From patchwork Tue Oct 1 14:30:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 832585 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 1DB351C7B8A; Tue, 1 Oct 2024 14:30:38 +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=1727793038; cv=none; b=Mmol2U3sExdO3iizSZFa7e4QY11p48LiT3nHbhzogzA81mLtsEJfDoYEjbuYScPLovagLzPzgXYr1q/9NW6jPy6yUm1Bw/dnDit5xGQK8eoi//mcE7vt9TYDuPfb6nYqWMbBlGuUcYVIbD8Fqce0vVE4Zjaa2zGBbQzKW7ochl0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727793038; c=relaxed/simple; bh=BJURDqA+9kHR/SvAohPi0bq69sWfM74Vsjzf6VM/9sE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Z5hhdGijmvpVyY77RGD2vV52Q+8u8jBjYhkurZ9G088PWN3DeRvPRLj4jCdfshJ8ZCFCqEejbRJgrIE11O1hoeu1UgUUWU2NsLsSYLTKsGi07+puRqyFT9ao/RR9nhKtkgp+gKyhmbh7LylkqBk6+7HTz3ju82/2+R1+vcm1a4M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=S1MDH09W; 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="S1MDH09W" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58226C4CECD; Tue, 1 Oct 2024 14:30:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1727793038; bh=BJURDqA+9kHR/SvAohPi0bq69sWfM74Vsjzf6VM/9sE=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=S1MDH09W+yroNIfEXQgVJA3ZxAFjz6D8vKLFb+4bMkZzIB4gyr8iDlSdsbqTi6cHx lCTlcuYo1kE6KsbnooUwHaByIBKBN12LqEs5Org7FAMy6B2nbixlbGQR7rctNSm17L K8jBtU0sIpUMcbH06jCaktEGpKH31OXP9noF5LPBJns95bSq6d23GebE8Y3DryPBYu jLe60UIzIojF5h/fhA54MEuzKTWWiwuFpoLqCpwvzwMO0htfAF8ldDQf4GVng9dGH3 DaifR5p/uBWIOw1qiT5YEHpg7HX7uD/gYuK4FeYbhuSX+Al/GsXDgkvnYkj3hz6oAN 7nhQNHb9lQdww== From: Benjamin Tissoires Date: Tue, 01 Oct 2024 16:30:06 +0200 Subject: [PATCH HID v3 2/9] HID: core: save one kmemdup during .probe() Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241001-hid-bpf-hid-generic-v3-2-2ef1019468df@kernel.org> References: <20241001-hid-bpf-hid-generic-v3-0-2ef1019468df@kernel.org> In-Reply-To: <20241001-hid-bpf-hid-generic-v3-0-2ef1019468df@kernel.org> To: Jiri Kosina , Peter Hutterer , Vicki Pfau , Shuah Khan Cc: linux-input@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, Benjamin Tissoires X-Mailer: b4 0.14.1 X-Developer-Signature: v=1; a=ed25519-sha256; t=1727793031; l=1505; i=bentiss@kernel.org; s=20230215; h=from:subject:message-id; bh=BJURDqA+9kHR/SvAohPi0bq69sWfM74Vsjzf6VM/9sE=; b=CiFVQJkbMggNbRUHg6yY8sUusPU1QwO4QmSysy/mqGhUviqifJNXwDanOdtL1+/wMJIRBCfIu eg53Lj4ZDuIDLK+p9jkBwXN3gVDrTQanaqVq7DaaZk3zjuivbWcMicD X-Developer-Key: i=bentiss@kernel.org; a=ed25519; pk=7D1DyAVh6ajCkuUTudt/chMuXWIJHlv2qCsRkIizvFw= Turns out the first kmemdup is only required for the .report_fixup() driver callback. There is no need to do two kmemdup() in a row in case .report_fixup() is not present. Reviewed-by: Peter Hutterer Signed-off-by: Benjamin Tissoires --- no changes in v3 new in v2 --- drivers/hid/hid-core.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index d6bf933623e8..6053e7cdc0c1 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1214,7 +1214,7 @@ int hid_open_report(struct hid_device *device) struct hid_item item; unsigned int size; const __u8 *start; - __u8 *buf; + __u8 *buf = NULL; const __u8 *end; const __u8 *next; int ret; @@ -1235,14 +1235,18 @@ int hid_open_report(struct hid_device *device) return -ENODEV; size = device->bpf_rsize; - buf = kmemdup(start, size, GFP_KERNEL); - if (buf == NULL) - return -ENOMEM; + if (device->driver->report_fixup) { + /* + * device->driver->report_fixup() needs to work + * on a copy of our report descriptor so it can + * change it. + */ + buf = kmemdup(start, size, GFP_KERNEL); + if (buf == NULL) + return -ENOMEM; - if (device->driver->report_fixup) start = device->driver->report_fixup(device, buf, &size); - else - start = buf; + } start = kmemdup(start, size, GFP_KERNEL); kfree(buf);