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=1793717250; b=NoqgYgIaYDIjEgJLJh2iRU1YWLSbYmCh6K3XCxe9jGyJQPDncXEW0fFhep6II1VsDYdI 9iJbkLm4+ff8LgbgbaP9hmtqkvAZs4qxiyvm9Hz2gRvSDhuR05cNw2OgEnKKjRY25GVV/ wpogIrEAW+Eem+OV5u94PTgM69Ik68Wmd3B9mUoI825neofeDzNpAjG46y2FzzbiWGy0J 9huNlS3yMXak3s8KgB2SmfFfrksJ0p/goyKBCqFAV/tCr86sFr5BKqqi0/2YB72W8C+ss D31vNrFtcwmM5G7LjrbMxTTpwk3bqsUz5iMKypdePHa+NWVJUNkxA4ULPu0N7nTNPZg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793717250; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=CcwQtKt8p98z3nZ6v7GVVoJYg9XQ/4wAmXztnPTRoMM=; b=jzRXmdNlPq//ttm+9RwHF0NdGiAbnff70sCRbspbFHBgGgTNW28GS3gsSSBBg0aFNWAc RUbjUeNjZeUFC0mMF0atUM0pzfIpa8T8ke/+3e/iDqlclxV69J9aHosXPlqu67ifdGFiZ 5cYB6xkmuahR77uAm/QmYRGMakwiy8yuMd8gLQxflta+0wrziuUjcoQtJS5m+thE5lpw4 5kGBe3ehwcdC0fJ2BSE3TxMfw+DS75I9CR0be3h+cbkWCO7HQXZYyqZv/rMJqpp9gqZfY Yo0nEodokPKIoMQKmV1Va92x8RqjnB1JLYj/4GCZwpkTWPpyUno2NwY4d7jlNm+JRig== 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=Iq9eyMHs; 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 0FA2B606A324; Tue, 3 Nov 2026 14:47:29 +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=Iq9eyMHs Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D7B51F000C1; Tue, 3 Nov 2026 14:47:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793717249; bh=CcwQtKt8p98z3nZ6v7GVVoJYg9XQ/4wAmXztnPTRoMM=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Iq9eyMHstCQbbT4lxVLStphZgJXCXZr1LD+8HR6zoL6SI3XDnTvNIL7/IDGpiWoGp 6LRT+Jf2/rw2ZagpH0lSWUv8gDqvFkOho1ggYUba4Zt/1LHRWciRdIZRjWztqUNVxr Gy5Z8RmZ/iuH+xhZaiYaZPzNzQsw6jFgukUstj9zpOX3Xo50vy1HO6bgCkwskOaFTa 8furxKuxrl5c3bNBuHpiiGPAiANnExVG5tU1aQQd6AWUt1g45eCWa3KG+rhy8MieOn t6P70wg04vvmSk1BoQp4Tq9a7jvOLdGxp0nvIUBUxQGtmJ/JQPHcuWhvMX3cPcoloy y+Nze7fZpewzA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH RFC 01/38] PCI/proc: don't truncate the position of config space accesses Reply-To: sashiko-reviews@lists.linux.dev To: "Christian Brauner" Cc: "Linus Torvalds" , "Jann Horn" , "Josef Bacik" , "Chris Mason" , "Jeff Layton" , NeilBrown , "Eric Dumazet" , "Thomas Gleixner" , "Al Viro" , "Jonathan Corbet" , "Christoph Hellwig" , "Greg Kroah-Hartman" , "Joel Granados" , "Kees Cook" , "Jan Kara" , "Jan Kara" , linux-s390@vger.kernel.org, coreteam@netfilter.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-usb@vger.kernel.org, samba-technical@lists.samba.org, linux-m68k@lists.linux-m68k.org, linux-serial@vger.kernel.org, "Takashi Iwai" , linux-ext4@vger.kernel.org, "Chuck Lever" , tytso@mit.edu, "Heiko Carstens" , "Vasily Gorbik" , "Alexander Gordeev" , "Christian Borntraeger" In-Reply-To: <20261102-work-procfs-bugfixes-v1-1-59422ed3e465@kernel.org> References: <20261102-work-procfs-bugfixes-v1-0-59422ed3e465@kernel.org> <20261102-work-procfs-bugfixes-v1-1-59422ed3e465@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 03 Nov 2026 14:47:27 +0000 X-Mailing-List: linux-hwmon@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > proc_bus_pci_write() truncates the file position to an int. A pwrite() > at an offset like 0xfffff000 turns it negative, the check against the > size of the config space passes and the count it clamps to ends up > larger than what was written. The loop then reads past the end of the > caller's buffer and writes all of it into config space at negative > offsets, which pci_user_write_config_*() pass on to the config > accessors unchecked. The write also returns more than it was asked to > write. >=20 > An offset above 4G that truncates to a small positive value writes to > the start of config space instead. proc_bus_pci_read() keeps the > position in an unsigned int, so a read at such an offset returns the > start of config space instead of hitting EOF. >=20 > Check the position against the size of the config space before > narrowing it. >=20 > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > Cc: stable@vger.kernel.org > Signed-off-by: Christian Brauner (Amutable) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261102-work-procf= s-bugfixes-v1-0-59422ed3e465@kernel.org?part=3D1