQuZHgi6GiSfAgORISERzyTqRGDvX3N0d4zH/mFCqpIe5/1YRKApRg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757515031; c=relaxed/simple; bh=dcXgRxvD4Lbzl66IOipe3Yjd7eUcYeh/PyxSo3B1aCE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=OHPQqhnDd+eUgE0tF0mjbwNvp528LXeLZtB5K3UkXR7nMShUG/Zu7Uylm5H4ItoNJ+57CcovyPimhjIq95O/XAfT5UziQAGDRrW+aNTX69L0ZUkuIwnc9oVWGY+MI4XhW34Qv6u1Fx6sEtcioLTgkHKcEF6S1odZIYROLz1nrvE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=uUi0NwHX; 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="uUi0NwHX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1DEEEC4CEF0; Wed, 10 Sep 2025 14:37:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757515031; bh=dcXgRxvD4Lbzl66IOipe3Yjd7eUcYeh/PyxSo3B1aCE=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=uUi0NwHXAELciPrrvG/LmCCu646U1f9tXLk2Y8ur4dugGN1rdEsTIcwZ9ZSLPwKjm dQwZc43gnWQzlYZf1NWaRPxapfPv121fFnx43DyF25bXTgk8sKBjyn0lATDbR6WKKc /ZMiD8bmRtaLPak0OeZe131hqzvCHJKPYiX36OCmhC0j0CRDiJFHxdvxe0rcixwZpk XECS7bkrU/X24Uix6mFq1sTw14jMkKCXevKU/L2/aDPixqmKPVtAds/l4N+6ogPLOD rxIDwQgUwms/PXrAjgMfzPZIEp+FrRlCxe392EwyAd5OW4SUnG1luStIb3iP4Z/clA molJK5GAVfycQ== From: Christian Brauner Date: Wed, 10 Sep 2025 16:36:46 +0200 Subject: [PATCH 01/32] pidfs: validate extensible ioctls 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="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250910-work-namespace-v1-1-4dd56e7359d8@kernel.org> References: <20250910-work-namespace-v1-0-4dd56e7359d8@kernel.org> In-Reply-To: <20250910-work-namespace-v1-0-4dd56e7359d8@kernel.org> To: Jan Kara , Amir Goldstein , linux-fsdevel@vger.kernel.org Cc: Josef Bacik , Jeff Layton , Mike Yuan , =?utf-8?q?Zbigniew_J=C4=99drzejewski-Szmek?= , Lennart Poettering , Daan De Meyer , Aleksa Sarai , Alexander Viro , Jens Axboe , Tejun Heo , Johannes Weiner , =?utf-8?q?Michal_Koutn=C3=BD?= , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Chuck Lever , linux-nfs@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, netdev@vger.kernel.org, Christian Brauner X-Mailer: b4 0.14.3-dev-385fa X-Developer-Signature: v=1; a=openpgp-sha256; l=1442; i=brauner@kernel.org; h=from:subject:message-id; bh=dcXgRxvD4Lbzl66IOipe3Yjd7eUcYeh/PyxSo3B1aCE=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWQc7GWfm/e37OokHfmHf6Ys5InXvawUHP5ZoMNmY1cqo +Oz+8tCO0pZGMS4GGTFFFkc2k3C5ZbzVGw2ytSAmcPKBDKEgYtTACby+Q8jwzW33TePqJpsP6zB 9u7qhSv2k/K1KwL8fsmnml/Vd1WbPoOR4UDr4ms7U97Ob0qRjn9iZHZItuhrnOpZm0apQwtaDp8 x4wMA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Validate extensible ioctls stricter than we do now. Signed-off-by: Christian Brauner Reviewed-by: Aleksa Sarai Reviewed-by: Jan Kara --- fs/pidfs.c | 2 +- include/linux/fs.h | 14 ++++++++++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/fs/pidfs.c b/fs/pidfs.c index edc35522d75c..0a5083b9cce5 100644 --- a/fs/pidfs.c +++ b/fs/pidfs.c @@ -440,7 +440,7 @@ static bool pidfs_ioctl_valid(unsigned int cmd) * erronously mistook the file descriptor for a pidfd. * This is not perfect but will catch most cases. */ - return (_IOC_TYPE(cmd) =3D=3D _IOC_TYPE(PIDFD_GET_INFO)); + return extensible_ioctl_valid(cmd, PIDFD_GET_INFO, PIDFD_INFO_SIZE_VER0); } =20 return false; diff --git a/include/linux/fs.h b/include/linux/fs.h index d7ab4f96d705..2f2edc53bf3c 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -4023,4 +4023,18 @@ static inline bool vfs_empty_path(int dfd, const cha= r __user *path) =20 int generic_atomic_write_valid(struct kiocb *iocb, struct iov_iter *iter); =20 +static inline bool extensible_ioctl_valid(unsigned int cmd_a, + unsigned int cmd_b, size_t min_size) +{ + if (_IOC_DIR(cmd_a) !=3D _IOC_DIR(cmd_b)) + return false; + if (_IOC_TYPE(cmd_a) !=3D _IOC_TYPE(cmd_b)) + return false; + if (_IOC_NR(cmd_a) !=3D _IOC_NR(cmd_b)) + return false; + if (_IOC_SIZE(cmd_a) < min_size) + return false; + return true; +} + #endif /* _LINUX_FS_H */ --=20 2.47.3