From: "zhangfei.gao@foxmail.com" <zhangfei.gao@foxmail.com>
To: Fenghua Yu <fenghua.yu@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>,
Joerg Roedel <joro@8bytes.org>,
jean-philippe <jean-philippe@linaro.org>,
Ravi V Shankar <ravi.v.shankar@intel.com>,
Tony Luck <tony.luck@intel.com>, Ashok Raj <ashok.raj@intel.com>,
Peter Zijlstra <peterz@infradead.org>,
Dave Hansen <dave.hansen@linux.intel.com>, x86 <x86@kernel.org>,
linux-kernel <linux-kernel@vger.kernel.org>,
iommu <iommu@lists.linux-foundation.org>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Andy Lutomirski <luto@kernel.org>,
Josh Poimboeuf <jpoimboe@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH v4 05/11] iommu/sva: Assign a PASID to mm on PASID allocation and free it on mm exit
Date: Fri, 15 Apr 2022 19:52:03 +0800 [thread overview]
Message-ID: <tencent_CD35B6A6FBB48186B38EF641F088BAED1407@qq.com> (raw)
In-Reply-To: <YllN/OmjpYdT1tO9@otcwcpicx3.sc.intel.com>
On 2022/4/15 下午6:50, Fenghua Yu wrote:
> Hi, Zhangfei,
>
> On Fri, Apr 15, 2022 at 06:14:09PM +0800, zhangfei.gao@foxmail.com wrote:
>>
>> On 2022/4/15 下午5:51, Fenghua Yu wrote:
>>> On Thu, Apr 14, 2022 at 06:08:09PM +0800, zhangfei.gao@foxmail.com wrote:
>>>> On 2022/4/12 下午11:35, zhangfei.gao@foxmail.com wrote:
>>>>> Hi, Fenghua
>>>>>
>>>>> On 2022/4/12 下午9:41, Fenghua Yu wrote:
>>> From a6444e1e5bd8076f5e5c5e950d3192de327f0c9c Mon Sep 17 00:00:00 2001
>>> From: Fenghua Yu <fenghua.yu@intel.com>
>>> Date: Fri, 15 Apr 2022 00:51:33 -0700
>>> Subject: [RFC PATCH] iommu/sva: Fix PASID use-after-free issue
>>>
>>> A PASID might be still used even though it is freed on mm exit.
>>>
>>> process A:
>>> sva_bind();
>>> ioasid_alloc() = N; // Get PASID N for the mm
>>> fork(): // spawn process B
>>> exit();
>>> ioasid_free(N);
>>>
>>> process B:
>>> device uses PASID N -> failure
>>> sva_unbind();
>>>
>>> Dave Hansen suggests to take a refcount on the mm whenever binding the
>>> PASID to a device and drop the refcount on unbinding. The mm won't be
>>> dropped if the PASID is still bound to it.
>>>
>>> Fixes: 701fac40384f ("iommu/sva: Assign a PASID to mm on PASID allocation and free it on mm exit")
>>>
>>> Reported-by: Zhangfei Gao <zhangfei.gao@foxmail.com>
>>> Suggested-by: Dave Hansen" <dave.hansen@linux.intel.com>
>>> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
>>> ---
>>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 6 ++++++
>>> drivers/iommu/intel/svm.c | 4 ++++
>>> 2 files changed, 10 insertions(+)
>>>
>>> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
>>> index 22ddd05bbdcd..3fcb842a0df0 100644
>>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
>>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
>>> @@ -7,6 +7,7 @@
>>> #include <linux/mmu_context.h>
>>> #include <linux/mmu_notifier.h>
>>> #include <linux/slab.h>
>>> +#include <linux/sched/mm.h>
>>> #include "arm-smmu-v3.h"
>>> #include "../../iommu-sva-lib.h"
>>> @@ -363,6 +364,9 @@ arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm, void *drvdata)
>>> mutex_lock(&sva_lock);
>>> handle = __arm_smmu_sva_bind(dev, mm);
>>> + /* Take an mm refcount on a successful bind. */
>>> + if (!IS_ERR(handle))
>>> + mmget(mm);
>>> mutex_unlock(&sva_lock);
>>> return handle;
>>> }
>>> @@ -372,6 +376,8 @@ void arm_smmu_sva_unbind(struct iommu_sva *handle)
>>> struct arm_smmu_bond *bond = sva_to_bond(handle);
>>> mutex_lock(&sva_lock);
>>> + /* Drop an mm refcount. */
>>> + mmput(bond->mm);
>>> if (refcount_dec_and_test(&bond->refs)) {
>>> list_del(&bond->list);
>>> arm_smmu_mmu_notifier_put(bond->smmu_mn);
>>> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
>>> index 23a38763c1d1..345a0d5d7922 100644
>>> --- a/drivers/iommu/intel/svm.c
>>> +++ b/drivers/iommu/intel/svm.c
>>> @@ -403,6 +403,8 @@ static struct iommu_sva *intel_svm_bind_mm(struct intel_iommu *iommu,
>>> goto free_sdev;
>>> list_add_rcu(&sdev->list, &svm->devs);
>>> + /* Take an mm refcount on binding mm. */
>>> + mmget(mm);
>>> success:
>>> return &sdev->sva;
>>> @@ -465,6 +467,8 @@ static int intel_svm_unbind_mm(struct device *dev, u32 pasid)
>>> kfree(svm);
>>> }
>>> }
>>> + /* Drop an mm reference on unbinding mm. */
>>> + mmput(mm);
>>> }
>>> out:
>>> return ret;
>> This patch can not be applied on 5.18-rc2 for intel part.
> What error do you see? Could you please send to me errors?
>
> I download this patch from:
> https://lore.kernel.org/lkml/YllADL6uMoLllzQo@fyu1.sc.intel.com/raw
> git am to either v5.18-rc2 or the latest upstream without any issue.
It is my copy paste issue.
I have tested, nginx woks well.
Other than the following issue,
Each time /sbin/nginx will alloc ioasid but not free.
which I think it maybe nginx issue or the mis-usage, will ask there.
Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
>
>> It should work for arm.
>>
>> In fact I have a similar patch at hand but pending since I found an issue.
>>
>> I start & stop nginx via this cmd.
>> //start
>> sudo sbin/nginx // this alloc an ioasid=1
>> //stop
>> sudo sbin/nginx -s quit // this does not free ioasid=1, but still alloc
>> ioasid=2.
>> So ioasid will keep allocated but not freed if continue start/stop nginx,
>> though not impact the nginx function.
>>
>> stop nginx with -s quit still calls
>> src/core/nginx.c
>> main -> ngx_ssl_init -> openssl engine: bind_fn -> ... -> alloc asid
>> But openssl engine: ENGINE_free is not called
>>
>> Still in checking nginx code.
>>
>> Or do you test with nginx?
> On my X86 machine, nginx doesn't trigger the kernel sva binding function
> to allocate ioasid. I tried pre- nstalled nginx/openssl and also tried my built
> a few versions of nginx/openssl. nginx does call OPENSSL_init_ssl() but
> doesn't go to the binding function. Don't know if it's my configuration issue.
> Maybe you can give me some advice?
I am using openssl engine, which use crypto driver and using sva via uacce.
nginx -> openssl -> openssl engine -> sva related.
>
> I test the patch with a few internal test tools and observe mmget()/mmput()
> works fine in various cases.
OK, thanks
next prev parent reply other threads:[~2022-04-15 11:53 UTC|newest]
Thread overview: 113+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-07 23:02 [PATCH v4 00/11] Re-enable ENQCMD and PASID MSR Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 01/11] iommu/sva: Rename CONFIG_IOMMU_SVA_LIB to CONFIG_IOMMU_SVA Fenghua Yu
2022-02-08 2:39 ` Lu Baolu
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 02/11] mm: Change CONFIG option for mm->pasid field Fenghua Yu
2022-02-08 2:40 ` Lu Baolu
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 03/11] iommu/ioasid: Introduce a helper to check for valid PASIDs Fenghua Yu
2022-02-08 2:40 ` Lu Baolu
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 04/11] kernel/fork: Initialize mm's PASID Fenghua Yu
2022-02-14 17:23 ` Thomas Gleixner
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 05/11] iommu/sva: Assign a PASID to mm on PASID allocation and free it on mm exit Fenghua Yu
2022-02-08 2:41 ` Lu Baolu
2022-02-08 15:01 ` Fenghua Yu
2022-02-10 3:16 ` Jacob Pan
2022-02-10 16:27 ` Fenghua Yu
2022-02-10 17:24 ` Luck, Tony
2022-02-10 18:31 ` Fenghua Yu
2022-02-10 23:52 ` Fenghua Yu
2022-02-10 18:49 ` Jacob Pan
2022-02-10 23:15 ` Fenghua Yu
2022-02-11 22:00 ` Dave Hansen
2022-02-14 17:24 ` Thomas Gleixner
2022-02-15 9:55 ` Joerg Roedel
[not found] ` <tencent_F6830A1196DB4C6A904D7C691F0D961D1108@qq.com>
2022-04-11 14:10 ` Dave Hansen
2022-04-11 14:20 ` zhangfei.gao
2022-04-11 14:36 ` Dave Hansen
2022-04-11 14:44 ` zhangfei.gao
2022-04-11 14:52 ` Dave Hansen
2022-04-11 15:13 ` zhangfei.gao
2022-04-12 7:04 ` zhangfei.gao
2022-04-12 13:41 ` Fenghua Yu
2022-04-12 14:39 ` Dave Hansen
2022-04-15 9:59 ` Fenghua Yu
2022-04-12 15:35 ` zhangfei.gao
2022-04-14 10:08 ` zhangfei.gao
2022-04-15 9:51 ` Fenghua Yu
[not found] ` <99bcb9f5-4776-9c40-a776-cdecfa9e1010@foxmail.com>
2022-04-15 10:14 ` zhangfei.gao
2022-04-15 10:50 ` Fenghua Yu
2022-04-15 11:52 ` zhangfei.gao [this message]
2022-04-15 12:37 ` Fenghua Yu
2022-04-16 1:30 ` zhangfei.gao
2022-04-15 19:07 ` Fenghua Yu
2022-04-15 21:00 ` Jacob Pan
2022-04-16 1:43 ` zhangfei.gao
2022-04-18 18:14 ` Jacob Pan
2022-04-19 1:02 ` zhangfei.gao
2022-04-18 6:34 ` Tian, Kevin
2022-04-18 18:11 ` Jacob Pan
2022-04-20 16:45 ` Jean-Philippe Brucker
2022-04-21 6:47 ` zhangfei.gao
2022-04-22 9:03 ` zhangfei.gao
2022-04-22 10:11 ` Jean-Philippe Brucker
2022-04-22 13:15 ` zhangfei.gao
2022-04-22 15:50 ` Jean-Philippe Brucker
2022-04-23 11:13 ` zhangfei.gao
2022-04-24 2:58 ` Zhangfei Gao
2022-04-24 9:52 ` Zhangfei Gao
2022-04-25 13:53 ` Jean-Philippe Brucker
2022-04-25 14:18 ` Dave Hansen
2022-04-25 14:26 ` Jean-Philippe Brucker
2022-04-25 15:34 ` Jacob Pan
2022-04-25 16:13 ` Jean-Philippe Brucker
2022-04-25 22:32 ` Jacob Pan
2022-04-26 4:20 ` Fenghua Yu
2022-04-26 5:04 ` Zhangfei Gao
2022-04-28 0:54 ` Fenghua Yu
2022-04-28 8:43 ` Jean-Philippe Brucker
2022-04-28 15:09 ` Dave Hansen
2022-04-28 15:28 ` Fenghua Yu
2022-04-28 15:42 ` Dave Hansen
2022-04-28 16:01 ` Jean-Philippe Brucker
2022-04-28 16:35 ` Dave Hansen
2022-04-26 4:28 ` Zhangfei Gao
2022-04-26 4:36 ` Fenghua Yu
2022-04-26 5:19 ` Zhangfei Gao
2022-04-25 15:55 ` Dave Hansen
2022-04-25 16:40 ` Jean-Philippe Brucker
2022-04-26 15:27 ` Dave Hansen
2022-04-26 16:48 ` Jean-Philippe Brucker
2022-04-26 23:31 ` Dave Hansen
2022-04-28 8:39 ` Jean-Philippe Brucker
2022-04-29 7:53 ` Baolu Lu
2022-04-29 13:51 ` Fenghua Yu
2022-04-29 14:34 ` Jean-Philippe Brucker
2022-04-29 22:19 ` Fenghua Yu
2022-04-30 7:33 ` Baolu Lu
2022-05-03 7:49 ` Jean-Philippe Brucker
2022-05-06 5:36 ` Baolu Lu
2022-04-12 14:36 ` Dave Hansen
2022-04-12 15:10 ` Jean-Philippe Brucker
2022-04-12 15:35 ` Dave Hansen
2022-04-13 11:14 ` Lu Baolu
2022-04-25 2:57 ` zhangfei.gao
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 06/11] x86/fpu: Clear PASID when copying fpstate Fenghua Yu
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 07/11] sched: Define and initialize a flag to identify valid PASID in the task Fenghua Yu
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Peter Zijlstra
2022-02-07 23:02 ` [PATCH v4 08/11] x86/traps: Demand-populate PASID MSR via #GP Fenghua Yu
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 09/11] x86/cpufeatures: Re-enable ENQCMD Fenghua Yu
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 10/11] tools/objtool: Check for use of the ENQCMD instruction in the kernel Fenghua Yu
2022-02-15 10:54 ` [tip: x86/pasid] " tip-bot2 for Fenghua Yu
2022-03-09 7:55 ` [tip: x86/core] " tip-bot2 for Fenghua Yu
2022-03-15 10:44 ` tip-bot2 for Fenghua Yu
2022-02-07 23:02 ` [PATCH v4 11/11] docs: x86: Change documentation for SVA (Shared Virtual Addressing) Fenghua Yu
2022-02-14 17:25 ` Thomas Gleixner
2022-02-15 10:54 ` [tip: x86/pasid] Documentation/x86: Update " tip-bot2 for Fenghua Yu
2022-02-11 20:04 ` [PATCH v4 00/11] Re-enable ENQCMD and PASID MSR Fenghua Yu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=tencent_CD35B6A6FBB48186B38EF641F088BAED1407@qq.com \
--to=zhangfei.gao@foxmail.com \
--cc=ashok.raj@intel.com \
--cc=bp@alien8.de \
--cc=dave.hansen@intel.com \
--cc=dave.hansen@linux.intel.com \
--cc=fenghua.yu@intel.com \
--cc=iommu@lists.linux-foundation.org \
--cc=jean-philippe@linaro.org \
--cc=joro@8bytes.org \
--cc=jpoimboe@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=ravi.v.shankar@intel.com \
--cc=tglx@linutronix.de \
--cc=tony.luck@intel.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).