From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZr88Xqwax+ImyeF4zuZQwvMW0SKM6MIuhnKiHOrlokXuKPdUdXOIZSoVdByIodHP4PnbR3q ARC-Seal: i=1; a=rsa-sha256; t=1526281795; cv=none; d=google.com; s=arc-20160816; b=th/1G0dpq/TZGV93yBjnEOO2OvZzTpbsLPuBZJUN2KecKhoBsV3BUskxZUDoEFPPqj moXrSOMsFEUhJ5xbDcAXF54xqQv1T1UpOl1lUVkAv+8OtkV0f9riknYXZLHF9xxZAk4d CXmH1oqW4KJG3cdwI/+3CI+F+cByiCjyDd/rDIlt6htBignOKiLCFVg64exU+hcia7EI qYY5GAKbSZpHXDnNlWsWCH/kshqHfY8tqPOxbD1hbV6z9EZUPs3l+9m8TbXuYGR6Jibv kZhJAMGReTfgfCOI4WXt6LFQTNqg7Fzacw/FzTFyF/RwQLVRw645uN2C0Kv2DLRW95NG Uf7g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature:arc-authentication-results; bh=jyRqyq/1z9KHVu8mayuMY/rvH46RRc6QV7X8JNZ3hoc=; b=BsRr/OBB77KwTYdf2x95OXlw/nx28ZwPO+pIqq6VKEBBcF673JIWYUKH1bsxA3Ou6v DmMli4Z692Q9efxSipS+k1VYtISR6sTnPPDMzYPpie+oW+0z64MohqzqBVfuOTBIqvcC LevNtcmAbPANbRf9avmGJhd0Y/xeO8oromoIrsv1U2Ko0boi16GmHantOkd1YJRvFKpl ZnjosgGvjUXcbFS6XK9lozjbd6BA6Hih63v9paRxxqIQ82IcAW+3/I25APZ3rgAx2MM8 EdDd7IV5nYGGtrrbzZduaZIk37os4dq3QyfOsWsNPsWGJI0eKD2xR6EReyVMHPDlx/Lz ghHg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=V0/1/fwl; spf=pass (google.com: domain of srs0=ywzk=ib=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=ywzk=IB=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=V0/1/fwl; spf=pass (google.com: domain of srs0=ywzk=ib=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=ywzk=IB=linuxfoundation.org=gregkh@kernel.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , "Peter Zijlstra (Intel)" , Alexander Shishkin , Arnaldo Carvalho de Melo , Jiri Olsa , Linus Torvalds , Stephane Eranian , Thomas Gleixner , Vince Weaver , Ingo Molnar Subject: [PATCH 4.4 54/56] perf/x86/msr: Fix possible Spectre-v1 indexing in the MSR driver Date: Mon, 14 May 2018 08:48:59 +0200 Message-Id: <20180514064759.879843333@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180514064754.853201981@linuxfoundation.org> References: <20180514064754.853201981@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1600422459223722103?= X-GMAIL-MSGID: =?utf-8?q?1600422459223722103?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Peter Zijlstra commit 06ce6e9b6d6c09d4129c6e24a1314a395d816c10 upstream. > arch/x86/events/msr.c:178 msr_event_init() warn: potential spectre issue 'msr' (local cap) Userspace controls @attr, sanitize cfg (attr->config) before using it to index an array. Reported-by: Dan Carpenter Signed-off-by: Peter Zijlstra (Intel) Cc: Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/perf_event_msr.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/arch/x86/kernel/cpu/perf_event_msr.c +++ b/arch/x86/kernel/cpu/perf_event_msr.c @@ -1,4 +1,5 @@ #include +#include enum perf_msr_id { PERF_MSR_TSC = 0, @@ -115,9 +116,6 @@ static int msr_event_init(struct perf_ev if (event->attr.type != event->pmu->type) return -ENOENT; - if (cfg >= PERF_MSR_EVENT_MAX) - return -EINVAL; - /* unsupported modes and filters */ if (event->attr.exclude_user || event->attr.exclude_kernel || @@ -128,6 +126,11 @@ static int msr_event_init(struct perf_ev event->attr.sample_period) /* no sampling */ return -EINVAL; + if (cfg >= PERF_MSR_EVENT_MAX) + return -EINVAL; + + cfg = array_index_nospec((unsigned long)cfg, PERF_MSR_EVENT_MAX); + if (!msr[cfg].attr) return -EINVAL;