From patchwork Wed Jan 24 11:26:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 13528947 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 6CE792C684; Wed, 24 Jan 2024 11:27:10 +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=1706095630; cv=none; b=JZJ2CiStkme3egp0naAN+aBSeLf9FIdYstvb7D95YzDgqsrfoMymdVVeWZKYPKdJF8F85hNKxjXJHi7GTsOdVOEEAMlGUas/Ce3RreMg60slGSU6D/ybvaWo/9xi8nPj/9A6a94Q9lTNX2l+BVhReeG1f+oLnsE4eGQb4jF5P8o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706095630; c=relaxed/simple; bh=alQWMBFXA1hw7IIWXSpJ6i4inmySS5LtlbuTmaNyvl4=; h=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To:Cc; b=CiR4wt/Uch6WAgfDwe4Yhw66szMwDjBmP2OzxvZZGNnlw8V4XQMV7r11eBSKvIU5uWAPId00EnXrmdW/zUsIZjbF6QFKQA7ga1fsfuiepNDGVsGe8vZGQggG8eDYHJI6JgJaZlApmQSE05MyFH7Nfpr3XQPOT8mK7rLmda86BQ0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Y9CyT7/z; 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="Y9CyT7/z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 59A84C433C7; Wed, 24 Jan 2024 11:27:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706095630; bh=alQWMBFXA1hw7IIWXSpJ6i4inmySS5LtlbuTmaNyvl4=; h=From:Subject:Date:To:Cc:From; b=Y9CyT7/zJOgHijuFWNtRE5BK0H0gmMJs7J47B3RhKobd0Cdg95Ffr0gwjegsbTJo9 l5jFT2D0k8Wyf1dZoIrlgwJABziL/uMh7EqvOQiCy+6H9e0FbnL78Ek/1NQrXTTBFz Yi+KDg63/QF6strX05Jg1NdW6DyP8VWGmY+t6rcCnEPltwieHTEDnB/ORgwltAMHQt 4rw7g0q9i+7z20mO68w9Ez+/gi8Fu2qEXqr+W8u7p4E6jUeBuUZJ0xAn0Zlv0I2WPD x52l2BtjQTejwsCFKqIkqM15PYksEtxlrVS+kzYNrgUpw05Xu/ypl++kRvycDZC1ph dnwJ8F4Z5hbfA== From: Benjamin Tissoires Subject: [PATCH v2 0/3] HID: bpf: couple of upstream fixes Date: Wed, 24 Jan 2024 12:26:56 +0100 Message-Id: <20240124-b4-hid-bpf-fixes-v2-0-052520b1e5e6@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-B4-Tracking: v=1; b=H4sIAAD0sGUC/32NQQ6CMBBFr0Jm7Zh22lB1xT0MiwJTOtEAaQ3RE O5u5QAu3/95/2+QOQlnuFUbJF4lyzwVoFMFffTTyChDYSBFVmky2FmMMmC3BAzy5ox1TVd1CUx kLBRtSXwUxbq3haPk15w+x8Oqf+mfsVWjQu918L0z1jjXPDhN/DzPaYR23/cvIfSokbEAAAA= To: Jiri Kosina , Benjamin Tissoires , Dan Carpenter , Daniel Borkmann , Andrii Nakryiko Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, Benjamin Tissoires , stable@vger.kernel.org X-Mailer: b4 0.12.4 X-Developer-Signature: v=1; a=ed25519-sha256; t=1706095628; l=2390; i=bentiss@kernel.org; s=20230215; h=from:subject:message-id; bh=alQWMBFXA1hw7IIWXSpJ6i4inmySS5LtlbuTmaNyvl4=; b=j5lHHgQgLoXVZiipVjKowReOGI8kG/sxaAYoHUCxIixkXKDGr6uZidECS+6mEjacbAFlkw3y8 0leuu0JRJH5Bdo74vBNHfnY00B3a2snuwqLxHwVesgj3F0kFQKh3wI/ X-Developer-Key: i=bentiss@kernel.org; a=ed25519; pk=7D1DyAVh6ajCkuUTudt/chMuXWIJHlv2qCsRkIizvFw= Hi, This is the v2 of this series of HID-BPF fixes. I have forgotten to include a Fixes tag in the first patch and got a review from Andrii on patch 2. And this first patch made me realize that something was fishy in the refcount of the hid devices. I was not crashing the system even if I accessed the struct hid_device after hid_destroy_device() was called, which was suspicious to say the least. So after some debugging I found the culprit and realized that I had a pretty nice memleak as soon as one HID-BPF program was attached to a HID device. The good thing though is that this ref count prevents a crash in case a HID-BPF program attempts to access a removed HID device when hid_bpf_allocate_context() has been called but not yet released. Anyway, for reference, the cover letter of v1: --- Hi, these are a couple of fixes for hid-bpf. The first one should probably go in ASAP, after the reviews, and the second one is nice to have and doesn't hurt much. Thanks Dan for finding out the issue with bpf_prog_get() Cheers, Benjamin To: Jiri Kosina To: Benjamin Tissoires To: Dan Carpenter To: Daniel Borkmann To: Andrii Nakryiko Cc: Cc: Cc: Signed-off-by: Benjamin Tissoires --- Changes in v2: - add Fixes tags - handled Andrii review (use of __bpf_kfunc_start/end_defs()) - new patch to fetch ref counting of struct hid_device - Link to v1: https://lore.kernel.org/r/20240123-b4-hid-bpf-fixes-v1-0-aa1fac734377@kernel.org --- Benjamin Tissoires (3): HID: bpf: remove double fdget() HID: bpf: actually free hdev memory after attaching a HID-BPF program HID: bpf: use __bpf_kfunc instead of noinline drivers/hid/bpf/hid_bpf_dispatch.c | 101 ++++++++++++++++++++++++++---------- drivers/hid/bpf/hid_bpf_dispatch.h | 4 +- drivers/hid/bpf/hid_bpf_jmp_table.c | 39 +++++++------- include/linux/hid_bpf.h | 11 ---- 4 files changed, 95 insertions(+), 60 deletions(-) --- base-commit: fef018d8199661962b5fc0f0d1501caa54b2b533 change-id: 20240123-b4-hid-bpf-fixes-662908fe2234 Best regards,