From patchwork Tue Sep 10 14:43:38 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 13798652 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 EB28119ABB6; Tue, 10 Sep 2024 14:43:54 +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=1725979435; cv=none; b=VxLQiZWwM6+eeeFEWsUdIkvoFUP3DHB6lpUvL0Z6Gte3C/SNHRmmUGWrsnx8dKkByED0lViv3qC1yoC1MDf1ihxA/+ByMESFPue+LJmjD2dC1/xs7rcdynT3bLzkNZB3O8elgZpkSRDHf1ZDmiVrjpis3IA+RbiaRZIXKxRL0B8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725979435; c=relaxed/simple; bh=8Rv7wHGS5vnx8vrFXpuXccJrUODHQOZZwz7abDTtL1w=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=c02/3cCjwVDH40qGeXoDqBVXykhKyH2qqSIq+t2Z2FYIxV17h4oNrsv44mZjJionjNWWz+nHIhz/xE3l7VkWlBrfpNsODGp99APGw5XWawnIaBsC6cnscGk/k98hwrQEHcum8Il7ncwA5f2YemwX87IwCWPymyT5Hn/M3c5LtUM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nbIswF3R; 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="nbIswF3R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA90DC4CECD; Tue, 10 Sep 2024 14:43:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725979434; bh=8Rv7wHGS5vnx8vrFXpuXccJrUODHQOZZwz7abDTtL1w=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=nbIswF3RwCl57bL6Bt07Dr2YJ3pPLFxXZxMdp8Lpb837Z5XKNgOQz1sebIUyi2rl2 2zRfXVRZID+X7LerA3Pc9uXmD3tJsjnzJyBeJ/rhJx1jH1F3udgF+Cv0Kf9tbOAfKR hsABs1tKRvBoot+IU/Hut3n4uM3E0hpwvhlV8Jw4vdhyM0vVQHsVJ1TFl0vE8mxDSt 9r6W07Fk4W8LgtawXyf2VNCwZkybzOzXacYurNwaR/WtJ21XJSUqTDBY7fThTIqfWa 8tMsylbEMPtW2nnoDVaXqn94Ri57TN1g6BDjv/Dg46/jcWaxzdfLPXkdBpyVk2c4AU SFdVf8iJARZ4w== From: Benjamin Tissoires Date: Tue, 10 Sep 2024 23:43:38 +0900 Subject: [PATCH HID v2 02/11] HID: core: save one kmemdup during .probe() Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240910-hid-bpf-hid-generic-v2-2-083dfc189e97@kernel.org> References: <20240910-hid-bpf-hid-generic-v2-0-083dfc189e97@kernel.org> In-Reply-To: <20240910-hid-bpf-hid-generic-v2-0-083dfc189e97@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=1725979428; l=1424; i=bentiss@kernel.org; s=20230215; h=from:subject:message-id; bh=8Rv7wHGS5vnx8vrFXpuXccJrUODHQOZZwz7abDTtL1w=; b=h9Sdeen8uG5RlGASV0hN9wRWgXmQw8z5HNVcL/zvvgetMiG/cvF2VjrPn/OV33cwj7x4qSVpe HodTtFpOazUDtxOcJTY+fv4sk6EqXgYPtBw8MSYWn4AVhy/laVKnexJ 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 raw in case .report_fixup() is not present. Signed-off-by: Benjamin Tissoires --- 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 a5f5415571cb..172746a082f9 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1206,7 +1206,7 @@ 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; @@ -1227,14 +1227,18 @@ int hid_open_report(struct hid_device *device) if (WARN_ON(!start)) return -ENODEV; - 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);