From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (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 50D21257855; Tue, 4 Aug 2026 01:41:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785807713; cv=none; b=QLNVFYWKGlzQLpyc5sKvC8XLbZw9QEC3JbpJqG/rv91GX44KEs/Ufevtlk/5/rjg/aPd8ecbmPJq5wv2ziGBi8sb5TL+G657qR3PwauyQNG7Wx6+CsbSrVrn1MbIgzmgqfqitZr7yofi12YT0YEcDe6Zb2IhN7QCgCBikjTyYN4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785807713; c=relaxed/simple; bh=5gNcFCB3Vj5V9Zpv0AFqmr3gsHDzKG4qPPzrkhBLJ4w=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=dN5T/06w5+BGNUhG1idpxzvfdMxIIUSWGqcD2SrcNpXj9RneaLaZpMNg17qTys5va9mb9dYyM2K6yXDXdB0W3ujUFks67kFKsT2WC9nSwNJVecErNjSFDAscFrFP69UJH1KU1TX3WLxIBBA2kXMIhkf6NkoYkEQ4J990/su/Xfs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: a4d770728fa511f1aa26b74ffac11d73-20260804 X-CID-CACHE: Type:Local,Time:202608040858+08,HitQuantity:1 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.12,REQID:30382da1-3fe8-4b40-a7f9-4314c8fc7e90,IP:0,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:e7bac3a,CLOUDID:14b31d5e9135692ec2635d0aa24d34bf,BulkI D:nil,BulkQuantity:0,Recheck:0,SF:80|81|82|83|102|865|898,TC:nil,Content:0 |15|52,EDM:-3,IP:nil,URL:99|1,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL: 0,OSI:0,OSA:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_ULS X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: a4d770728fa511f1aa26b74ffac11d73-20260804 X-User: xiaopei01@kylinos.cn Received: from [10.42.12.251] [(10.44.16.150)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_128_GCM_SHA256 128/128) with ESMTP id 1945894045; Tue, 04 Aug 2026 09:41:42 +0800 Message-ID: <1ecf4899-53f3-4688-a3cb-fa29cbf277ee@kylinos.cn> Date: Tue, 4 Aug 2026 09:41:39 +0800 Precedence: bulk X-Mailing-List: linux-input@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] HID: hid-steam: fix uninit-value access in steam_get_serial To: Vicki Pfau , Jiri Kosina Cc: Benjamin Tissoires , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+75f3f9bff8c510602d36@syzkaller.appspotmail.com, syzkaller-bugs@googlegroups.com References: <6a27d055.39669fcc.33b062.008d.GAE@google.com> <0c5f5bcd3d01776615a97d7f23b5c1bff6a2acce.1781092734.git.xiaopei01@kylinos.cn> <85n82qo4-q3q8-8052-1qnr-n7qo12p2p01n@xreary.bet> <5ad5f7d4-a29f-409a-8153-c162059807b2@endrift.com> <16471b27-6f78-4627-874b-9474ee28375c@kylinos.cn> <03420881-edf5-4102-8156-79f314284a07@endrift.com> From: Pei Xiao In-Reply-To: <03420881-edf5-4102-8156-79f314284a07@endrift.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 在 2026/8/4 09:05, Vicki Pfau 写道: > Hi Pei, > > On 8/3/26 5:58 PM, Pei Xiao wrote: >> >> >> 在 2026/8/4 04:39, Vicki Pfau 写道: >>> Hi Jiri, >>> >>> On 8/3/26 12:34 PM, Jiri Kosina wrote: >>>> CCing Vicki Pfau here ... could you please give your Ack to this fix? >>> >>> This was already fixed in 9f8ee99f831b2711624ef81d0abba1d183f28b09 in the series I submitted earlier. I didn't realize there was an open bug report for it. >> Hi maintainer and Vicki, >> I took a look at this commit. In fact, my patch was nearly two months >> earlier than this commit. I had originally thought that this one-line >> patch, especially for an error-path case, had been ignored by the >> maintainer. > > Yes, sorry, I wasn't marked as maintainer at the time and didn't notice it before I wrote my equivalent patch. Jiri just happened to merge mine first. > It's okay. > Vicki > >> >> thanks！ >> Pei. >>> >>>> >>>> Thanks. >>>> >>>> On Wed, 10 Jun 2026, Pei Xiao wrote: >>>> >>>>> The reply buffer in steam_get_serial() is allocated on the stack without >>>>> initialization. In cases where steam_recv_report() returns a short read or >>>>> an error, not all bytes of the buffer are written, leading to subsequent >>>>> access of uninitialized memory when checking reply[0], reply[1], reply[2]. >>>>> >>>>> Zero-initialize the reply array to prevent KMSAN uninit-value warnings. >>>>> >>>>> Logs: >>>>> hid-steam 0003:28DE:1102.0007: unknown main item tag 0x0 >>>>> hid-steam 0003:28DE:1102.0007: unknown main item tag 0x0 >>>>> hid-steam 0003:28DE:1102.0007: : >>>>> USB HID v7f.fd Device [HID 28de:1102] on usb-dummy_hcd.1-1/input0 >>>>> ===================================================== >>>>> BUG: KMSAN: uninit-value in steam_get_serial drivers/hid/hid-steam.c:457 [inline] >>>>> BUG: KMSAN: uninit-value in steam_register+0xd83/0x10e0 drivers/hid/hid-steam.c:965 >>>>> steam_get_serial drivers/hid/hid-steam.c:457 [inline] >>>>> steam_register+0xd83/0x10e0 drivers/hid/hid-steam.c:965 >>>>> steam_probe+0x6f1/0x19b0 drivers/hid/hid-steam.c:1273 >>>>> __hid_device_probe drivers/hid/hid-core.c:2822 [inline] >>>>> hid_device_probe+0x60d/0xb90 drivers/hid/hid-core.c:2859 >>>>> call_driver_probe drivers/base/dd.c:-1 [inline] >>>>> really_probe+0x4d5/0xe40 drivers/base/dd.c:709 >>>>> ... >>>>> >>>>> Local variable reply.i created at: >>>>> steam_get_serial drivers/hid/hid-steam.c:448 [inline] >>>>> steam_register+0x180/0x10e0 drivers/hid/hid-steam.c:965 >>>>> steam_probe+0x6f1/0x19b0 drivers/hid/hid-steam.c:1273 >>>>> >>>>> Reported-by: syzbot+75f3f9bff8c510602d36@syzkaller.appspotmail.com >>>>> Closes: https://lore.kernel.org/lkml/6a27d055.39669fcc.33b062.008d.GAE@google.com/ >>>>> Fixes: c164d6abf384 ("HID: add driver for Valve Steam Controller") >>>>> Signed-off-by: Pei Xiao >>>> >>>> >>>> >>>>> --- >>>>> drivers/hid/hid-steam.c | 2 +- >>>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>>> >>>>> diff --git a/drivers/hid/hid-steam.c b/drivers/hid/hid-steam.c >>>>> index 197126d6e081..f65ad1a21c01 100644 >>>>> --- a/drivers/hid/hid-steam.c >>>>> +++ b/drivers/hid/hid-steam.c >>>>> @@ -445,7 +445,7 @@ static int steam_get_serial(struct steam_device *steam) >>>>> */ >>>>> int ret = 0; >>>>> u8 cmd[] = {ID_GET_STRING_ATTRIBUTE, sizeof(steam->serial_no), ATTRIB_STR_UNIT_SERIAL}; >>>>> - u8 reply[3 + STEAM_SERIAL_LEN + 1]; >>>>> + u8 reply[3 + STEAM_SERIAL_LEN + 1] = { 0 }; >>>>> >>>>> mutex_lock(&steam->report_mutex); >>>>> ret = steam_send_report(steam, cmd, sizeof(cmd)); >>>>> -- >>>>> 2.25.1 >>>>> >>>> >>> >>> Vicki >>