* Re: [PATCH] powerpc/fault: fix wrong KUAP fault for IO_URING
From: Zorro Lang @ 2021-02-04 17:57 UTC (permalink / raw)
To: Aneesh Kumar K.V; +Cc: Jens Axboe, linuxppc-dev, Nicholas Piggin
In-Reply-To: <490cea1a-8161-2f76-03e6-7e2b16efa648@linux.ibm.com>
On Thu, Feb 04, 2021 at 10:31:59PM +0530, Aneesh Kumar K.V wrote:
> On 2/4/21 10:23 PM, Jens Axboe wrote:
> > On 2/1/21 11:30 PM, Aneesh Kumar K.V wrote:
> > > On 2/2/21 11:50 AM, Christophe Leroy wrote:
> > > >
> > > >
> > > > Le 02/02/2021 à 07:16, Aneesh Kumar K.V a écrit :
> > > > > On 2/2/21 11:32 AM, Christophe Leroy wrote:
> > > > > >
> > > > > >
> > > > > > Le 02/02/2021 à 06:55, Aneesh Kumar K.V a écrit :
> > > > > > > Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> writes:
> > > > > > >
> > > > > > > > Nicholas Piggin <npiggin@gmail.com> writes:
> > > > > > > >
> > > > > > > > > Excerpts from Michael Ellerman's message of January 30, 2021 9:22 pm:
> > > > > > > > > > Christophe Leroy <christophe.leroy@csgroup.eu> writes:
> > > > > > > > > > > +Aneesh
> > > > > > > > > > >
> > > > > > > > > > > Le 29/01/2021 à 07:52, Zorro Lang a écrit :
> > > > > > > > > > ..
> > > > > > > > > > > > [ 96.200296] ------------[ cut here ]------------
> > > > > > > > > > > > [ 96.200304] Bug: Read fault blocked by KUAP!
> > > > > > > > > > > > [ 96.200309] WARNING: CPU: 3 PID: 1876 at
> > > > > > > > > > > > arch/powerpc/mm/fault.c:229 bad_kernel_fault+0x180/0x310
> > > > > > > > > > >
> > > > > > > > > > > > [ 96.200734] NIP [c000000000849424]
> > > > > > > > > > > > fault_in_pages_readable+0x104/0x350
> > > > > > > > > > > > [ 96.200741] LR [c00000000084952c]
> > > > > > > > > > > > fault_in_pages_readable+0x20c/0x350
> > > > > > > > > > > > [ 96.200747] --- interrupt: 300
> > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > > > Problem happens in a section where userspace access is supposed
> > > > > > > > > > > to be granted, so the patch you
> > > > > > > > > > > proposed is definitely not the right fix.
> > > > > > > > > > >
> > > > > > > > > > > c000000000849408: 2c 01 00 4c isync
> > > > > > > > > > > c00000000084940c: a6 03 3d 7d mtspr 29,r9 <== granting
> > > > > > > > > > > userspace access permission
> > > > > > > > > > > c000000000849410: 2c 01 00 4c isync
> > > > > > > > > > > c000000000849414: 00 00 36 e9 ld r9,0(r22)
> > > > > > > > > > > c000000000849418: 20 00 29 81 lwz r9,32(r9)
> > > > > > > > > > > c00000000084941c: 00 02 29 71 andi. r9,r9,512
> > > > > > > > > > > c000000000849420: 78 d3 5e 7f mr r30,r26
> > > > > > > > > > > ==> c000000000849424: 00 00 bf 8b lbz r29,0(r31) <==
> > > > > > > > > > > accessing userspace
> > > > > > > > > > > c000000000849428: 10 00 82 41 beq c000000000849438
> > > > > > > > > > > <fault_in_pages_readable+0x118>
> > > > > > > > > > > c00000000084942c: 2c 01 00 4c isync
> > > > > > > > > > > c000000000849430: a6 03 bd 7e mtspr 29,r21 <==
> > > > > > > > > > > clearing userspace access permission
> > > > > > > > > > > c000000000849434: 2c 01 00 4c isync
> > > > > > > > > > >
> > > > > > > > > > > My first guess is that the problem is linked to the following
> > > > > > > > > > > function, see the comment
> > > > > > > > > > >
> > > > > > > > > > > /*
> > > > > > > > > > > * For kernel thread that doesn't have thread.regs return
> > > > > > > > > > > * default AMR/IAMR values.
> > > > > > > > > > > */
> > > > > > > > > > > static inline u64 current_thread_amr(void)
> > > > > > > > > > > {
> > > > > > > > > > > if (current->thread.regs)
> > > > > > > > > > > return current->thread.regs->amr;
> > > > > > > > > > > return AMR_KUAP_BLOCKED;
> > > > > > > > > > > }
> > > > > > > > > > >
> > > > > > > > > > > Above function was introduced by commit 48a8ab4eeb82
> > > > > > > > > > > ("powerpc/book3s64/pkeys: Don't update SPRN_AMR
> > > > > > > > > > > when in kernel mode")
> > > > > > > > > >
> > > > > > > > > > Yeah that's a bit of a curly one.
> > > > > > > > > >
> > > > > > > > > > At some point io_uring did kthread_use_mm(), which is supposed to
> > > > > > > > > > mean
> > > > > > > > > > the kthread can operate on behalf of the original process that
> > > > > > > > > > submitted
> > > > > > > > > > the IO.
> > > > > > > > > >
> > > > > > > > > > But because KUAP is implemented using memory protection keys, it
> > > > > > > > > > depends
> > > > > > > > > > on the value of the AMR register, which is not part of the mm,
> > > > > > > > > > it's in
> > > > > > > > > > thread.regs->amr.
> > > > > > > > > >
> > > > > > > > > > And what's worse by the time we're in kthread_use_mm() we no
> > > > > > > > > > longer have
> > > > > > > > > > access to the thread.regs->amr of the original process that
> > > > > > > > > > submitted
> > > > > > > > > > the IO.
> > > > > > > > > >
> > > > > > > > > > We also can't simply move the AMR into the mm, precisely because
> > > > > > > > > > it's
> > > > > > > > > > per thread, not per mm.
> > > > > > > > > >
> > > > > > > > > > So TBH I don't know how we're going to fix this.
> > > > > > > > > >
> > > > > > > > > > I guess we could return AMR=unblocked for kernel threads, but that's
> > > > > > > > > > arguably a bug because it allows a process to circumvent memory
> > > > > > > > > > keys by
> > > > > > > > > > asking the kernel to do the access.
> > > > > > > > >
> > > > > > > > > We shouldn't need to inherit AMR should we? We only need it to be
> > > > > > > > > locked
> > > > > > > > > for kernel threads until it's explicitly unlocked -- nothing mm
> > > > > > > > > specific
> > > > > > > > > there. I think current_thread_amr could return 0 for kernel
> > > > > > > > > threads? Or
> > > > > > > > > I would even avoid using that function for allow_user_access and open
> > > > > > > > > code the kthread case and remove it from current_thread_amr().
> > > > > > > > >
> > > > > > > > > Thanks,
> > > > > > > > > Nick
> > > > > > > >
> > > > > > >
> > > > > > > updated one
> > > > > > >
> > > > > > > From 8fdb0680f983940d61f91da8252b13c8d3e8ebee Mon Sep 17 00:00:00 2001
> > > > > > > From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
> > > > > > > Date: Tue, 2 Feb 2021 09:23:38 +0530
> > > > > > > Subject: [PATCH v2] powerpc/kuap: Allow kernel thread to access
> > > > > > > userspace
> > > > > > > after kthread_use_mm
> > > > > > >
> > > > > > > This fix the bad fault reported by KUAP when io_wqe_worker access
> > > > > > > userspace.
> > > > > > >
> > > > > > > Bug: Read fault blocked by KUAP!
> > > > > > > WARNING: CPU: 1 PID: 101841 at arch/powerpc/mm/fault.c:229
> > > > > > > __do_page_fault+0x6b4/0xcd0
> > > > > > > NIP [c00000000009e7e4] __do_page_fault+0x6b4/0xcd0
> > > > > > > LR [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0
> > > > > > > ..........
> > > > > > > Call Trace:
> > > > > > > [c000000016367330] [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0
> > > > > > > (unreliable)
> > > > > > > [c0000000163673e0] [c00000000009ee3c] do_page_fault+0x3c/0x120
> > > > > > > [c000000016367430] [c00000000000c848] handle_page_fault+0x10/0x2c
> > > > > > > --- interrupt: 300 at iov_iter_fault_in_readable+0x148/0x6f0
> > > > > > > ..........
> > > > > > > NIP [c0000000008e8228] iov_iter_fault_in_readable+0x148/0x6f0
> > > > > > > LR [c0000000008e834c] iov_iter_fault_in_readable+0x26c/0x6f0
> > > > > > > interrupt: 300
> > > > > > > [c0000000163677e0] [c0000000007154a0] iomap_write_actor+0xc0/0x280
> > > > > > > [c000000016367880] [c00000000070fc94] iomap_apply+0x1c4/0x780
> > > > > > > [c000000016367990] [c000000000710330]
> > > > > > > iomap_file_buffered_write+0xa0/0x120
> > > > > > > [c0000000163679e0] [c00800000040791c]
> > > > > > > xfs_file_buffered_aio_write+0x314/0x5e0 [xfs]
> > > > > > > [c000000016367a90] [c0000000006d74bc] io_write+0x10c/0x460
> > > > > > > [c000000016367bb0] [c0000000006d80e4] io_issue_sqe+0x8d4/0x1200
> > > > > > > [c000000016367c70] [c0000000006d8ad0] io_wq_submit_work+0xc0/0x250
> > > > > > > [c000000016367cb0] [c0000000006e2578]
> > > > > > > io_worker_handle_work+0x498/0x800
> > > > > > > [c000000016367d40] [c0000000006e2cdc] io_wqe_worker+0x3fc/0x4f0
> > > > > > > [c000000016367da0] [c0000000001cb0a4] kthread+0x1c4/0x1d0
> > > > > > > [c000000016367e10] [c00000000000dbf0]
> > > > > > > ret_from_kernel_thread+0x5c/0x6c
> > > > > > >
> > > > > > > The kernel consider thread AMR value for kernel thread to be
> > > > > > > AMR_KUAP_BLOCKED. Hence access to userspace is denied. This
> > > > > > > of course not correct and we should allow userspace access after
> > > > > > > kthread_use_mm(). To be precise, kthread_use_mm() should inherit the
> > > > > > > AMR value of the operating address space. But, the AMR value is
> > > > > > > thread-specific and we inherit the address space and not thread
> > > > > > > access restrictions. Because of this ignore AMR value when accessing
> > > > > > > userspace via kernel thread.
> > > > > > >
> > > > > > > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
> > > > > > > ---
> > > > > > > Changes from v1:
> > > > > > > * Address review feedback from Nick
> > > > > > >
> > > > > > > arch/powerpc/include/asm/book3s/64/kup.h | 8 +++++++-
> > > > > > > 1 file changed, 7 insertions(+), 1 deletion(-)
> > > > > > >
> > > > > > > diff --git a/arch/powerpc/include/asm/book3s/64/kup.h
> > > > > > > b/arch/powerpc/include/asm/book3s/64/kup.h
> > > > > > > index f50f72e535aa..95f4df99249e 100644
> > > > > > > --- a/arch/powerpc/include/asm/book3s/64/kup.h
> > > > > > > +++ b/arch/powerpc/include/asm/book3s/64/kup.h
> > > > > > > @@ -384,7 +384,13 @@ static __always_inline void
> > > > > > > allow_user_access(void __user *to, const void __user
> > > > > > > // This is written so we can resolve to a single case at build
> > > > > > > time
> > > > > > > BUILD_BUG_ON(!__builtin_constant_p(dir));
> > > > > > > - if (mmu_has_feature(MMU_FTR_PKEY))
> > > > > > > + /*
> > > > > > > + * if it is a kthread that did kthread_use_mm() don't
> > > > > > > + * use current_thread_amr().
> > > > > >
> > > > > > According to include/linux/sched.h, PF_KTHREAD means /* I am a kernel
> > > > > > thread */
> > > > > > It doesn't seem to be related to kthread_use_mm()
> > > > >
> > > > > That should be a sufficient check here. if we did reach here without
> > > > > calling kthread_user_mm, we will crash on access because we don't have
> > > > > a mm attached to the current process. a kernel thread with
> > > > > kthread_use_mm has
> > > >
> > > > Ok but then the comment doesn't match the check.
> > >
> > >
> > > I was trying to be explict in the comment that we expect the thread to
> > > have done kthread_use_mm().
> > >
> > > >
> > > > And also the comment in current_thread_amr() is then misleading.
> > > >
> > > > Why not do the current->flags & PF_KTHREAD check in current_thread_amr()
> > > > and return 0 in that case instead of BLOCKED ?
> > >
> > > In my view currrent_thread_amr() is more generic and we want to be
> > > explicit there that a kernel thread AMR is KUAP_BLOCKED. Only when we
> > > call allow user access, we relax the AMR value.
> >
> > Just following up on this, as I'd hate to have 5.11 released with this
> > bug in it for powerpc. It'll obviously also affect other cases of a
> > kernel thread faulting after having done kthread_use_mm(), though I'm
> > not sure how widespread that is. In any case, it'll leave io_uring
> > mostly broken on powerpc if this isn't patched for release.
> >
>
> I am waiting for test feedback on the change I posted earlier. I am also
> running a regression run myself. Once that is complete i will post the patch
> as a separate email.
Are you waiting a test from me? Or someone else who test PPC? Although I'm
the "Reported-by" of this bug, I just can help to verify this bug itself,
I don't have enough test cases to do regression test from PPC side. Do you need
me to verify this bug itself.
Thanks,
Zorro
>
> -aneesh
>
^ permalink raw reply
* Re: [PATCH] powerpc/fault: fix wrong KUAP fault for IO_URING
From: Jens Axboe @ 2021-02-04 17:03 UTC (permalink / raw)
To: Aneesh Kumar K.V, Christophe Leroy, Nicholas Piggin,
Michael Ellerman, Zorro Lang
Cc: linuxppc-dev
In-Reply-To: <490cea1a-8161-2f76-03e6-7e2b16efa648@linux.ibm.com>
On 2/4/21 10:01 AM, Aneesh Kumar K.V wrote:
> On 2/4/21 10:23 PM, Jens Axboe wrote:
>> On 2/1/21 11:30 PM, Aneesh Kumar K.V wrote:
>>> On 2/2/21 11:50 AM, Christophe Leroy wrote:
>>>>
>>>>
>>>> Le 02/02/2021 à 07:16, Aneesh Kumar K.V a écrit :
>>>>> On 2/2/21 11:32 AM, Christophe Leroy wrote:
>>>>>>
>>>>>>
>>>>>> Le 02/02/2021 à 06:55, Aneesh Kumar K.V a écrit :
>>>>>>> Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> writes:
>>>>>>>
>>>>>>>> Nicholas Piggin <npiggin@gmail.com> writes:
>>>>>>>>
>>>>>>>>> Excerpts from Michael Ellerman's message of January 30, 2021 9:22 pm:
>>>>>>>>>> Christophe Leroy <christophe.leroy@csgroup.eu> writes:
>>>>>>>>>>> +Aneesh
>>>>>>>>>>>
>>>>>>>>>>> Le 29/01/2021 à 07:52, Zorro Lang a écrit :
>>>>>>>>>> ..
>>>>>>>>>>>> [ 96.200296] ------------[ cut here ]------------
>>>>>>>>>>>> [ 96.200304] Bug: Read fault blocked by KUAP!
>>>>>>>>>>>> [ 96.200309] WARNING: CPU: 3 PID: 1876 at
>>>>>>>>>>>> arch/powerpc/mm/fault.c:229 bad_kernel_fault+0x180/0x310
>>>>>>>>>>>
>>>>>>>>>>>> [ 96.200734] NIP [c000000000849424]
>>>>>>>>>>>> fault_in_pages_readable+0x104/0x350
>>>>>>>>>>>> [ 96.200741] LR [c00000000084952c]
>>>>>>>>>>>> fault_in_pages_readable+0x20c/0x350
>>>>>>>>>>>> [ 96.200747] --- interrupt: 300
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Problem happens in a section where userspace access is supposed
>>>>>>>>>>> to be granted, so the patch you
>>>>>>>>>>> proposed is definitely not the right fix.
>>>>>>>>>>>
>>>>>>>>>>> c000000000849408: 2c 01 00 4c isync
>>>>>>>>>>> c00000000084940c: a6 03 3d 7d mtspr 29,r9 <== granting
>>>>>>>>>>> userspace access permission
>>>>>>>>>>> c000000000849410: 2c 01 00 4c isync
>>>>>>>>>>> c000000000849414: 00 00 36 e9 ld r9,0(r22)
>>>>>>>>>>> c000000000849418: 20 00 29 81 lwz r9,32(r9)
>>>>>>>>>>> c00000000084941c: 00 02 29 71 andi. r9,r9,512
>>>>>>>>>>> c000000000849420: 78 d3 5e 7f mr r30,r26
>>>>>>>>>>> ==> c000000000849424: 00 00 bf 8b lbz r29,0(r31) <==
>>>>>>>>>>> accessing userspace
>>>>>>>>>>> c000000000849428: 10 00 82 41 beq c000000000849438
>>>>>>>>>>> <fault_in_pages_readable+0x118>
>>>>>>>>>>> c00000000084942c: 2c 01 00 4c isync
>>>>>>>>>>> c000000000849430: a6 03 bd 7e mtspr 29,r21 <==
>>>>>>>>>>> clearing userspace access permission
>>>>>>>>>>> c000000000849434: 2c 01 00 4c isync
>>>>>>>>>>>
>>>>>>>>>>> My first guess is that the problem is linked to the following
>>>>>>>>>>> function, see the comment
>>>>>>>>>>>
>>>>>>>>>>> /*
>>>>>>>>>>> * For kernel thread that doesn't have thread.regs return
>>>>>>>>>>> * default AMR/IAMR values.
>>>>>>>>>>> */
>>>>>>>>>>> static inline u64 current_thread_amr(void)
>>>>>>>>>>> {
>>>>>>>>>>> if (current->thread.regs)
>>>>>>>>>>> return current->thread.regs->amr;
>>>>>>>>>>> return AMR_KUAP_BLOCKED;
>>>>>>>>>>> }
>>>>>>>>>>>
>>>>>>>>>>> Above function was introduced by commit 48a8ab4eeb82
>>>>>>>>>>> ("powerpc/book3s64/pkeys: Don't update SPRN_AMR
>>>>>>>>>>> when in kernel mode")
>>>>>>>>>>
>>>>>>>>>> Yeah that's a bit of a curly one.
>>>>>>>>>>
>>>>>>>>>> At some point io_uring did kthread_use_mm(), which is supposed to
>>>>>>>>>> mean
>>>>>>>>>> the kthread can operate on behalf of the original process that
>>>>>>>>>> submitted
>>>>>>>>>> the IO.
>>>>>>>>>>
>>>>>>>>>> But because KUAP is implemented using memory protection keys, it
>>>>>>>>>> depends
>>>>>>>>>> on the value of the AMR register, which is not part of the mm,
>>>>>>>>>> it's in
>>>>>>>>>> thread.regs->amr.
>>>>>>>>>>
>>>>>>>>>> And what's worse by the time we're in kthread_use_mm() we no
>>>>>>>>>> longer have
>>>>>>>>>> access to the thread.regs->amr of the original process that
>>>>>>>>>> submitted
>>>>>>>>>> the IO.
>>>>>>>>>>
>>>>>>>>>> We also can't simply move the AMR into the mm, precisely because
>>>>>>>>>> it's
>>>>>>>>>> per thread, not per mm.
>>>>>>>>>>
>>>>>>>>>> So TBH I don't know how we're going to fix this.
>>>>>>>>>>
>>>>>>>>>> I guess we could return AMR=unblocked for kernel threads, but that's
>>>>>>>>>> arguably a bug because it allows a process to circumvent memory
>>>>>>>>>> keys by
>>>>>>>>>> asking the kernel to do the access.
>>>>>>>>>
>>>>>>>>> We shouldn't need to inherit AMR should we? We only need it to be
>>>>>>>>> locked
>>>>>>>>> for kernel threads until it's explicitly unlocked -- nothing mm
>>>>>>>>> specific
>>>>>>>>> there. I think current_thread_amr could return 0 for kernel
>>>>>>>>> threads? Or
>>>>>>>>> I would even avoid using that function for allow_user_access and open
>>>>>>>>> code the kthread case and remove it from current_thread_amr().
>>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>> Nick
>>>>>>>>
>>>>>>>
>>>>>>> updated one
>>>>>>>
>>>>>>> From 8fdb0680f983940d61f91da8252b13c8d3e8ebee Mon Sep 17 00:00:00 2001
>>>>>>> From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
>>>>>>> Date: Tue, 2 Feb 2021 09:23:38 +0530
>>>>>>> Subject: [PATCH v2] powerpc/kuap: Allow kernel thread to access
>>>>>>> userspace
>>>>>>> after kthread_use_mm
>>>>>>>
>>>>>>> This fix the bad fault reported by KUAP when io_wqe_worker access
>>>>>>> userspace.
>>>>>>>
>>>>>>> Bug: Read fault blocked by KUAP!
>>>>>>> WARNING: CPU: 1 PID: 101841 at arch/powerpc/mm/fault.c:229
>>>>>>> __do_page_fault+0x6b4/0xcd0
>>>>>>> NIP [c00000000009e7e4] __do_page_fault+0x6b4/0xcd0
>>>>>>> LR [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0
>>>>>>> ..........
>>>>>>> Call Trace:
>>>>>>> [c000000016367330] [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0
>>>>>>> (unreliable)
>>>>>>> [c0000000163673e0] [c00000000009ee3c] do_page_fault+0x3c/0x120
>>>>>>> [c000000016367430] [c00000000000c848] handle_page_fault+0x10/0x2c
>>>>>>> --- interrupt: 300 at iov_iter_fault_in_readable+0x148/0x6f0
>>>>>>> ..........
>>>>>>> NIP [c0000000008e8228] iov_iter_fault_in_readable+0x148/0x6f0
>>>>>>> LR [c0000000008e834c] iov_iter_fault_in_readable+0x26c/0x6f0
>>>>>>> interrupt: 300
>>>>>>> [c0000000163677e0] [c0000000007154a0] iomap_write_actor+0xc0/0x280
>>>>>>> [c000000016367880] [c00000000070fc94] iomap_apply+0x1c4/0x780
>>>>>>> [c000000016367990] [c000000000710330]
>>>>>>> iomap_file_buffered_write+0xa0/0x120
>>>>>>> [c0000000163679e0] [c00800000040791c]
>>>>>>> xfs_file_buffered_aio_write+0x314/0x5e0 [xfs]
>>>>>>> [c000000016367a90] [c0000000006d74bc] io_write+0x10c/0x460
>>>>>>> [c000000016367bb0] [c0000000006d80e4] io_issue_sqe+0x8d4/0x1200
>>>>>>> [c000000016367c70] [c0000000006d8ad0] io_wq_submit_work+0xc0/0x250
>>>>>>> [c000000016367cb0] [c0000000006e2578]
>>>>>>> io_worker_handle_work+0x498/0x800
>>>>>>> [c000000016367d40] [c0000000006e2cdc] io_wqe_worker+0x3fc/0x4f0
>>>>>>> [c000000016367da0] [c0000000001cb0a4] kthread+0x1c4/0x1d0
>>>>>>> [c000000016367e10] [c00000000000dbf0]
>>>>>>> ret_from_kernel_thread+0x5c/0x6c
>>>>>>>
>>>>>>> The kernel consider thread AMR value for kernel thread to be
>>>>>>> AMR_KUAP_BLOCKED. Hence access to userspace is denied. This
>>>>>>> of course not correct and we should allow userspace access after
>>>>>>> kthread_use_mm(). To be precise, kthread_use_mm() should inherit the
>>>>>>> AMR value of the operating address space. But, the AMR value is
>>>>>>> thread-specific and we inherit the address space and not thread
>>>>>>> access restrictions. Because of this ignore AMR value when accessing
>>>>>>> userspace via kernel thread.
>>>>>>>
>>>>>>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
>>>>>>> ---
>>>>>>> Changes from v1:
>>>>>>> * Address review feedback from Nick
>>>>>>>
>>>>>>> arch/powerpc/include/asm/book3s/64/kup.h | 8 +++++++-
>>>>>>> 1 file changed, 7 insertions(+), 1 deletion(-)
>>>>>>>
>>>>>>> diff --git a/arch/powerpc/include/asm/book3s/64/kup.h
>>>>>>> b/arch/powerpc/include/asm/book3s/64/kup.h
>>>>>>> index f50f72e535aa..95f4df99249e 100644
>>>>>>> --- a/arch/powerpc/include/asm/book3s/64/kup.h
>>>>>>> +++ b/arch/powerpc/include/asm/book3s/64/kup.h
>>>>>>> @@ -384,7 +384,13 @@ static __always_inline void
>>>>>>> allow_user_access(void __user *to, const void __user
>>>>>>> // This is written so we can resolve to a single case at build
>>>>>>> time
>>>>>>> BUILD_BUG_ON(!__builtin_constant_p(dir));
>>>>>>> - if (mmu_has_feature(MMU_FTR_PKEY))
>>>>>>> + /*
>>>>>>> + * if it is a kthread that did kthread_use_mm() don't
>>>>>>> + * use current_thread_amr().
>>>>>>
>>>>>> According to include/linux/sched.h, PF_KTHREAD means /* I am a kernel
>>>>>> thread */
>>>>>> It doesn't seem to be related to kthread_use_mm()
>>>>>
>>>>> That should be a sufficient check here. if we did reach here without
>>>>> calling kthread_user_mm, we will crash on access because we don't have
>>>>> a mm attached to the current process. a kernel thread with
>>>>> kthread_use_mm has
>>>>
>>>> Ok but then the comment doesn't match the check.
>>>
>>>
>>> I was trying to be explict in the comment that we expect the thread to
>>> have done kthread_use_mm().
>>>
>>>>
>>>> And also the comment in current_thread_amr() is then misleading.
>>>>
>>>> Why not do the current->flags & PF_KTHREAD check in current_thread_amr()
>>>> and return 0 in that case instead of BLOCKED ?
>>>
>>> In my view currrent_thread_amr() is more generic and we want to be
>>> explicit there that a kernel thread AMR is KUAP_BLOCKED. Only when we
>>> call allow user access, we relax the AMR value.
>>
>> Just following up on this, as I'd hate to have 5.11 released with this
>> bug in it for powerpc. It'll obviously also affect other cases of a
>> kernel thread faulting after having done kthread_use_mm(), though I'm
>> not sure how widespread that is. In any case, it'll leave io_uring
>> mostly broken on powerpc if this isn't patched for release.
>>
>
> I am waiting for test feedback on the change I posted earlier. I am also
> running a regression run myself. Once that is complete i will post the
> patch as a separate email.
Perfect, sounds good!
--
Jens Axboe
^ permalink raw reply
* Re: [PATCH] powerpc/fault: fix wrong KUAP fault for IO_URING
From: Aneesh Kumar K.V @ 2021-02-04 17:01 UTC (permalink / raw)
To: Jens Axboe, Christophe Leroy, Nicholas Piggin, Michael Ellerman,
Zorro Lang
Cc: linuxppc-dev
In-Reply-To: <086f6525-b851-c4c0-d611-42f76a54a2d9@kernel.dk>
On 2/4/21 10:23 PM, Jens Axboe wrote:
> On 2/1/21 11:30 PM, Aneesh Kumar K.V wrote:
>> On 2/2/21 11:50 AM, Christophe Leroy wrote:
>>>
>>>
>>> Le 02/02/2021 à 07:16, Aneesh Kumar K.V a écrit :
>>>> On 2/2/21 11:32 AM, Christophe Leroy wrote:
>>>>>
>>>>>
>>>>> Le 02/02/2021 à 06:55, Aneesh Kumar K.V a écrit :
>>>>>> Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> writes:
>>>>>>
>>>>>>> Nicholas Piggin <npiggin@gmail.com> writes:
>>>>>>>
>>>>>>>> Excerpts from Michael Ellerman's message of January 30, 2021 9:22 pm:
>>>>>>>>> Christophe Leroy <christophe.leroy@csgroup.eu> writes:
>>>>>>>>>> +Aneesh
>>>>>>>>>>
>>>>>>>>>> Le 29/01/2021 à 07:52, Zorro Lang a écrit :
>>>>>>>>> ..
>>>>>>>>>>> [ 96.200296] ------------[ cut here ]------------
>>>>>>>>>>> [ 96.200304] Bug: Read fault blocked by KUAP!
>>>>>>>>>>> [ 96.200309] WARNING: CPU: 3 PID: 1876 at
>>>>>>>>>>> arch/powerpc/mm/fault.c:229 bad_kernel_fault+0x180/0x310
>>>>>>>>>>
>>>>>>>>>>> [ 96.200734] NIP [c000000000849424]
>>>>>>>>>>> fault_in_pages_readable+0x104/0x350
>>>>>>>>>>> [ 96.200741] LR [c00000000084952c]
>>>>>>>>>>> fault_in_pages_readable+0x20c/0x350
>>>>>>>>>>> [ 96.200747] --- interrupt: 300
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Problem happens in a section where userspace access is supposed
>>>>>>>>>> to be granted, so the patch you
>>>>>>>>>> proposed is definitely not the right fix.
>>>>>>>>>>
>>>>>>>>>> c000000000849408: 2c 01 00 4c isync
>>>>>>>>>> c00000000084940c: a6 03 3d 7d mtspr 29,r9 <== granting
>>>>>>>>>> userspace access permission
>>>>>>>>>> c000000000849410: 2c 01 00 4c isync
>>>>>>>>>> c000000000849414: 00 00 36 e9 ld r9,0(r22)
>>>>>>>>>> c000000000849418: 20 00 29 81 lwz r9,32(r9)
>>>>>>>>>> c00000000084941c: 00 02 29 71 andi. r9,r9,512
>>>>>>>>>> c000000000849420: 78 d3 5e 7f mr r30,r26
>>>>>>>>>> ==> c000000000849424: 00 00 bf 8b lbz r29,0(r31) <==
>>>>>>>>>> accessing userspace
>>>>>>>>>> c000000000849428: 10 00 82 41 beq c000000000849438
>>>>>>>>>> <fault_in_pages_readable+0x118>
>>>>>>>>>> c00000000084942c: 2c 01 00 4c isync
>>>>>>>>>> c000000000849430: a6 03 bd 7e mtspr 29,r21 <==
>>>>>>>>>> clearing userspace access permission
>>>>>>>>>> c000000000849434: 2c 01 00 4c isync
>>>>>>>>>>
>>>>>>>>>> My first guess is that the problem is linked to the following
>>>>>>>>>> function, see the comment
>>>>>>>>>>
>>>>>>>>>> /*
>>>>>>>>>> * For kernel thread that doesn't have thread.regs return
>>>>>>>>>> * default AMR/IAMR values.
>>>>>>>>>> */
>>>>>>>>>> static inline u64 current_thread_amr(void)
>>>>>>>>>> {
>>>>>>>>>> if (current->thread.regs)
>>>>>>>>>> return current->thread.regs->amr;
>>>>>>>>>> return AMR_KUAP_BLOCKED;
>>>>>>>>>> }
>>>>>>>>>>
>>>>>>>>>> Above function was introduced by commit 48a8ab4eeb82
>>>>>>>>>> ("powerpc/book3s64/pkeys: Don't update SPRN_AMR
>>>>>>>>>> when in kernel mode")
>>>>>>>>>
>>>>>>>>> Yeah that's a bit of a curly one.
>>>>>>>>>
>>>>>>>>> At some point io_uring did kthread_use_mm(), which is supposed to
>>>>>>>>> mean
>>>>>>>>> the kthread can operate on behalf of the original process that
>>>>>>>>> submitted
>>>>>>>>> the IO.
>>>>>>>>>
>>>>>>>>> But because KUAP is implemented using memory protection keys, it
>>>>>>>>> depends
>>>>>>>>> on the value of the AMR register, which is not part of the mm,
>>>>>>>>> it's in
>>>>>>>>> thread.regs->amr.
>>>>>>>>>
>>>>>>>>> And what's worse by the time we're in kthread_use_mm() we no
>>>>>>>>> longer have
>>>>>>>>> access to the thread.regs->amr of the original process that
>>>>>>>>> submitted
>>>>>>>>> the IO.
>>>>>>>>>
>>>>>>>>> We also can't simply move the AMR into the mm, precisely because
>>>>>>>>> it's
>>>>>>>>> per thread, not per mm.
>>>>>>>>>
>>>>>>>>> So TBH I don't know how we're going to fix this.
>>>>>>>>>
>>>>>>>>> I guess we could return AMR=unblocked for kernel threads, but that's
>>>>>>>>> arguably a bug because it allows a process to circumvent memory
>>>>>>>>> keys by
>>>>>>>>> asking the kernel to do the access.
>>>>>>>>
>>>>>>>> We shouldn't need to inherit AMR should we? We only need it to be
>>>>>>>> locked
>>>>>>>> for kernel threads until it's explicitly unlocked -- nothing mm
>>>>>>>> specific
>>>>>>>> there. I think current_thread_amr could return 0 for kernel
>>>>>>>> threads? Or
>>>>>>>> I would even avoid using that function for allow_user_access and open
>>>>>>>> code the kthread case and remove it from current_thread_amr().
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>> Nick
>>>>>>>
>>>>>>
>>>>>> updated one
>>>>>>
>>>>>> From 8fdb0680f983940d61f91da8252b13c8d3e8ebee Mon Sep 17 00:00:00 2001
>>>>>> From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
>>>>>> Date: Tue, 2 Feb 2021 09:23:38 +0530
>>>>>> Subject: [PATCH v2] powerpc/kuap: Allow kernel thread to access
>>>>>> userspace
>>>>>> after kthread_use_mm
>>>>>>
>>>>>> This fix the bad fault reported by KUAP when io_wqe_worker access
>>>>>> userspace.
>>>>>>
>>>>>> Bug: Read fault blocked by KUAP!
>>>>>> WARNING: CPU: 1 PID: 101841 at arch/powerpc/mm/fault.c:229
>>>>>> __do_page_fault+0x6b4/0xcd0
>>>>>> NIP [c00000000009e7e4] __do_page_fault+0x6b4/0xcd0
>>>>>> LR [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0
>>>>>> ..........
>>>>>> Call Trace:
>>>>>> [c000000016367330] [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0
>>>>>> (unreliable)
>>>>>> [c0000000163673e0] [c00000000009ee3c] do_page_fault+0x3c/0x120
>>>>>> [c000000016367430] [c00000000000c848] handle_page_fault+0x10/0x2c
>>>>>> --- interrupt: 300 at iov_iter_fault_in_readable+0x148/0x6f0
>>>>>> ..........
>>>>>> NIP [c0000000008e8228] iov_iter_fault_in_readable+0x148/0x6f0
>>>>>> LR [c0000000008e834c] iov_iter_fault_in_readable+0x26c/0x6f0
>>>>>> interrupt: 300
>>>>>> [c0000000163677e0] [c0000000007154a0] iomap_write_actor+0xc0/0x280
>>>>>> [c000000016367880] [c00000000070fc94] iomap_apply+0x1c4/0x780
>>>>>> [c000000016367990] [c000000000710330]
>>>>>> iomap_file_buffered_write+0xa0/0x120
>>>>>> [c0000000163679e0] [c00800000040791c]
>>>>>> xfs_file_buffered_aio_write+0x314/0x5e0 [xfs]
>>>>>> [c000000016367a90] [c0000000006d74bc] io_write+0x10c/0x460
>>>>>> [c000000016367bb0] [c0000000006d80e4] io_issue_sqe+0x8d4/0x1200
>>>>>> [c000000016367c70] [c0000000006d8ad0] io_wq_submit_work+0xc0/0x250
>>>>>> [c000000016367cb0] [c0000000006e2578]
>>>>>> io_worker_handle_work+0x498/0x800
>>>>>> [c000000016367d40] [c0000000006e2cdc] io_wqe_worker+0x3fc/0x4f0
>>>>>> [c000000016367da0] [c0000000001cb0a4] kthread+0x1c4/0x1d0
>>>>>> [c000000016367e10] [c00000000000dbf0]
>>>>>> ret_from_kernel_thread+0x5c/0x6c
>>>>>>
>>>>>> The kernel consider thread AMR value for kernel thread to be
>>>>>> AMR_KUAP_BLOCKED. Hence access to userspace is denied. This
>>>>>> of course not correct and we should allow userspace access after
>>>>>> kthread_use_mm(). To be precise, kthread_use_mm() should inherit the
>>>>>> AMR value of the operating address space. But, the AMR value is
>>>>>> thread-specific and we inherit the address space and not thread
>>>>>> access restrictions. Because of this ignore AMR value when accessing
>>>>>> userspace via kernel thread.
>>>>>>
>>>>>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
>>>>>> ---
>>>>>> Changes from v1:
>>>>>> * Address review feedback from Nick
>>>>>>
>>>>>> arch/powerpc/include/asm/book3s/64/kup.h | 8 +++++++-
>>>>>> 1 file changed, 7 insertions(+), 1 deletion(-)
>>>>>>
>>>>>> diff --git a/arch/powerpc/include/asm/book3s/64/kup.h
>>>>>> b/arch/powerpc/include/asm/book3s/64/kup.h
>>>>>> index f50f72e535aa..95f4df99249e 100644
>>>>>> --- a/arch/powerpc/include/asm/book3s/64/kup.h
>>>>>> +++ b/arch/powerpc/include/asm/book3s/64/kup.h
>>>>>> @@ -384,7 +384,13 @@ static __always_inline void
>>>>>> allow_user_access(void __user *to, const void __user
>>>>>> // This is written so we can resolve to a single case at build
>>>>>> time
>>>>>> BUILD_BUG_ON(!__builtin_constant_p(dir));
>>>>>> - if (mmu_has_feature(MMU_FTR_PKEY))
>>>>>> + /*
>>>>>> + * if it is a kthread that did kthread_use_mm() don't
>>>>>> + * use current_thread_amr().
>>>>>
>>>>> According to include/linux/sched.h, PF_KTHREAD means /* I am a kernel
>>>>> thread */
>>>>> It doesn't seem to be related to kthread_use_mm()
>>>>
>>>> That should be a sufficient check here. if we did reach here without
>>>> calling kthread_user_mm, we will crash on access because we don't have
>>>> a mm attached to the current process. a kernel thread with
>>>> kthread_use_mm has
>>>
>>> Ok but then the comment doesn't match the check.
>>
>>
>> I was trying to be explict in the comment that we expect the thread to
>> have done kthread_use_mm().
>>
>>>
>>> And also the comment in current_thread_amr() is then misleading.
>>>
>>> Why not do the current->flags & PF_KTHREAD check in current_thread_amr()
>>> and return 0 in that case instead of BLOCKED ?
>>
>> In my view currrent_thread_amr() is more generic and we want to be
>> explicit there that a kernel thread AMR is KUAP_BLOCKED. Only when we
>> call allow user access, we relax the AMR value.
>
> Just following up on this, as I'd hate to have 5.11 released with this
> bug in it for powerpc. It'll obviously also affect other cases of a
> kernel thread faulting after having done kthread_use_mm(), though I'm
> not sure how widespread that is. In any case, it'll leave io_uring
> mostly broken on powerpc if this isn't patched for release.
>
I am waiting for test feedback on the change I posted earlier. I am also
running a regression run myself. Once that is complete i will post the
patch as a separate email.
-aneesh
^ permalink raw reply
* Re: [PATCH] powerpc/fault: fix wrong KUAP fault for IO_URING
From: Jens Axboe @ 2021-02-04 16:53 UTC (permalink / raw)
To: Aneesh Kumar K.V, Christophe Leroy, Nicholas Piggin,
Michael Ellerman, Zorro Lang
Cc: linuxppc-dev
In-Reply-To: <e2dfb7ec-a4d4-579d-a79b-6709df6e9e50@linux.ibm.com>
On 2/1/21 11:30 PM, Aneesh Kumar K.V wrote:
> On 2/2/21 11:50 AM, Christophe Leroy wrote:
>>
>>
>> Le 02/02/2021 à 07:16, Aneesh Kumar K.V a écrit :
>>> On 2/2/21 11:32 AM, Christophe Leroy wrote:
>>>>
>>>>
>>>> Le 02/02/2021 à 06:55, Aneesh Kumar K.V a écrit :
>>>>> Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> writes:
>>>>>
>>>>>> Nicholas Piggin <npiggin@gmail.com> writes:
>>>>>>
>>>>>>> Excerpts from Michael Ellerman's message of January 30, 2021 9:22 pm:
>>>>>>>> Christophe Leroy <christophe.leroy@csgroup.eu> writes:
>>>>>>>>> +Aneesh
>>>>>>>>>
>>>>>>>>> Le 29/01/2021 à 07:52, Zorro Lang a écrit :
>>>>>>>> ..
>>>>>>>>>> [ 96.200296] ------------[ cut here ]------------
>>>>>>>>>> [ 96.200304] Bug: Read fault blocked by KUAP!
>>>>>>>>>> [ 96.200309] WARNING: CPU: 3 PID: 1876 at
>>>>>>>>>> arch/powerpc/mm/fault.c:229 bad_kernel_fault+0x180/0x310
>>>>>>>>>
>>>>>>>>>> [ 96.200734] NIP [c000000000849424]
>>>>>>>>>> fault_in_pages_readable+0x104/0x350
>>>>>>>>>> [ 96.200741] LR [c00000000084952c]
>>>>>>>>>> fault_in_pages_readable+0x20c/0x350
>>>>>>>>>> [ 96.200747] --- interrupt: 300
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Problem happens in a section where userspace access is supposed
>>>>>>>>> to be granted, so the patch you
>>>>>>>>> proposed is definitely not the right fix.
>>>>>>>>>
>>>>>>>>> c000000000849408: 2c 01 00 4c isync
>>>>>>>>> c00000000084940c: a6 03 3d 7d mtspr 29,r9 <== granting
>>>>>>>>> userspace access permission
>>>>>>>>> c000000000849410: 2c 01 00 4c isync
>>>>>>>>> c000000000849414: 00 00 36 e9 ld r9,0(r22)
>>>>>>>>> c000000000849418: 20 00 29 81 lwz r9,32(r9)
>>>>>>>>> c00000000084941c: 00 02 29 71 andi. r9,r9,512
>>>>>>>>> c000000000849420: 78 d3 5e 7f mr r30,r26
>>>>>>>>> ==> c000000000849424: 00 00 bf 8b lbz r29,0(r31) <==
>>>>>>>>> accessing userspace
>>>>>>>>> c000000000849428: 10 00 82 41 beq c000000000849438
>>>>>>>>> <fault_in_pages_readable+0x118>
>>>>>>>>> c00000000084942c: 2c 01 00 4c isync
>>>>>>>>> c000000000849430: a6 03 bd 7e mtspr 29,r21 <==
>>>>>>>>> clearing userspace access permission
>>>>>>>>> c000000000849434: 2c 01 00 4c isync
>>>>>>>>>
>>>>>>>>> My first guess is that the problem is linked to the following
>>>>>>>>> function, see the comment
>>>>>>>>>
>>>>>>>>> /*
>>>>>>>>> * For kernel thread that doesn't have thread.regs return
>>>>>>>>> * default AMR/IAMR values.
>>>>>>>>> */
>>>>>>>>> static inline u64 current_thread_amr(void)
>>>>>>>>> {
>>>>>>>>> if (current->thread.regs)
>>>>>>>>> return current->thread.regs->amr;
>>>>>>>>> return AMR_KUAP_BLOCKED;
>>>>>>>>> }
>>>>>>>>>
>>>>>>>>> Above function was introduced by commit 48a8ab4eeb82
>>>>>>>>> ("powerpc/book3s64/pkeys: Don't update SPRN_AMR
>>>>>>>>> when in kernel mode")
>>>>>>>>
>>>>>>>> Yeah that's a bit of a curly one.
>>>>>>>>
>>>>>>>> At some point io_uring did kthread_use_mm(), which is supposed to
>>>>>>>> mean
>>>>>>>> the kthread can operate on behalf of the original process that
>>>>>>>> submitted
>>>>>>>> the IO.
>>>>>>>>
>>>>>>>> But because KUAP is implemented using memory protection keys, it
>>>>>>>> depends
>>>>>>>> on the value of the AMR register, which is not part of the mm,
>>>>>>>> it's in
>>>>>>>> thread.regs->amr.
>>>>>>>>
>>>>>>>> And what's worse by the time we're in kthread_use_mm() we no
>>>>>>>> longer have
>>>>>>>> access to the thread.regs->amr of the original process that
>>>>>>>> submitted
>>>>>>>> the IO.
>>>>>>>>
>>>>>>>> We also can't simply move the AMR into the mm, precisely because
>>>>>>>> it's
>>>>>>>> per thread, not per mm.
>>>>>>>>
>>>>>>>> So TBH I don't know how we're going to fix this.
>>>>>>>>
>>>>>>>> I guess we could return AMR=unblocked for kernel threads, but that's
>>>>>>>> arguably a bug because it allows a process to circumvent memory
>>>>>>>> keys by
>>>>>>>> asking the kernel to do the access.
>>>>>>>
>>>>>>> We shouldn't need to inherit AMR should we? We only need it to be
>>>>>>> locked
>>>>>>> for kernel threads until it's explicitly unlocked -- nothing mm
>>>>>>> specific
>>>>>>> there. I think current_thread_amr could return 0 for kernel
>>>>>>> threads? Or
>>>>>>> I would even avoid using that function for allow_user_access and open
>>>>>>> code the kthread case and remove it from current_thread_amr().
>>>>>>>
>>>>>>> Thanks,
>>>>>>> Nick
>>>>>>
>>>>>
>>>>> updated one
>>>>>
>>>>> From 8fdb0680f983940d61f91da8252b13c8d3e8ebee Mon Sep 17 00:00:00 2001
>>>>> From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
>>>>> Date: Tue, 2 Feb 2021 09:23:38 +0530
>>>>> Subject: [PATCH v2] powerpc/kuap: Allow kernel thread to access
>>>>> userspace
>>>>> after kthread_use_mm
>>>>>
>>>>> This fix the bad fault reported by KUAP when io_wqe_worker access
>>>>> userspace.
>>>>>
>>>>> Bug: Read fault blocked by KUAP!
>>>>> WARNING: CPU: 1 PID: 101841 at arch/powerpc/mm/fault.c:229
>>>>> __do_page_fault+0x6b4/0xcd0
>>>>> NIP [c00000000009e7e4] __do_page_fault+0x6b4/0xcd0
>>>>> LR [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0
>>>>> ..........
>>>>> Call Trace:
>>>>> [c000000016367330] [c00000000009e7e0] __do_page_fault+0x6b0/0xcd0
>>>>> (unreliable)
>>>>> [c0000000163673e0] [c00000000009ee3c] do_page_fault+0x3c/0x120
>>>>> [c000000016367430] [c00000000000c848] handle_page_fault+0x10/0x2c
>>>>> --- interrupt: 300 at iov_iter_fault_in_readable+0x148/0x6f0
>>>>> ..........
>>>>> NIP [c0000000008e8228] iov_iter_fault_in_readable+0x148/0x6f0
>>>>> LR [c0000000008e834c] iov_iter_fault_in_readable+0x26c/0x6f0
>>>>> interrupt: 300
>>>>> [c0000000163677e0] [c0000000007154a0] iomap_write_actor+0xc0/0x280
>>>>> [c000000016367880] [c00000000070fc94] iomap_apply+0x1c4/0x780
>>>>> [c000000016367990] [c000000000710330]
>>>>> iomap_file_buffered_write+0xa0/0x120
>>>>> [c0000000163679e0] [c00800000040791c]
>>>>> xfs_file_buffered_aio_write+0x314/0x5e0 [xfs]
>>>>> [c000000016367a90] [c0000000006d74bc] io_write+0x10c/0x460
>>>>> [c000000016367bb0] [c0000000006d80e4] io_issue_sqe+0x8d4/0x1200
>>>>> [c000000016367c70] [c0000000006d8ad0] io_wq_submit_work+0xc0/0x250
>>>>> [c000000016367cb0] [c0000000006e2578]
>>>>> io_worker_handle_work+0x498/0x800
>>>>> [c000000016367d40] [c0000000006e2cdc] io_wqe_worker+0x3fc/0x4f0
>>>>> [c000000016367da0] [c0000000001cb0a4] kthread+0x1c4/0x1d0
>>>>> [c000000016367e10] [c00000000000dbf0]
>>>>> ret_from_kernel_thread+0x5c/0x6c
>>>>>
>>>>> The kernel consider thread AMR value for kernel thread to be
>>>>> AMR_KUAP_BLOCKED. Hence access to userspace is denied. This
>>>>> of course not correct and we should allow userspace access after
>>>>> kthread_use_mm(). To be precise, kthread_use_mm() should inherit the
>>>>> AMR value of the operating address space. But, the AMR value is
>>>>> thread-specific and we inherit the address space and not thread
>>>>> access restrictions. Because of this ignore AMR value when accessing
>>>>> userspace via kernel thread.
>>>>>
>>>>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
>>>>> ---
>>>>> Changes from v1:
>>>>> * Address review feedback from Nick
>>>>>
>>>>> arch/powerpc/include/asm/book3s/64/kup.h | 8 +++++++-
>>>>> 1 file changed, 7 insertions(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/arch/powerpc/include/asm/book3s/64/kup.h
>>>>> b/arch/powerpc/include/asm/book3s/64/kup.h
>>>>> index f50f72e535aa..95f4df99249e 100644
>>>>> --- a/arch/powerpc/include/asm/book3s/64/kup.h
>>>>> +++ b/arch/powerpc/include/asm/book3s/64/kup.h
>>>>> @@ -384,7 +384,13 @@ static __always_inline void
>>>>> allow_user_access(void __user *to, const void __user
>>>>> // This is written so we can resolve to a single case at build
>>>>> time
>>>>> BUILD_BUG_ON(!__builtin_constant_p(dir));
>>>>> - if (mmu_has_feature(MMU_FTR_PKEY))
>>>>> + /*
>>>>> + * if it is a kthread that did kthread_use_mm() don't
>>>>> + * use current_thread_amr().
>>>>
>>>> According to include/linux/sched.h, PF_KTHREAD means /* I am a kernel
>>>> thread */
>>>> It doesn't seem to be related to kthread_use_mm()
>>>
>>> That should be a sufficient check here. if we did reach here without
>>> calling kthread_user_mm, we will crash on access because we don't have
>>> a mm attached to the current process. a kernel thread with
>>> kthread_use_mm has
>>
>> Ok but then the comment doesn't match the check.
>
>
> I was trying to be explict in the comment that we expect the thread to
> have done kthread_use_mm().
>
>>
>> And also the comment in current_thread_amr() is then misleading.
>>
>> Why not do the current->flags & PF_KTHREAD check in current_thread_amr()
>> and return 0 in that case instead of BLOCKED ?
>
> In my view currrent_thread_amr() is more generic and we want to be
> explicit there that a kernel thread AMR is KUAP_BLOCKED. Only when we
> call allow user access, we relax the AMR value.
Just following up on this, as I'd hate to have 5.11 released with this
bug in it for powerpc. It'll obviously also affect other cases of a
kernel thread faulting after having done kthread_use_mm(), though I'm
not sure how widespread that is. In any case, it'll leave io_uring
mostly broken on powerpc if this isn't patched for release.
--
Jens Axboe
^ permalink raw reply
* [PATCH v16 11/12] powerpc: Use OF alloc and free for FDT
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
of_alloc_and_init_fdt() and of_free_fdt() have been defined in
drivers/of/kexec.c to allocate and free memory for FDT.
Use of_alloc_and_init_fdt() and of_free_fdt() to allocate and
initialize the FDT, and to free the FDT respectively.
powerpc sets the FDT address in image_loader_data field in
"struct kimage" and the memory is freed in
kimage_file_post_load_cleanup(). This cleanup function uses kfree()
to free the memory. But since of_alloc_and_init_fdt() uses kvmalloc()
for allocation, the buffer needs to be freed using kvfree().
Define "fdt" field in "struct kimage_arch" for powerpc to store
the address of FDT, and free the memory in powerpc specific
arch_kimage_file_post_load_cleanup().
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Rob Herring <robh@kernel.org>
Suggested-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
---
arch/powerpc/include/asm/kexec.h | 2 ++
arch/powerpc/kexec/elf_64.c | 26 ++++++++++++++++----------
arch/powerpc/kexec/file_load_64.c | 3 +++
3 files changed, 21 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 2c0be93d239a..d7d13cac4d31 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -111,6 +111,8 @@ struct kimage_arch {
unsigned long elf_headers_mem;
unsigned long elf_headers_sz;
void *elf_headers;
+
+ void *fdt;
};
char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
index d0e459bb2f05..51d2d8eb6c1b 100644
--- a/arch/powerpc/kexec/elf_64.c
+++ b/arch/powerpc/kexec/elf_64.c
@@ -19,6 +19,7 @@
#include <linux/kexec.h>
#include <linux/libfdt.h>
#include <linux/module.h>
+#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/slab.h>
#include <linux/types.h>
@@ -32,7 +33,7 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
unsigned int fdt_size;
unsigned long kernel_load_addr;
unsigned long initrd_load_addr = 0, fdt_load_addr;
- void *fdt;
+ void *fdt = NULL;
const void *slave_code;
struct elfhdr ehdr;
char *modified_cmdline = NULL;
@@ -103,18 +104,12 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
}
fdt_size = fdt_totalsize(initial_boot_params) * 2;
- fdt = kmalloc(fdt_size, GFP_KERNEL);
+ fdt = of_alloc_and_init_fdt(fdt_size);
if (!fdt) {
pr_err("Not enough memory for the device tree.\n");
ret = -ENOMEM;
goto out;
}
- ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
- if (ret < 0) {
- pr_err("Error setting up the new device tree.\n");
- ret = -EINVAL;
- goto out;
- }
ret = setup_new_fdt_ppc64(image, fdt, initrd_load_addr,
initrd_len, cmdline);
@@ -131,6 +126,10 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;
+
+ /* FDT will be freed in arch_kimage_file_post_load_cleanup */
+ image->arch.fdt = fdt;
+
fdt_load_addr = kbuf.mem;
pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
@@ -145,8 +144,15 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
kfree(modified_cmdline);
kexec_free_elf_info(&elf_info);
- /* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
- return ret ? ERR_PTR(ret) : fdt;
+ /*
+ * Once FDT buffer has been successfully passed to kexec_add_buffer(),
+ * the FDT buffer address is saved in image->arch.fdt. In that case,
+ * the memory cannot be freed here in case of any other error.
+ */
+ if (ret && !image->arch.fdt)
+ of_free_fdt(fdt);
+
+ return ret ? ERR_PTR(ret) : NULL;
}
const struct kexec_file_ops kexec_elf64_ops = {
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index 3cab318aa3b9..d9d5b5569a6d 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -1113,5 +1113,8 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
image->arch.elf_headers = NULL;
image->arch.elf_headers_sz = 0;
+ of_free_fdt(image->arch.fdt);
+ image->arch.fdt = NULL;
+
return kexec_image_post_load_cleanup_default(image);
}
--
2.30.0
^ permalink raw reply related
* [PATCH v16 12/12] arm64: Enable passing IMA log to next kernel on kexec
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC, if CONFIG_IMA
is enabled, to indicate that the IMA measurement log information is
present in the device tree for ARM64.
Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
arch/arm64/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 05e17351e4f3..8a93573cebb6 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1093,6 +1093,7 @@ config KEXEC
config KEXEC_FILE
bool "kexec file based system call"
select KEXEC_CORE
+ select HAVE_IMA_KEXEC if IMA
help
This is new version of kexec system call. This system call is
file based and takes file descriptors as system call argument
--
2.30.0
^ permalink raw reply related
* [PATCH v16 10/12] arm64: Use OF alloc and free functions for FDT
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
of_alloc_and_init_fdt() and of_free_fdt() have been defined in
drivers/of/kexec.c to allocate and free memory for FDT.
Use of_alloc_and_init_fdt() and of_free_fdt() to allocate and
initialize the FDT, and to free the FDT respectively.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Rob Herring <robh@kernel.org>
---
arch/arm64/kernel/machine_kexec_file.c | 37 +++++++-------------------
1 file changed, 10 insertions(+), 27 deletions(-)
diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 7da22bb7b9d5..7d6cc478f73c 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -29,7 +29,7 @@ const struct kexec_file_ops * const kexec_file_loaders[] = {
int arch_kimage_file_post_load_cleanup(struct kimage *image)
{
- vfree(image->arch.dtb);
+ of_free_fdt(image->arch.dtb);
image->arch.dtb = NULL;
vfree(image->arch.elf_headers);
@@ -57,36 +57,19 @@ static int create_dtb(struct kimage *image,
cmdline_len = cmdline ? strlen(cmdline) : 0;
buf_size = fdt_totalsize(initial_boot_params)
+ cmdline_len + DTB_EXTRA_SPACE;
-
- for (;;) {
- buf = vmalloc(buf_size);
- if (!buf)
- return -ENOMEM;
-
- /* duplicate a device tree blob */
- ret = fdt_open_into(initial_boot_params, buf, buf_size);
- if (ret)
- return -EINVAL;
-
- ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
+ buf = of_alloc_and_init_fdt(buf_size);
+ if (!buf)
+ return -ENOMEM;
+ ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
initrd_len, cmdline);
- if (ret) {
- vfree(buf);
- if (ret == -ENOMEM) {
- /* unlikely, but just in case */
- buf_size += DTB_EXTRA_SPACE;
- continue;
- } else {
- return ret;
- }
- }
-
+ if (!ret) {
/* trim it */
fdt_pack(buf);
*dtb = buf;
+ } else
+ of_free_fdt(buf);
- return 0;
- }
+ return ret;
}
static int prepare_elf_headers(void **addr, unsigned long *sz)
@@ -224,6 +207,6 @@ int load_other_segments(struct kimage *image,
out_err:
image->nr_segments = orig_segments;
- vfree(dtb);
+ of_free_fdt(dtb);
return ret;
}
--
2.30.0
^ permalink raw reply related
* [PATCH v16 08/12] powerpc: Delete unused function delete_fdt_mem_rsv()
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
delete_fdt_mem_rsv() defined in "arch/powerpc/kexec/file_load.c"
has been renamed to fdt_find_and_del_mem_rsv(), and moved to
"drivers/of/kexec.c".
Remove delete_fdt_mem_rsv() in "arch/powerpc/kexec/file_load.c".
Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
arch/powerpc/include/asm/kexec.h | 1 -
arch/powerpc/kexec/file_load.c | 32 --------------------------------
2 files changed, 33 deletions(-)
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 939bc40dfa62..2c0be93d239a 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -118,7 +118,6 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
int setup_purgatory(struct kimage *image, const void *slave_code,
const void *fdt, unsigned long kernel_load_addr,
unsigned long fdt_load_addr);
-int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
#ifdef CONFIG_PPC64
struct kexec_buf;
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index 5dd3a9c45a2d..036c8fb48fc3 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -108,35 +108,3 @@ int setup_purgatory(struct kimage *image, const void *slave_code,
return 0;
}
-
-/**
- * delete_fdt_mem_rsv - delete memory reservation with given address and size
- *
- * Return: 0 on success, or negative errno on error.
- */
-int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)
-{
- int i, ret, num_rsvs = fdt_num_mem_rsv(fdt);
-
- for (i = 0; i < num_rsvs; i++) {
- uint64_t rsv_start, rsv_size;
-
- ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
- if (ret) {
- pr_err("Malformed device tree.\n");
- return -EINVAL;
- }
-
- if (rsv_start == start && rsv_size == size) {
- ret = fdt_del_mem_rsv(fdt, i);
- if (ret) {
- pr_err("Error deleting device tree reservation.\n");
- return -EINVAL;
- }
-
- return 0;
- }
- }
-
- return -ENOENT;
-}
--
2.30.0
^ permalink raw reply related
* [PATCH v16 09/12] of: Define functions to allocate and free FDT
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
Kernel components that use Flattened Device Tree (FDT) allocate kernel
memory and call fdt_open_into() to reorganize the tree into a form
suitable for the read-write operations. These operations can be
combined into a single function to allocate and initialize the FDT
so the different architecures do not have to duplicate the code.
Define of_alloc_and_init_fdt() and of_free_fdt() in drivers/of/kexec.c
to allocate and initialize FDT, and to free the FDT buffer respectively.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Rob Herring <robh@kernel.org>
Suggested-by: Joe Perches <joe@perches.com>
---
drivers/of/kexec.c | 37 +++++++++++++++++++++++++++++++++++++
include/linux/of.h | 2 ++
2 files changed, 39 insertions(+)
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index 5ae0e5d90f55..197e71104f47 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -11,6 +11,7 @@
#include <linux/kernel.h>
#include <linux/kexec.h>
+#include <linux/mm.h>
#include <linux/memblock.h>
#include <linux/libfdt.h>
#include <linux/of.h>
@@ -28,6 +29,42 @@
#define FDT_PROP_RNG_SEED "rng-seed"
#define RNG_SEED_SIZE 128
+/**
+ * of_alloc_and_init_fdt - Allocate and initialize a Flattened device tree
+ *
+ * @fdt_size: Flattened device tree size
+ *
+ * Return the allocated FDT buffer on success, or NULL on error.
+ */
+void *of_alloc_and_init_fdt(unsigned int fdt_size)
+{
+ void *fdt;
+ int ret;
+
+ fdt = kvmalloc(fdt_size, GFP_KERNEL);
+ if (!fdt)
+ return NULL;
+
+ ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
+ if (ret < 0) {
+ pr_err("Error setting up the new device tree.\n");
+ kvfree(fdt);
+ fdt = NULL;
+ }
+
+ return fdt;
+}
+
+/**
+ * of_free_fdt - Free the buffer for Flattened device tree
+ *
+ * @fdt: Flattened device tree buffer to free
+ */
+void of_free_fdt(void *fdt)
+{
+ kvfree(fdt);
+}
+
/**
* fdt_find_and_del_mem_rsv - delete memory reservation with given address and size
*
diff --git a/include/linux/of.h b/include/linux/of.h
index 19f77dd12507..9f0261761e28 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -563,6 +563,8 @@ struct kimage;
int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr, unsigned long initrd_len,
const char *cmdline);
+void *of_alloc_and_init_fdt(unsigned int fdt_size);
+void of_free_fdt(void *fdt);
#ifdef CONFIG_IMA_KEXEC
int of_ima_add_kexec_buffer(struct kimage *image,
--
2.30.0
^ permalink raw reply related
* [PATCH v16 07/12] kexec: Use fdt_appendprop_addrrange() to add ima buffer to FDT
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
fdt_appendprop_addrrange() function adds a property, with the given name,
to the device tree at the given node offset, and also sets the address
and size of the property. This function should be used to add
"linux,ima-kexec-buffer" property to the device tree and set the address
and size of the IMA measurement buffer, instead of using custom function.
Use fdt_appendprop_addrrange() to add "linux,ima-kexec-buffer" property
to the device tree. This property holds the address and size of
the IMA measurement buffer that needs to be passed from the current
kernel to the next kernel across kexec system call.
Remove custom code that is used in setup_ima_buffer() to add
"linux,ima-kexec-buffer" property to the device tree.
Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
---
drivers/of/kexec.c | 57 ++++------------------------------------------
1 file changed, 5 insertions(+), 52 deletions(-)
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index 7ee4f498ca19..5ae0e5d90f55 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -232,36 +232,6 @@ int of_ima_add_kexec_buffer(struct kimage *image,
return 0;
}
-/**
- * write_number - Convert number to big-endian format
- *
- * @p: Buffer to write the number to
- * @value: Number to convert
- * @cells: Number of cells
- *
- * Return: 0 on success, or negative errno on error.
- */
-static int write_number(void *p, u64 value, int cells)
-{
- if (cells == 1) {
- u32 tmp;
-
- if (value > U32_MAX)
- return -EINVAL;
-
- tmp = cpu_to_be32(value);
- memcpy(p, &tmp, sizeof(tmp));
- } else if (cells == 2) {
- u64 tmp;
-
- tmp = cpu_to_be64(value);
- memcpy(p, &tmp, sizeof(tmp));
- } else
- return -EINVAL;
-
- return 0;
-}
-
/**
* setup_ima_buffer - add IMA buffer information to the fdt
* @image: kexec image being loaded.
@@ -273,32 +243,15 @@ static int write_number(void *p, u64 value, int cells)
static int setup_ima_buffer(const struct kimage *image, void *fdt,
int chosen_node)
{
- int ret, addr_cells, size_cells, entry_size;
- u8 value[16];
+ int ret;
if (!image->ima_buffer_size)
return 0;
- ret = get_addr_size_cells(&addr_cells, &size_cells);
- if (ret)
- return ret;
-
- entry_size = 4 * (addr_cells + size_cells);
-
- if (entry_size > sizeof(value))
- return -EINVAL;
-
- ret = write_number(value, image->ima_buffer_addr, addr_cells);
- if (ret)
- return ret;
-
- ret = write_number(value + 4 * addr_cells, image->ima_buffer_size,
- size_cells);
- if (ret)
- return ret;
-
- ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
- entry_size);
+ ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+ "linux,ima-kexec-buffer",
+ image->ima_buffer_addr,
+ image->ima_buffer_size);
if (ret < 0)
return -EINVAL;
--
2.30.0
^ permalink raw reply related
* [PATCH v16 06/12] powerpc: Move arch independent ima kexec functions to drivers/of/kexec.c
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
The functions defined in "arch/powerpc/kexec/ima.c" handle setting up
and freeing the resources required to carry over the IMA measurement
list from the current kernel to the next kernel across kexec system call.
These functions do not have architecture specific code, but are
currently limited to powerpc.
Move setup_ima_buffer() call into of_kexec_setup_new_fdt() defined in
"drivers/of/kexec.c". Call of_kexec_setup_new_fdt() from
setup_new_fdt_ppc64() and remove setup_new_fdt() in
"arch/powerpc/kexec/file_load.c".
Move the remaining architecture independent functions from
"arch/powerpc/kexec/ima.c" to "drivers/of/kexec.c".
Delete "arch/powerpc/kexec/ima.c" and "arch/powerpc/include/asm/ima.h".
Remove references to the deleted files in powerpc and in ima.
Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
arch/powerpc/Kconfig | 2 +-
arch/powerpc/include/asm/ima.h | 27 ----
arch/powerpc/include/asm/kexec.h | 3 -
arch/powerpc/kexec/Makefile | 7 -
arch/powerpc/kexec/file_load.c | 35 -----
arch/powerpc/kexec/file_load_64.c | 4 +-
arch/powerpc/kexec/ima.c | 202 -------------------------
drivers/of/kexec.c | 239 ++++++++++++++++++++++++++++++
include/linux/of.h | 2 +
security/integrity/ima/ima.h | 4 -
10 files changed, 245 insertions(+), 280 deletions(-)
delete mode 100644 arch/powerpc/include/asm/ima.h
delete mode 100644 arch/powerpc/kexec/ima.c
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 107bb4319e0e..d6e593ad270e 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -554,7 +554,7 @@ config KEXEC
config KEXEC_FILE
bool "kexec file based system call"
select KEXEC_CORE
- select HAVE_IMA_KEXEC
+ select HAVE_IMA_KEXEC if IMA
select BUILD_BIN2C
select KEXEC_ELF
depends on PPC64
diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h
deleted file mode 100644
index 51f64fd06c19..000000000000
--- a/arch/powerpc/include/asm/ima.h
+++ /dev/null
@@ -1,27 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_POWERPC_IMA_H
-#define _ASM_POWERPC_IMA_H
-
-struct kimage;
-
-int ima_get_kexec_buffer(void **addr, size_t *size);
-int ima_free_kexec_buffer(void);
-
-#ifdef CONFIG_IMA
-void remove_ima_buffer(void *fdt, int chosen_node);
-#else
-static inline void remove_ima_buffer(void *fdt, int chosen_node) {}
-#endif
-
-#ifdef CONFIG_IMA_KEXEC
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);
-#else
-static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
- int chosen_node)
-{
- remove_ima_buffer(fdt, chosen_node);
- return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */
-
-#endif /* _ASM_POWERPC_IMA_H */
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 2248dc27080b..939bc40dfa62 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -118,9 +118,6 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
int setup_purgatory(struct kimage *image, const void *slave_code,
const void *fdt, unsigned long kernel_load_addr,
unsigned long fdt_load_addr);
-int setup_new_fdt(const struct kimage *image, void *fdt,
- unsigned long initrd_load_addr, unsigned long initrd_len,
- const char *cmdline);
int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
#ifdef CONFIG_PPC64
diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
index 4aff6846c772..b6c52608cb49 100644
--- a/arch/powerpc/kexec/Makefile
+++ b/arch/powerpc/kexec/Makefile
@@ -9,13 +9,6 @@ obj-$(CONFIG_PPC32) += relocate_32.o
obj-$(CONFIG_KEXEC_FILE) += file_load.o ranges.o file_load_$(BITS).o elf_$(BITS).o
-ifdef CONFIG_HAVE_IMA_KEXEC
-ifdef CONFIG_IMA
-obj-y += ima.o
-endif
-endif
-
-
# Disable GCOV, KCOV & sanitizers in odd or sensitive code
GCOV_PROFILE_core_$(BITS).o := n
KCOV_INSTRUMENT_core_$(BITS).o := n
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index 956bcb2d1ec2..5dd3a9c45a2d 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -20,7 +20,6 @@
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
#include <asm/setup.h>
-#include <asm/ima.h>
#define SLAVE_CODE_SIZE 256 /* First 0x100 bytes */
@@ -141,37 +140,3 @@ int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)
return -ENOENT;
}
-
-/*
- * setup_new_fdt - modify /chosen and memory reservation for the next kernel
- * @image: kexec image being loaded.
- * @fdt: Flattened device tree for the next kernel.
- * @initrd_load_addr: Address where the next initrd will be loaded.
- * @initrd_len: Size of the next initrd, or 0 if there will be none.
- * @cmdline: Command line for the next kernel, or NULL if there will
- * be none.
- *
- * Return: 0 on success, or negative errno on error.
- */
-int setup_new_fdt(const struct kimage *image, void *fdt,
- unsigned long initrd_load_addr, unsigned long initrd_len,
- const char *cmdline)
-{
- int ret;
-
- ret = of_kexec_setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
- if (ret)
- goto err;
-
- ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
- if (ret) {
- pr_err("Error setting up the new device tree.\n");
- return ret;
- }
-
- return 0;
-
-err:
- pr_err("Error setting up the new device tree.\n");
- return -EINVAL;
-}
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index a05c19b3cc60..3cab318aa3b9 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -17,6 +17,7 @@
#include <linux/kexec.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
+#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/memblock.h>
#include <linux/slab.h>
@@ -944,7 +945,8 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
struct crash_mem *umem = NULL, *rmem = NULL;
int i, nr_ranges, ret;
- ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
+ ret = of_kexec_setup_new_fdt(image, fdt, initrd_load_addr, initrd_len,
+ cmdline);
if (ret)
goto out;
diff --git a/arch/powerpc/kexec/ima.c b/arch/powerpc/kexec/ima.c
deleted file mode 100644
index ed38125e2f87..000000000000
--- a/arch/powerpc/kexec/ima.c
+++ /dev/null
@@ -1,202 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2016 IBM Corporation
- *
- * Authors:
- * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
- */
-
-#include <linux/slab.h>
-#include <linux/kexec.h>
-#include <linux/of.h>
-#include <linux/memblock.h>
-#include <linux/libfdt.h>
-
-static int get_addr_size_cells(int *addr_cells, int *size_cells)
-{
- struct device_node *root;
-
- root = of_find_node_by_path("/");
- if (!root)
- return -EINVAL;
-
- *addr_cells = of_n_addr_cells(root);
- *size_cells = of_n_size_cells(root);
-
- of_node_put(root);
-
- return 0;
-}
-
-static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
- size_t *size)
-{
- int ret, addr_cells, size_cells;
-
- ret = get_addr_size_cells(&addr_cells, &size_cells);
- if (ret)
- return ret;
-
- if (len < 4 * (addr_cells + size_cells))
- return -ENOENT;
-
- *addr = of_read_number(prop, addr_cells);
- *size = of_read_number(prop + 4 * addr_cells, size_cells);
-
- return 0;
-}
-
-/**
- * ima_get_kexec_buffer - get IMA buffer from the previous kernel
- * @addr: On successful return, set to point to the buffer contents.
- * @size: On successful return, set to the buffer size.
- *
- * Return: 0 on success, negative errno on error.
- */
-int ima_get_kexec_buffer(void **addr, size_t *size)
-{
- int ret, len;
- unsigned long tmp_addr;
- size_t tmp_size;
- const void *prop;
-
- prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len);
- if (!prop)
- return -ENOENT;
-
- ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
- if (ret)
- return ret;
-
- *addr = __va(tmp_addr);
- *size = tmp_size;
-
- return 0;
-}
-
-/**
- * ima_free_kexec_buffer - free memory used by the IMA buffer
- */
-int ima_free_kexec_buffer(void)
-{
- int ret;
- unsigned long addr;
- size_t size;
- struct property *prop;
-
- prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL);
- if (!prop)
- return -ENOENT;
-
- ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
- if (ret)
- return ret;
-
- ret = of_remove_property(of_chosen, prop);
- if (ret)
- return ret;
-
- return memblock_free(addr, size);
-
-}
-
-/**
- * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
- *
- * The IMA measurement buffer is of no use to a subsequent kernel, so we always
- * remove it from the device tree.
- */
-void remove_ima_buffer(void *fdt, int chosen_node)
-{
- int ret, len;
- unsigned long addr;
- size_t size;
- const void *prop;
-
- prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
- if (!prop)
- return;
-
- ret = do_get_kexec_buffer(prop, len, &addr, &size);
- fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
- if (ret)
- return;
-
- ret = delete_fdt_mem_rsv(fdt, addr, size);
- if (!ret)
- pr_debug("Removed old IMA buffer reservation.\n");
-}
-
-#ifdef CONFIG_IMA_KEXEC
-static int write_number(void *p, u64 value, int cells)
-{
- if (cells == 1) {
- u32 tmp;
-
- if (value > U32_MAX)
- return -EINVAL;
-
- tmp = cpu_to_be32(value);
- memcpy(p, &tmp, sizeof(tmp));
- } else if (cells == 2) {
- u64 tmp;
-
- tmp = cpu_to_be64(value);
- memcpy(p, &tmp, sizeof(tmp));
- } else
- return -EINVAL;
-
- return 0;
-}
-
-/**
- * setup_ima_buffer - add IMA buffer information to the fdt
- * @image: kexec image being loaded.
- * @fdt: Flattened device tree for the next kernel.
- * @chosen_node: Offset to the chosen node.
- *
- * Return: 0 on success, or negative errno on error.
- */
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
-{
- int ret, addr_cells, size_cells, entry_size;
- u8 value[16];
-
- remove_ima_buffer(fdt, chosen_node);
- if (!image->ima_buffer_size)
- return 0;
-
- ret = get_addr_size_cells(&addr_cells, &size_cells);
- if (ret)
- return ret;
-
- entry_size = 4 * (addr_cells + size_cells);
-
- if (entry_size > sizeof(value))
- return -EINVAL;
-
- ret = write_number(value, image->ima_buffer_addr, addr_cells);
- if (ret)
- return ret;
-
- ret = write_number(value + 4 * addr_cells, image->ima_buffer_size,
- size_cells);
- if (ret)
- return ret;
-
- ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
- entry_size);
- if (ret < 0)
- return -EINVAL;
-
- ret = fdt_add_mem_rsv(fdt, image->ima_buffer_addr,
- image->ima_buffer_size);
- if (ret)
- return -EINVAL;
-
- pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
- image->ima_buffer_addr, image->ima_buffer_size);
-
- return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index efbf54f164fd..7ee4f498ca19 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -11,6 +11,7 @@
#include <linux/kernel.h>
#include <linux/kexec.h>
+#include <linux/memblock.h>
#include <linux/libfdt.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
@@ -63,6 +64,152 @@ static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon
return -ENOENT;
}
+
+/**
+ * get_addr_size_cells - Get address and size of root node
+ *
+ * @addr_cells: Return address of the root node
+ * @size_cells: Return size of the root node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int get_addr_size_cells(int *addr_cells, int *size_cells)
+{
+ struct device_node *root;
+
+ root = of_find_node_by_path("/");
+ if (!root)
+ return -EINVAL;
+
+ *addr_cells = of_n_addr_cells(root);
+ *size_cells = of_n_size_cells(root);
+
+ of_node_put(root);
+
+ return 0;
+}
+
+/**
+ * do_get_kexec_buffer - Get address and size of device tree property
+ *
+ * @prop: Device tree property
+ * @len: Size of @prop
+ * @addr: Return address of the node
+ * @size: Return size of the node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
+ size_t *size)
+{
+ int ret, addr_cells, size_cells;
+
+ ret = get_addr_size_cells(&addr_cells, &size_cells);
+ if (ret)
+ return ret;
+
+ if (len < 4 * (addr_cells + size_cells))
+ return -ENOENT;
+
+ *addr = of_read_number(prop, addr_cells);
+ *size = of_read_number(prop + 4 * addr_cells, size_cells);
+
+ return 0;
+}
+
+/**
+ * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
+ *
+ * @fdt: Flattened Device Tree to update
+ * @chosen_node: Offset to the chosen node in the device tree
+ *
+ * The IMA measurement buffer is of no use to a subsequent kernel, so we always
+ * remove it from the device tree.
+ */
+static void remove_ima_buffer(void *fdt, int chosen_node)
+{
+ int ret, len;
+ unsigned long addr;
+ size_t size;
+ const void *prop;
+
+ if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
+ return;
+
+ prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
+ if (!prop)
+ return;
+
+ ret = do_get_kexec_buffer(prop, len, &addr, &size);
+ fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
+ if (ret)
+ return;
+
+ ret = fdt_find_and_del_mem_rsv(fdt, addr, size);
+ if (!ret)
+ pr_debug("Removed old IMA buffer reservation.\n");
+}
+
+/**
+ * ima_get_kexec_buffer - get IMA buffer from the previous kernel
+ * @addr: On successful return, set to point to the buffer contents.
+ * @size: On successful return, set to the buffer size.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int ima_get_kexec_buffer(void **addr, size_t *size)
+{
+ int ret, len;
+ unsigned long tmp_addr;
+ size_t tmp_size;
+ const void *prop;
+
+ if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
+ return -ENOTSUPP;
+
+ prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len);
+ if (!prop)
+ return -ENOENT;
+
+ ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
+ if (ret)
+ return ret;
+
+ *addr = __va(tmp_addr);
+ *size = tmp_size;
+
+ return 0;
+}
+
+/**
+ * ima_free_kexec_buffer - free memory used by the IMA buffer
+ */
+int ima_free_kexec_buffer(void)
+{
+ int ret;
+ unsigned long addr;
+ size_t size;
+ struct property *prop;
+
+ if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
+ return -ENOTSUPP;
+
+ prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL);
+ if (!prop)
+ return -ENOENT;
+
+ ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
+ if (ret)
+ return ret;
+
+ ret = of_remove_property(of_chosen, prop);
+ if (ret)
+ return ret;
+
+ return memblock_free(addr, size);
+
+}
+
#ifdef CONFIG_IMA_KEXEC
/**
* of_ima_add_kexec_buffer - Add IMA buffer for next kernel
@@ -84,6 +231,93 @@ int of_ima_add_kexec_buffer(struct kimage *image,
return 0;
}
+
+/**
+ * write_number - Convert number to big-endian format
+ *
+ * @p: Buffer to write the number to
+ * @value: Number to convert
+ * @cells: Number of cells
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int write_number(void *p, u64 value, int cells)
+{
+ if (cells == 1) {
+ u32 tmp;
+
+ if (value > U32_MAX)
+ return -EINVAL;
+
+ tmp = cpu_to_be32(value);
+ memcpy(p, &tmp, sizeof(tmp));
+ } else if (cells == 2) {
+ u64 tmp;
+
+ tmp = cpu_to_be64(value);
+ memcpy(p, &tmp, sizeof(tmp));
+ } else
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * setup_ima_buffer - add IMA buffer information to the fdt
+ * @image: kexec image being loaded.
+ * @fdt: Flattened device tree for the next kernel.
+ * @chosen_node: Offset to the chosen node.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int setup_ima_buffer(const struct kimage *image, void *fdt,
+ int chosen_node)
+{
+ int ret, addr_cells, size_cells, entry_size;
+ u8 value[16];
+
+ if (!image->ima_buffer_size)
+ return 0;
+
+ ret = get_addr_size_cells(&addr_cells, &size_cells);
+ if (ret)
+ return ret;
+
+ entry_size = 4 * (addr_cells + size_cells);
+
+ if (entry_size > sizeof(value))
+ return -EINVAL;
+
+ ret = write_number(value, image->ima_buffer_addr, addr_cells);
+ if (ret)
+ return ret;
+
+ ret = write_number(value + 4 * addr_cells, image->ima_buffer_size,
+ size_cells);
+ if (ret)
+ return ret;
+
+ ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
+ entry_size);
+ if (ret < 0)
+ return -EINVAL;
+
+ ret = fdt_add_mem_rsv(fdt, image->ima_buffer_addr,
+ image->ima_buffer_size);
+ if (ret)
+ return -EINVAL;
+
+ pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
+ image->ima_buffer_addr, image->ima_buffer_size);
+
+ return 0;
+}
+#else /* CONFIG_IMA_KEXEC */
+static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
+ int chosen_node)
+{
+ return 0;
+}
#endif /* CONFIG_IMA_KEXEC */
/*
@@ -250,6 +484,11 @@ int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
}
ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+ if (ret)
+ goto out;
+
+ remove_ima_buffer(fdt, chosen_node);
+ ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
out:
if (ret)
diff --git a/include/linux/of.h b/include/linux/of.h
index 551117c32773..19f77dd12507 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -569,6 +569,8 @@ int of_ima_add_kexec_buffer(struct kimage *image,
unsigned long load_addr, size_t size);
#endif /* CONFIG_IMA_KEXEC */
+int ima_get_kexec_buffer(void **addr, size_t *size);
+int ima_free_kexec_buffer(void);
#else /* CONFIG_OF */
static inline void of_core_init(void)
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index aa312472c7c5..fdae37fa7051 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -24,10 +24,6 @@
#include "../integrity.h"
-#ifdef CONFIG_HAVE_IMA_KEXEC
-#include <asm/ima.h>
-#endif
-
enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 };
--
2.30.0
^ permalink raw reply related
* [PATCH v16 05/12] powerpc: Move ima buffer fields to struct kimage
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
The fields ima_buffer_addr and ima_buffer_size in "struct kimage_arch"
for powerpc are used to carry forward the IMA measurement list across
kexec system call. These fields are not architecture specific, but are
currently limited to powerpc.
arch_ima_add_kexec_buffer() defined in "arch/powerpc/kexec/ima.c"
sets ima_buffer_addr and ima_buffer_size for the kexec system call.
This function does not have architecture specific code, but is
currently limited to powerpc.
Move ima_buffer_addr and ima_buffer_size to "struct kimage".
Rename arch_ima_add_kexec_buffer() to of_ima_add_kexec_buffer()
and move it in drivers/of/kexec.c.
Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: Will Deacon <will@kernel.org>
---
arch/powerpc/include/asm/ima.h | 3 ---
arch/powerpc/include/asm/kexec.h | 5 -----
arch/powerpc/kexec/ima.c | 29 ++++++-----------------------
drivers/of/kexec.c | 23 +++++++++++++++++++++++
include/linux/kexec.h | 5 +++++
include/linux/of.h | 5 +++++
security/integrity/ima/ima_kexec.c | 3 ++-
7 files changed, 41 insertions(+), 32 deletions(-)
diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h
index ead488cf3981..51f64fd06c19 100644
--- a/arch/powerpc/include/asm/ima.h
+++ b/arch/powerpc/include/asm/ima.h
@@ -14,9 +14,6 @@ static inline void remove_ima_buffer(void *fdt, int chosen_node) {}
#endif
#ifdef CONFIG_IMA_KEXEC
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
- size_t size);
-
int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);
#else
static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index dbf09d2f36d0..2248dc27080b 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -111,11 +111,6 @@ struct kimage_arch {
unsigned long elf_headers_mem;
unsigned long elf_headers_sz;
void *elf_headers;
-
-#ifdef CONFIG_IMA_KEXEC
- phys_addr_t ima_buffer_addr;
- size_t ima_buffer_size;
-#endif
};
char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
diff --git a/arch/powerpc/kexec/ima.c b/arch/powerpc/kexec/ima.c
index 720e50e490b6..ed38125e2f87 100644
--- a/arch/powerpc/kexec/ima.c
+++ b/arch/powerpc/kexec/ima.c
@@ -128,23 +128,6 @@ void remove_ima_buffer(void *fdt, int chosen_node)
}
#ifdef CONFIG_IMA_KEXEC
-/**
- * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
- *
- * Architectures should use this function to pass on the IMA buffer
- * information to the next kernel.
- *
- * Return: 0 on success, negative errno on error.
- */
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
- size_t size)
-{
- image->arch.ima_buffer_addr = load_addr;
- image->arch.ima_buffer_size = size;
-
- return 0;
-}
-
static int write_number(void *p, u64 value, int cells)
{
if (cells == 1) {
@@ -180,7 +163,7 @@ int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
u8 value[16];
remove_ima_buffer(fdt, chosen_node);
- if (!image->arch.ima_buffer_size)
+ if (!image->ima_buffer_size)
return 0;
ret = get_addr_size_cells(&addr_cells, &size_cells);
@@ -192,11 +175,11 @@ int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
if (entry_size > sizeof(value))
return -EINVAL;
- ret = write_number(value, image->arch.ima_buffer_addr, addr_cells);
+ ret = write_number(value, image->ima_buffer_addr, addr_cells);
if (ret)
return ret;
- ret = write_number(value + 4 * addr_cells, image->arch.ima_buffer_size,
+ ret = write_number(value + 4 * addr_cells, image->ima_buffer_size,
size_cells);
if (ret)
return ret;
@@ -206,13 +189,13 @@ int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
if (ret < 0)
return -EINVAL;
- ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
- image->arch.ima_buffer_size);
+ ret = fdt_add_mem_rsv(fdt, image->ima_buffer_addr,
+ image->ima_buffer_size);
if (ret)
return -EINVAL;
pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
- image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
+ image->ima_buffer_addr, image->ima_buffer_size);
return 0;
}
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index 4afd3cc1c04a..efbf54f164fd 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -63,6 +63,29 @@ static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon
return -ENOENT;
}
+#ifdef CONFIG_IMA_KEXEC
+/**
+ * of_ima_add_kexec_buffer - Add IMA buffer for next kernel
+ *
+ * @image: kimage struct to set IMA buffer data
+ * @load_addr: Starting address where IMA buffer is loaded at
+ * @size: Number of bytes in the IMA buffer
+ *
+ * Use this function to pass on the IMA buffer information to
+ * the next kernel across kexec system call.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int of_ima_add_kexec_buffer(struct kimage *image,
+ unsigned long load_addr, size_t size)
+{
+ image->ima_buffer_addr = load_addr;
+ image->ima_buffer_size = size;
+
+ return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */
+
/*
* of_kexec_setup_new_fdt - modify /chosen and memory reservation for the next kernel
*
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 9e93bef52968..c142a1e5568d 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -300,6 +300,11 @@ struct kimage {
/* Information for loading purgatory */
struct purgatory_info purgatory_info;
#endif
+
+#ifdef CONFIG_IMA_KEXEC
+ phys_addr_t ima_buffer_addr;
+ size_t ima_buffer_size;
+#endif
};
/* kexec interface functions */
diff --git a/include/linux/of.h b/include/linux/of.h
index 41e256adf758..551117c32773 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -564,6 +564,11 @@ int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr, unsigned long initrd_len,
const char *cmdline);
+#ifdef CONFIG_IMA_KEXEC
+int of_ima_add_kexec_buffer(struct kimage *image,
+ unsigned long load_addr, size_t size);
+#endif /* CONFIG_IMA_KEXEC */
+
#else /* CONFIG_OF */
static inline void of_core_init(void)
diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c
index 121de3e04af2..345b78515774 100644
--- a/security/integrity/ima/ima_kexec.c
+++ b/security/integrity/ima/ima_kexec.c
@@ -10,6 +10,7 @@
#include <linux/seq_file.h>
#include <linux/vmalloc.h>
#include <linux/kexec.h>
+#include <linux/of.h>
#include "ima.h"
#ifdef CONFIG_IMA_KEXEC
@@ -122,7 +123,7 @@ void ima_add_kexec_buffer(struct kimage *image)
return;
}
- ret = arch_ima_add_kexec_buffer(image, kbuf.mem, kexec_segment_size);
+ ret = of_ima_add_kexec_buffer(image, kbuf.mem, kexec_segment_size);
if (ret) {
pr_err("Error passing over kexec measurement buffer.\n");
return;
--
2.30.0
^ permalink raw reply related
* [PATCH v16 04/12] powerpc: Use common of_kexec_setup_new_fdt()
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
From: Rob Herring <robh@kernel.org>
The code for setting up the /chosen node in the device tree
and updating the memory reservation for the next kernel has been
moved to of_kexec_setup_new_fdt() defined in "drivers/of/kexec.c".
Use the common of_kexec_setup_new_fdt() to setup the device tree
and update the memory reservation for kexec for powerpc.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
arch/powerpc/kexec/file_load.c | 125 ++-------------------------------
1 file changed, 6 insertions(+), 119 deletions(-)
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index e452b11df631..956bcb2d1ec2 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -16,6 +16,7 @@
#include <linux/slab.h>
#include <linux/kexec.h>
+#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
#include <asm/setup.h>
@@ -156,132 +157,18 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
unsigned long initrd_load_addr, unsigned long initrd_len,
const char *cmdline)
{
- int ret, chosen_node;
- const void *prop;
-
- /* Remove memory reservation for the current device tree. */
- ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
- fdt_totalsize(initial_boot_params));
- if (ret == 0)
- pr_debug("Removed old device tree reservation.\n");
- else if (ret != -ENOENT)
- return ret;
-
- chosen_node = fdt_path_offset(fdt, "/chosen");
- if (chosen_node == -FDT_ERR_NOTFOUND) {
- chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
- "chosen");
- if (chosen_node < 0) {
- pr_err("Error creating /chosen.\n");
- return -EINVAL;
- }
- } else if (chosen_node < 0) {
- pr_err("Malformed device tree: error reading /chosen.\n");
- return -EINVAL;
- }
-
- /* Did we boot using an initrd? */
- prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
- if (prop) {
- uint64_t tmp_start, tmp_end, tmp_size;
-
- tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
-
- prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
- if (!prop) {
- pr_err("Malformed device tree.\n");
- return -EINVAL;
- }
- tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
-
- /*
- * kexec reserves exact initrd size, while firmware may
- * reserve a multiple of PAGE_SIZE, so check for both.
- */
- tmp_size = tmp_end - tmp_start;
- ret = delete_fdt_mem_rsv(fdt, tmp_start, tmp_size);
- if (ret == -ENOENT)
- ret = delete_fdt_mem_rsv(fdt, tmp_start,
- round_up(tmp_size, PAGE_SIZE));
- if (ret == 0)
- pr_debug("Removed old initrd reservation.\n");
- else if (ret != -ENOENT)
- return ret;
-
- /* If there's no new initrd, delete the old initrd's info. */
- if (initrd_len == 0) {
- ret = fdt_delprop(fdt, chosen_node,
- "linux,initrd-start");
- if (ret) {
- pr_err("Error deleting linux,initrd-start.\n");
- return -EINVAL;
- }
-
- ret = fdt_delprop(fdt, chosen_node, "linux,initrd-end");
- if (ret) {
- pr_err("Error deleting linux,initrd-end.\n");
- return -EINVAL;
- }
- }
- }
-
- if (initrd_len) {
- ret = fdt_setprop_u64(fdt, chosen_node,
- "linux,initrd-start",
- initrd_load_addr);
- if (ret < 0)
- goto err;
-
- /* initrd-end is the first address after the initrd image. */
- ret = fdt_setprop_u64(fdt, chosen_node, "linux,initrd-end",
- initrd_load_addr + initrd_len);
- if (ret < 0)
- goto err;
-
- ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
- if (ret) {
- pr_err("Error reserving initrd memory: %s\n",
- fdt_strerror(ret));
- return -EINVAL;
- }
- }
-
- if (cmdline != NULL) {
- ret = fdt_setprop_string(fdt, chosen_node, "bootargs", cmdline);
- if (ret < 0)
- goto err;
- } else {
- ret = fdt_delprop(fdt, chosen_node, "bootargs");
- if (ret && ret != -FDT_ERR_NOTFOUND) {
- pr_err("Error deleting bootargs.\n");
- return -EINVAL;
- }
- }
+ int ret;
- if (image->type == KEXEC_TYPE_CRASH) {
- /*
- * Avoid elfcorehdr from being stomped on in kdump kernel by
- * setting up memory reserve map.
- */
- ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
- image->arch.elf_headers_sz);
- if (ret) {
- pr_err("Error reserving elfcorehdr memory: %s\n",
- fdt_strerror(ret));
- goto err;
- }
- }
+ ret = of_kexec_setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
+ if (ret)
+ goto err;
- ret = setup_ima_buffer(image, fdt, chosen_node);
+ ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
if (ret) {
pr_err("Error setting up the new device tree.\n");
return ret;
}
- ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
- if (ret)
- goto err;
-
return 0;
err:
--
2.30.0
^ permalink raw reply related
* [PATCH v16 03/12] arm64: Use common of_kexec_setup_new_fdt()
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
From: Rob Herring <robh@kernel.org>
The code for setting up the /chosen node in the device tree
and updating the memory reservation for the next kernel has been
moved to of_kexec_setup_new_fdt() defined in "drivers/of/kexec.c".
Use the common of_kexec_setup_new_fdt() to setup the device tree
and update the memory reservation for kexec for arm64.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Acked-by: Will Deacon <will@kernel.org>
---
arch/arm64/kernel/machine_kexec_file.c | 123 +------------------------
1 file changed, 3 insertions(+), 120 deletions(-)
diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 03210f644790..7da22bb7b9d5 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -15,23 +15,12 @@
#include <linux/kexec.h>
#include <linux/libfdt.h>
#include <linux/memblock.h>
+#include <linux/of.h>
#include <linux/of_fdt.h>
-#include <linux/random.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/vmalloc.h>
-#include <asm/byteorder.h>
-
-/* relevant device tree properties */
-#define FDT_PROP_KEXEC_ELFHDR "linux,elfcorehdr"
-#define FDT_PROP_MEM_RANGE "linux,usable-memory-range"
-#define FDT_PROP_INITRD_START "linux,initrd-start"
-#define FDT_PROP_INITRD_END "linux,initrd-end"
-#define FDT_PROP_BOOTARGS "bootargs"
-#define FDT_PROP_KASLR_SEED "kaslr-seed"
-#define FDT_PROP_RNG_SEED "rng-seed"
-#define RNG_SEED_SIZE 128
const struct kexec_file_ops * const kexec_file_loaders[] = {
&kexec_image_ops,
@@ -50,112 +39,6 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
return kexec_image_post_load_cleanup_default(image);
}
-static int setup_dtb(struct kimage *image,
- unsigned long initrd_load_addr, unsigned long initrd_len,
- char *cmdline, void *dtb)
-{
- int off, ret;
-
- ret = fdt_path_offset(dtb, "/chosen");
- if (ret < 0)
- goto out;
-
- off = ret;
-
- ret = fdt_delprop(dtb, off, FDT_PROP_KEXEC_ELFHDR);
- if (ret && ret != -FDT_ERR_NOTFOUND)
- goto out;
- ret = fdt_delprop(dtb, off, FDT_PROP_MEM_RANGE);
- if (ret && ret != -FDT_ERR_NOTFOUND)
- goto out;
-
- if (image->type == KEXEC_TYPE_CRASH) {
- /* add linux,elfcorehdr */
- ret = fdt_appendprop_addrrange(dtb, 0, off,
- FDT_PROP_KEXEC_ELFHDR,
- image->arch.elf_headers_mem,
- image->arch.elf_headers_sz);
- if (ret)
- return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
-
- /* add linux,usable-memory-range */
- ret = fdt_appendprop_addrrange(dtb, 0, off,
- FDT_PROP_MEM_RANGE,
- crashk_res.start,
- crashk_res.end - crashk_res.start + 1);
- if (ret)
- return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
- }
-
- /* add bootargs */
- if (cmdline) {
- ret = fdt_setprop_string(dtb, off, FDT_PROP_BOOTARGS, cmdline);
- if (ret)
- goto out;
- } else {
- ret = fdt_delprop(dtb, off, FDT_PROP_BOOTARGS);
- if (ret && (ret != -FDT_ERR_NOTFOUND))
- goto out;
- }
-
- /* add initrd-* */
- if (initrd_load_addr) {
- ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_START,
- initrd_load_addr);
- if (ret)
- goto out;
-
- ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_END,
- initrd_load_addr + initrd_len);
- if (ret)
- goto out;
- } else {
- ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_START);
- if (ret && (ret != -FDT_ERR_NOTFOUND))
- goto out;
-
- ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_END);
- if (ret && (ret != -FDT_ERR_NOTFOUND))
- goto out;
- }
-
- /* add kaslr-seed */
- ret = fdt_delprop(dtb, off, FDT_PROP_KASLR_SEED);
- if (ret == -FDT_ERR_NOTFOUND)
- ret = 0;
- else if (ret)
- goto out;
-
- if (rng_is_initialized()) {
- u64 seed = get_random_u64();
- ret = fdt_setprop_u64(dtb, off, FDT_PROP_KASLR_SEED, seed);
- if (ret)
- goto out;
- } else {
- pr_notice("RNG is not initialised: omitting \"%s\" property\n",
- FDT_PROP_KASLR_SEED);
- }
-
- /* add rng-seed */
- if (rng_is_initialized()) {
- void *rng_seed;
- ret = fdt_setprop_placeholder(dtb, off, FDT_PROP_RNG_SEED,
- RNG_SEED_SIZE, &rng_seed);
- if (ret)
- goto out;
- get_random_bytes(rng_seed, RNG_SEED_SIZE);
- } else {
- pr_notice("RNG is not initialised: omitting \"%s\" property\n",
- FDT_PROP_RNG_SEED);
- }
-
-out:
- if (ret)
- return (ret == -FDT_ERR_NOSPACE) ? -ENOMEM : -EINVAL;
-
- return 0;
-}
-
/*
* More space needed so that we can add initrd, bootargs, kaslr-seed,
* rng-seed, userable-memory-range and elfcorehdr.
@@ -185,8 +68,8 @@ static int create_dtb(struct kimage *image,
if (ret)
return -EINVAL;
- ret = setup_dtb(image, initrd_load_addr, initrd_len,
- cmdline, buf);
+ ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
+ initrd_len, cmdline);
if (ret) {
vfree(buf);
if (ret == -ENOMEM) {
--
2.30.0
^ permalink raw reply related
* [PATCH v16 00/12] Carry forward IMA measurement log on kexec on ARM64
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
On kexec file load Integrity Measurement Architecture (IMA) subsystem
may verify the IMA signature of the kernel and initramfs, and measure
it. The command line parameters passed to the kernel in the kexec call
may also be measured by IMA. A remote attestation service can verify
a TPM quote based on the TPM event log, the IMA measurement list, and
the TPM PCR data. This can be achieved only if the IMA measurement log
is carried over from the current kernel to the next kernel across
the kexec call.
powerpc already supports carrying forward the IMA measurement log on
kexec. This patch set adds support for carrying forward the IMA
measurement log on kexec on ARM64.
This patch set moves the platform independent code defined for powerpc
such that it can be reused for other platforms as well. A chosen node
"linux,ima-kexec-buffer" is added to the DTB for ARM64 to hold
the address and the size of the memory reserved to carry
the IMA measurement log.
This patch set has been tested for ARM64 platform using QEMU.
I would like help from the community for testing this change on powerpc.
Thanks.
This patch set is based on
commit b3f82afc1041 ("IMA: Measure kernel version in early boot")
in https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git
"next-integrity" branch.
Changelog:
v16
- Defined functions to allocate and free buffer for FDT for powerpc
and arm64.
- Moved ima_buffer_addr and ima_buffer_size fields from
"struct kimage_arch" in powerpc to "struct kimage"
v15
- Included Rob's patches in the patch set, and rebased
the changes to "next-integrity" branch.
- Allocate memory for DTB, on arm64, using kmalloc() instead of
vmalloc() to keep it consistent with powerpc implementation.
- Call of_kexec_setup_new_fdt() from setup_new_fdt_ppc64() and
remove setup_new_fdt() in the same patch to keep it bisect safe.
v14
- Select CONFIG_HAVE_IMA_KEXEC for CONFIG_KEXEC_FILE, for powerpc
and arm64, if CONFIG_IMA is enabled.
- Use IS_ENABLED() macro instead of "#ifdef" in remove_ima_buffer(),
ima_get_kexec_buffer(), and ima_free_kexec_buffer().
- Call of_kexec_setup_new_fdt() from setup_new_fdt_ppc64() and
remove setup_new_fdt() in "arch/powerpc/kexec/file_load.c".
v13
- Moved the arch independent functions to drivers/of/kexec.c
and then refactored the code.
- Moved arch_ima_add_kexec_buffer() to
security/integrity/ima/ima_kexec.c
v12
- Use fdt_appendprop_addrrange() in setup_ima_buffer()
to setup the IMA measurement list property in
the device tree.
- Moved architecture independent functions from
"arch/powerpc/kexec/ima.c" to "drivers/of/kexec."
- Deleted "arch/powerpc/kexec/ima.c" and
"arch/powerpc/include/asm/ima.h".
v11
- Rebased the changes on the kexec code refactoring done by
Rob Herring in his "dt/kexec" branch
- Removed "extern" keyword in function declarations
- Removed unnecessary header files included in C files
- Updated patch descriptions per Thiago's comments
v10
- Moved delete_fdt_mem_rsv(), remove_ima_buffer(),
get_ima_kexec_buffer, and get_root_addr_size_cells()
to drivers/of/kexec.c
- Moved arch_ima_add_kexec_buffer() to
security/integrity/ima/ima_kexec.c
- Conditionally define IMA buffer fields in struct kimage_arch
v9
- Moved delete_fdt_mem_rsv() to drivers/of/kexec_fdt.c
- Defined a new function get_ima_kexec_buffer() in
drivers/of/ima_kexec.c to replace do_get_kexec_buffer()
- Changed remove_ima_kexec_buffer() to the original function name
remove_ima_buffer()
- Moved remove_ima_buffer() to drivers/of/ima_kexec.c
- Moved ima_get_kexec_buffer() and ima_free_kexec_buffer()
to security/integrity/ima/ima_kexec.c
v8:
- Moved remove_ima_kexec_buffer(), do_get_kexec_buffer(), and
delete_fdt_mem_rsv() to drivers/of/fdt.c
- Moved ima_dump_measurement_list() and ima_add_kexec_buffer()
back to security/integrity/ima/ima_kexec.c
v7:
- Renamed remove_ima_buffer() to remove_ima_kexec_buffer() and moved
this function definition to kernel.
- Moved delete_fdt_mem_rsv() definition to kernel
- Moved ima_dump_measurement_list() and ima_add_kexec_buffer() to
a new file namely ima_kexec_fdt.c in IMA
v6:
- Remove any existing FDT_PROP_IMA_KEXEC_BUFFER property in the device
tree and also its corresponding memory reservation in the currently
running kernel.
- Moved the function remove_ima_buffer() defined for powerpc to IMA
and renamed the function to ima_remove_kexec_buffer(). Also, moved
delete_fdt_mem_rsv() from powerpc to IMA.
v5:
- Merged get_addr_size_cells() and do_get_kexec_buffer() into a single
function when moving the arch independent code from powerpc to IMA
- Reverted the change to use FDT functions in powerpc code and added
back the original code in get_addr_size_cells() and
do_get_kexec_buffer() for powerpc.
- Added fdt_add_mem_rsv() for ARM64 to reserve the memory for
the IMA log buffer during kexec.
- Fixed the warning reported by kernel test bot for ARM64
arch_ima_add_kexec_buffer() - moved this function to a new file
namely arch/arm64/kernel/ima_kexec.c
v4:
- Submitting the patch series on behalf of the original author
Prakhar Srivastava <prsriva@linux.microsoft.com>
- Moved FDT_PROP_IMA_KEXEC_BUFFER ("linux,ima-kexec-buffer") to
libfdt.h so that it can be shared by multiple platforms.
v3:
Breakup patches further into separate patches.
- Refactoring non architecture specific code out of powerpc
- Update powerpc related code to use fdt functions
- Update IMA buffer read related code to use of functions
- Add support to store the memory information of the IMA
measurement logs to be carried forward.
- Update the property strings to align with documented nodes
https://github.com/devicetree-org/dt-schema/pull/46
v2:
Break patches into separate patches.
- Powerpc related Refactoring
- Updating the docuemntation for chosen node
- Updating arm64 to support IMA buffer pass
v1:
Refactoring carrying over IMA measuremnet logs over Kexec. This patch
moves the non-architecture specific code out of powerpc and adds to
security/ima.(Suggested by Thiago)
Add Documentation regarding the ima-kexec-buffer node in the chosen
node documentation
v0:
Add a layer of abstraction to use the memory reserved by device tree
for ima buffer pass.
Add support for ima buffer pass using reserved memory for arm64 kexec.
Update the arch sepcific code path in kexec file load to store the
ima buffer in the reserved memory. The same reserved memory is read
on kexec or cold boot.
Lakshmi Ramasubramanian (8):
powerpc: Move ima buffer fields to struct kimage
powerpc: Move arch independent ima kexec functions to
drivers/of/kexec.c
kexec: Use fdt_appendprop_addrrange() to add ima buffer to FDT
powerpc: Delete unused function delete_fdt_mem_rsv()
of: Define functions to allocate and free FDT
arm64: Use OF alloc and free functions for FDT
powerpc: Use OF alloc and free for FDT
arm64: Enable passing IMA log to next kernel on kexec
Rob Herring (4):
powerpc: Rename kexec elfcorehdr_addr to elf_headers_mem
of: Add a common kexec FDT setup function
arm64: Use common of_kexec_setup_new_fdt()
powerpc: Use common of_kexec_setup_new_fdt()
arch/arm64/Kconfig | 1 +
arch/arm64/kernel/machine_kexec_file.c | 158 +-------
arch/powerpc/Kconfig | 2 +-
arch/powerpc/include/asm/ima.h | 30 --
arch/powerpc/include/asm/kexec.h | 11 +-
arch/powerpc/kexec/Makefile | 7 -
arch/powerpc/kexec/elf_64.c | 26 +-
arch/powerpc/kexec/file_load.c | 184 +---------
arch/powerpc/kexec/file_load_64.c | 11 +-
arch/powerpc/kexec/ima.c | 219 -----------
drivers/of/Makefile | 1 +
drivers/of/kexec.c | 488 +++++++++++++++++++++++++
include/linux/kexec.h | 5 +
include/linux/of.h | 15 +-
security/integrity/ima/ima.h | 4 -
security/integrity/ima/ima_kexec.c | 3 +-
16 files changed, 552 insertions(+), 613 deletions(-)
delete mode 100644 arch/powerpc/include/asm/ima.h
delete mode 100644 arch/powerpc/kexec/ima.c
create mode 100644 drivers/of/kexec.c
--
2.30.0
^ permalink raw reply
* [PATCH v16 01/12] powerpc: Rename kexec elfcorehdr_addr to elf_headers_mem
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
From: Rob Herring <robh@kernel.org>
The architecture specific field, elfcorehdr_addr in struct kimage_arch,
that holds the address of the buffer in memory for ELF core header for
powerpc has a different name than the one used for arm64. This makes
it hard to have a common code for setting up the device tree for
kexec system call.
Rename elfcorehdr_addr to elf_headers_mem to align with arm64 name so
common code can use it.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
arch/powerpc/include/asm/kexec.h | 2 +-
arch/powerpc/kexec/file_load.c | 4 ++--
arch/powerpc/kexec/file_load_64.c | 4 ++--
3 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index 55d6ede30c19..dbf09d2f36d0 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -108,7 +108,7 @@ struct kimage_arch {
unsigned long backup_start;
void *backup_buf;
- unsigned long elfcorehdr_addr;
+ unsigned long elf_headers_mem;
unsigned long elf_headers_sz;
void *elf_headers;
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
index 9a232bc36c8f..e452b11df631 100644
--- a/arch/powerpc/kexec/file_load.c
+++ b/arch/powerpc/kexec/file_load.c
@@ -45,7 +45,7 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
return NULL;
elfcorehdr_strlen = sprintf(cmdline_ptr, "elfcorehdr=0x%lx ",
- image->arch.elfcorehdr_addr);
+ image->arch.elf_headers_mem);
if (elfcorehdr_strlen + cmdline_len > COMMAND_LINE_SIZE) {
pr_err("Appending elfcorehdr=<addr> exceeds cmdline size\n");
@@ -263,7 +263,7 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
* Avoid elfcorehdr from being stomped on in kdump kernel by
* setting up memory reserve map.
*/
- ret = fdt_add_mem_rsv(fdt, image->arch.elfcorehdr_addr,
+ ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
image->arch.elf_headers_sz);
if (ret) {
pr_err("Error reserving elfcorehdr memory: %s\n",
diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
index c69bcf9b547a..a05c19b3cc60 100644
--- a/arch/powerpc/kexec/file_load_64.c
+++ b/arch/powerpc/kexec/file_load_64.c
@@ -815,7 +815,7 @@ static int load_elfcorehdr_segment(struct kimage *image, struct kexec_buf *kbuf)
goto out;
}
- image->arch.elfcorehdr_addr = kbuf->mem;
+ image->arch.elf_headers_mem = kbuf->mem;
image->arch.elf_headers_sz = headers_sz;
image->arch.elf_headers = headers;
out:
@@ -851,7 +851,7 @@ int load_crashdump_segments_ppc64(struct kimage *image,
return ret;
}
pr_debug("Loaded elf core header at 0x%lx, bufsz=0x%lx memsz=0x%lx\n",
- image->arch.elfcorehdr_addr, kbuf->bufsz, kbuf->memsz);
+ image->arch.elf_headers_mem, kbuf->bufsz, kbuf->memsz);
return 0;
}
--
2.30.0
^ permalink raw reply related
* [PATCH v16 02/12] of: Add a common kexec FDT setup function
From: Lakshmi Ramasubramanian @ 2021-02-04 16:41 UTC (permalink / raw)
To: zohar, bauerman, robh, takahiro.akashi, gregkh, will, joe,
catalin.marinas, mpe
Cc: mark.rutland, bhsharma, tao.li, paulus, vincenzo.frascino,
frowand.list, sashal, masahiroy, jmorris, linux-arm-kernel, serge,
devicetree, pasha.tatashin, prsriva, hsinyi, allison,
christophe.leroy, mbrugger, balajib, dmitry.kasatkin,
linux-kernel, james.morse, linux-integrity, linuxppc-dev
In-Reply-To: <20210204164135.29856-1-nramas@linux.microsoft.com>
From: Rob Herring <robh@kernel.org>
Both arm64 and powerpc do essentially the same FDT /chosen setup for
kexec. The differences are either omissions that arm64 should have
or additional properties that will be ignored. The setup code can be
combined and shared by both powerpc and arm64.
The differences relative to the arm64 version:
- If /chosen doesn't exist, it will be created (should never happen).
- Any old dtb and initrd reserved memory will be released.
- The new initrd and elfcorehdr are marked reserved.
- "linux,booted-from-kexec" is set.
The differences relative to the powerpc version:
- "kaslr-seed" and "rng-seed" may be set.
- "linux,elfcorehdr" is set.
- Any existing "linux,usable-memory-range" is removed.
Combine the code for setting up the /chosen node in the FDT and updating
the memory reservation for kexec, for powerpc and arm64, in
of_kexec_setup_new_fdt() and move it to "drivers/of/kexec.c".
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
drivers/of/Makefile | 1 +
drivers/of/kexec.c | 236 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/of.h | 4 +
3 files changed, 241 insertions(+)
create mode 100644 drivers/of/kexec.c
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index 6e1e5212f058..8ce11955afde 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -13,5 +13,6 @@ obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o
obj-$(CONFIG_OF_RESOLVE) += resolver.o
obj-$(CONFIG_OF_OVERLAY) += overlay.o
obj-$(CONFIG_OF_NUMA) += of_numa.o
+obj-$(CONFIG_KEXEC_FILE) += kexec.o
obj-$(CONFIG_OF_UNITTEST) += unittest-data/
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
new file mode 100644
index 000000000000..4afd3cc1c04a
--- /dev/null
+++ b/drivers/of/kexec.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 Arm Limited
+ *
+ * Based on arch/arm64/kernel/machine_kexec_file.c:
+ * Copyright (C) 2018 Linaro Limited
+ *
+ * And arch/powerpc/kexec/file_load.c:
+ * Copyright (C) 2016 IBM Corporation
+ */
+
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/libfdt.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/random.h>
+#include <linux/types.h>
+
+/* relevant device tree properties */
+#define FDT_PROP_KEXEC_ELFHDR "linux,elfcorehdr"
+#define FDT_PROP_MEM_RANGE "linux,usable-memory-range"
+#define FDT_PROP_INITRD_START "linux,initrd-start"
+#define FDT_PROP_INITRD_END "linux,initrd-end"
+#define FDT_PROP_BOOTARGS "bootargs"
+#define FDT_PROP_KASLR_SEED "kaslr-seed"
+#define FDT_PROP_RNG_SEED "rng-seed"
+#define RNG_SEED_SIZE 128
+
+/**
+ * fdt_find_and_del_mem_rsv - delete memory reservation with given address and size
+ *
+ * @fdt: Flattened device tree for the current kernel.
+ * @start: Starting address of the reserved memory.
+ * @size: Size of the reserved memory.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned long size)
+{
+ int i, ret, num_rsvs = fdt_num_mem_rsv(fdt);
+
+ for (i = 0; i < num_rsvs; i++) {
+ u64 rsv_start, rsv_size;
+
+ ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
+ if (ret) {
+ pr_err("Malformed device tree.\n");
+ return -EINVAL;
+ }
+
+ if (rsv_start == start && rsv_size == size) {
+ ret = fdt_del_mem_rsv(fdt, i);
+ if (ret) {
+ pr_err("Error deleting device tree reservation.\n");
+ return -EINVAL;
+ }
+
+ return 0;
+ }
+ }
+
+ return -ENOENT;
+}
+
+/*
+ * of_kexec_setup_new_fdt - modify /chosen and memory reservation for the next kernel
+ *
+ * @image: kexec image being loaded.
+ * @fdt: Flattened device tree for the next kernel.
+ * @initrd_load_addr: Address where the next initrd will be loaded.
+ * @initrd_len: Size of the next initrd, or 0 if there will be none.
+ * @cmdline: Command line for the next kernel, or NULL if there will
+ * be none.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
+ unsigned long initrd_load_addr, unsigned long initrd_len,
+ const char *cmdline)
+{
+ int ret, chosen_node;
+ const void *prop;
+
+ /* Remove memory reservation for the current device tree. */
+ ret = fdt_find_and_del_mem_rsv(fdt, __pa(initial_boot_params),
+ fdt_totalsize(initial_boot_params));
+ if (ret == -EINVAL)
+ return ret;
+
+ chosen_node = fdt_path_offset(fdt, "/chosen");
+ if (chosen_node == -FDT_ERR_NOTFOUND)
+ chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
+ "chosen");
+ if (chosen_node < 0) {
+ ret = chosen_node;
+ goto out;
+ }
+
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_KEXEC_ELFHDR);
+ if (ret && ret != -FDT_ERR_NOTFOUND)
+ goto out;
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_MEM_RANGE);
+ if (ret && ret != -FDT_ERR_NOTFOUND)
+ goto out;
+
+ /* Did we boot using an initrd? */
+ prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
+ if (prop) {
+ u64 tmp_start, tmp_end, tmp_size;
+
+ tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
+
+ prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
+ if (!prop)
+ return -EINVAL;
+
+ tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
+
+ /*
+ * kexec reserves exact initrd size, while firmware may
+ * reserve a multiple of PAGE_SIZE, so check for both.
+ */
+ tmp_size = tmp_end - tmp_start;
+ ret = fdt_find_and_del_mem_rsv(fdt, tmp_start, tmp_size);
+ if (ret == -ENOENT)
+ ret = fdt_find_and_del_mem_rsv(fdt, tmp_start,
+ round_up(tmp_size, PAGE_SIZE));
+ if (ret == -EINVAL)
+ return ret;
+ }
+
+ /* add initrd-* */
+ if (initrd_load_addr) {
+ ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_START,
+ initrd_load_addr);
+ if (ret)
+ goto out;
+
+ ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_END,
+ initrd_load_addr + initrd_len);
+ if (ret)
+ goto out;
+
+ ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
+ if (ret)
+ goto out;
+
+ } else {
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_START);
+ if (ret && (ret != -FDT_ERR_NOTFOUND))
+ goto out;
+
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_END);
+ if (ret && (ret != -FDT_ERR_NOTFOUND))
+ goto out;
+ }
+
+ if (image->type == KEXEC_TYPE_CRASH) {
+ /* add linux,elfcorehdr */
+ ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+ FDT_PROP_KEXEC_ELFHDR,
+ image->arch.elf_headers_mem,
+ image->arch.elf_headers_sz);
+ if (ret)
+ goto out;
+
+ /*
+ * Avoid elfcorehdr from being stomped on in kdump kernel by
+ * setting up memory reserve map.
+ */
+ ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
+ image->arch.elf_headers_sz);
+ if (ret)
+ goto out;
+
+ /* add linux,usable-memory-range */
+ ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+ FDT_PROP_MEM_RANGE,
+ crashk_res.start,
+ crashk_res.end - crashk_res.start + 1);
+ if (ret)
+ goto out;
+ }
+
+ /* add bootargs */
+ if (cmdline) {
+ ret = fdt_setprop_string(fdt, chosen_node, FDT_PROP_BOOTARGS, cmdline);
+ if (ret)
+ goto out;
+ } else {
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_BOOTARGS);
+ if (ret && (ret != -FDT_ERR_NOTFOUND))
+ goto out;
+ }
+
+ /* add kaslr-seed */
+ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_KASLR_SEED);
+ if (ret == -FDT_ERR_NOTFOUND)
+ ret = 0;
+ else if (ret)
+ goto out;
+
+ if (rng_is_initialized()) {
+ u64 seed = get_random_u64();
+
+ ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_KASLR_SEED, seed);
+ if (ret)
+ goto out;
+ } else {
+ pr_notice("RNG is not initialised: omitting \"%s\" property\n",
+ FDT_PROP_KASLR_SEED);
+ }
+
+ /* add rng-seed */
+ if (rng_is_initialized()) {
+ void *rng_seed;
+
+ ret = fdt_setprop_placeholder(fdt, chosen_node, FDT_PROP_RNG_SEED,
+ RNG_SEED_SIZE, &rng_seed);
+ if (ret)
+ goto out;
+ get_random_bytes(rng_seed, RNG_SEED_SIZE);
+ } else {
+ pr_notice("RNG is not initialised: omitting \"%s\" property\n",
+ FDT_PROP_RNG_SEED);
+ }
+
+ ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+
+out:
+ if (ret)
+ return (ret == -FDT_ERR_NOSPACE) ? -ENOMEM : -EINVAL;
+
+ return 0;
+}
diff --git a/include/linux/of.h b/include/linux/of.h
index 4b27c9a27df3..41e256adf758 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -559,6 +559,10 @@ int of_map_id(struct device_node *np, u32 id,
struct device_node **target, u32 *id_out);
phys_addr_t of_dma_get_max_cpu_address(struct device_node *np);
+struct kimage;
+int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
+ unsigned long initrd_load_addr, unsigned long initrd_len,
+ const char *cmdline);
#else /* CONFIG_OF */
--
2.30.0
^ permalink raw reply related
* Re: [PATCH v2] powerpc/uprobes: Validation for prefixed instruction
From: Naveen N. Rao @ 2021-02-04 16:12 UTC (permalink / raw)
To: Ravi Bangoria
Cc: oleg, rostedt, linux-kernel, paulus, sandipan, jniethe5,
naveen.n.rao, linuxppc-dev
In-Reply-To: <20210204130821.GK210@DESKTOP-TDPLP67.localdomain>
On 2021/02/04 06:38PM, Naveen N. Rao wrote:
> On 2021/02/04 04:17PM, Ravi Bangoria wrote:
> > Don't allow Uprobe on 2nd word of a prefixed instruction. As per
> > ISA 3.1, prefixed instruction should not cross 64-byte boundary.
> > So don't allow Uprobe on such prefixed instruction as well.
> >
> > There are two ways probed instruction is changed in mapped pages.
> > First, when Uprobe is activated, it searches for all the relevant
> > pages and replace instruction in them. In this case, if we notice
> > that probe is on the 2nd word of prefixed instruction, error out
> > directly. Second, when Uprobe is already active and user maps a
> > relevant page via mmap(), instruction is replaced via mmap() code
> > path. But because Uprobe is invalid, entire mmap() operation can
> > not be stopped. In this case just print an error and continue.
> >
> > Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
> > ---
> > v1: http://lore.kernel.org/r/20210119091234.76317-1-ravi.bangoria@linux.ibm.com
> > v1->v2:
> > - Instead of introducing new arch hook from verify_opcode(), use
> > existing hook arch_uprobe_analyze_insn().
> > - Add explicit check for prefixed instruction crossing 64-byte
> > boundary. If probe is on such instruction, throw an error.
> >
> > arch/powerpc/kernel/uprobes.c | 66 ++++++++++++++++++++++++++++++++++-
> > 1 file changed, 65 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/powerpc/kernel/uprobes.c b/arch/powerpc/kernel/uprobes.c
> > index e8a63713e655..485d19a2a31f 100644
> > --- a/arch/powerpc/kernel/uprobes.c
> > +++ b/arch/powerpc/kernel/uprobes.c
> > @@ -7,6 +7,7 @@
> > * Adapted from the x86 port by Ananth N Mavinakayanahalli <ananth@in.ibm.com>
> > */
> > #include <linux/kernel.h>
> > +#include <linux/highmem.h>
> > #include <linux/sched.h>
> > #include <linux/ptrace.h>
> > #include <linux/uprobes.h>
> > @@ -28,6 +29,69 @@ bool is_trap_insn(uprobe_opcode_t *insn)
> > return (is_trap(*insn));
> > }
> >
> > +#ifdef CONFIG_PPC64
> > +static int get_instr(struct mm_struct *mm, unsigned long addr, u32 *instr)
> > +{
> > + struct page *page;
> > + struct vm_area_struct *vma;
> > + void *kaddr;
> > + unsigned int gup_flags = FOLL_FORCE | FOLL_SPLIT_PMD;
> > +
> > + if (get_user_pages_remote(mm, addr, 1, gup_flags, &page, &vma, NULL) <= 0)
> > + return -EINVAL;
> > +
> > + kaddr = kmap_atomic(page);
> > + *instr = *((u32 *)(kaddr + (addr & ~PAGE_MASK)));
> > + kunmap_atomic(kaddr);
> > + put_page(page);
> > + return 0;
> > +}
> > +
> > +static int validate_prefixed_instr(struct mm_struct *mm, unsigned long addr)
> > +{
> > + struct ppc_inst inst;
> > + u32 prefix, suffix;
> > +
> > + /*
> > + * No need to check if addr is pointing to beginning of the
> > + * page. Even if probe is on a suffix of page-unaligned
> > + * prefixed instruction, hw will raise exception and kernel
> > + * will send SIGBUS.
> > + */
> > + if (!(addr & ~PAGE_MASK))
> > + return 0;
> > +
> > + if (get_instr(mm, addr, &prefix) < 0)
> > + return -EINVAL;
> > + if (get_instr(mm, addr + 4, &suffix) < 0)
> > + return -EINVAL;
> > +
> > + inst = ppc_inst_prefix(prefix, suffix);
> > + if (ppc_inst_prefixed(inst) && (addr & 0x3F) == 0x3C) {
> > + printk_ratelimited("Cannot register a uprobe on 64 byte "
> ^^^^^^^^^^^^^^^^^^ pr_info_ratelimited()
>
> It should be sufficient to check the primary opcode to determine if it
> is a prefixed instruction. You don't have to read the suffix. I see that
> we don't have a helper to do this currently, so you could do:
>
> if (ppc_inst_primary_opcode(ppc_inst(prefix)) == 1)
Seeing the kprobes code, I realized that we have to check for another
scenario (Thanks, Jordan!). If this is the suffix of a prefix
instruction for which a uprobe has already been installed, then the
previous word will be a 'trap' instruction. You need to check if there
is a uprobe at the previous word, and if the original instruction there
was a prefix instruction.
- Naveen
^ permalink raw reply
* Re: [PATCH] vio: make remove callback return void
From: Greg Kroah-Hartman @ 2021-02-04 16:08 UTC (permalink / raw)
To: Uwe Kleine-König
Cc: Cristobal Forno, Tyrel Datwyler, sparclinux, target-devel,
Paul Mackerras, Breno Leitão, Peter Huewe,
Sukadev Bhattiprolu, Jiri Slaby, Herbert Xu, linux-scsi,
Nayna Jain, Jason Gunthorpe, Michael Cyr, Jakub Kicinski,
Arnd Bergmann, James E.J. Bottomley, linux-block, Lijun Pan,
Matt Mackall, Jens Axboe, Steven Royer, Martin K. Petersen,
netdev, linux-kernel, Jarkko Sakkinen, linux-crypto, Dany Madden,
Paulo Flabiano Smorigo, linux-integrity, linuxppc-dev,
David S. Miller
In-Reply-To: <20210127215010.99954-1-uwe@kleine-koenig.org>
On Wed, Jan 27, 2021 at 10:50:10PM +0100, Uwe Kleine-König wrote:
> The driver core ignores the return value of struct bus_type::remove()
> because there is only little that can be done. To simplify the quest to
> make this function return void, let struct vio_driver::remove() return
> void, too. All users already unconditionally return 0, this commit makes
> it obvious that returning an error code is a bad idea and makes it
> obvious for future driver authors that returning an error code isn't
> intended.
>
> Note there are two nominally different implementations for a vio bus:
> one in arch/sparc/kernel/vio.c and the other in
> arch/powerpc/platforms/pseries/vio.c. I didn't care to check which
> driver is using which of these busses (or if even some of them can be
> used with both) and simply adapt all drivers and the two bus codes in
> one go.
>
> Note that for the powerpc implementation there is a semantical change:
> Before this patch for a device that was bound to a driver without a
> remove callback vio_cmo_bus_remove(viodev) wasn't called. As the device
> core still considers the device unbound after vio_bus_remove() returns
> calling this unconditionally is the consistent behaviour which is
> implemented here.
>
> Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
> ---
> Hello,
>
> note that this change depends on
> https://lore.kernel.org/r/20210121062005.53271-1-ljp@linux.ibm.com which removes
> an (ignored) return -EBUSY in drivers/net/ethernet/ibm/ibmvnic.c.
> I don't know when/if this latter patch will be applied, so it might take
> some time until my patch can go in.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
^ permalink raw reply
* Re: [PATCH v2] powerpc/uprobes: Validation for prefixed instruction
From: Ananth N Mavinakayanahalli @ 2021-02-04 14:19 UTC (permalink / raw)
To: linuxppc-dev
In-Reply-To: <79b0bed7-8b98-d58d-dc47-644195bbc095@linux.ibm.com>
On 2/4/21 4:19 PM, Ravi Bangoria wrote:
>
>
> On 2/4/21 4:17 PM, Ravi Bangoria wrote:
>> Don't allow Uprobe on 2nd word of a prefixed instruction. As per
>> ISA 3.1, prefixed instruction should not cross 64-byte boundary.
>> So don't allow Uprobe on such prefixed instruction as well.
>>
>> There are two ways probed instruction is changed in mapped pages.
>> First, when Uprobe is activated, it searches for all the relevant
>> pages and replace instruction in them. In this case, if we notice
>> that probe is on the 2nd word of prefixed instruction, error out
>> directly. Second, when Uprobe is already active and user maps a
>> relevant page via mmap(), instruction is replaced via mmap() code
>> path. But because Uprobe is invalid, entire mmap() operation can
>> not be stopped. In this case just print an error and continue.
>
> @mpe,
>
> arch_uprobe_analyze_insn() can return early if
> cpu_has_feature(CPU_FTR_ARCH_31) is not set. But that will
> miss out a rare scenario of user running binary with prefixed
> instruction on p10 predecessors. Please let me know if I
> should add cpu_has_feature(CPU_FTR_ARCH_31) or not.
Wouldn't that binary get a SIGILL in any case? I concur with Naveen...
it makes sense to add the check.
--
Ananth
^ permalink raw reply
* Re: [PATCH v2] powerpc/uprobes: Validation for prefixed instruction
From: Naveen N. Rao @ 2021-02-04 13:15 UTC (permalink / raw)
To: Ravi Bangoria
Cc: oleg, rostedt, linux-kernel, paulus, sandipan, jniethe5,
naveen.n.rao, linuxppc-dev
In-Reply-To: <79b0bed7-8b98-d58d-dc47-644195bbc095@linux.ibm.com>
On 2021/02/04 04:19PM, Ravi Bangoria wrote:
>
>
> On 2/4/21 4:17 PM, Ravi Bangoria wrote:
> > Don't allow Uprobe on 2nd word of a prefixed instruction. As per
> > ISA 3.1, prefixed instruction should not cross 64-byte boundary.
> > So don't allow Uprobe on such prefixed instruction as well.
> >
> > There are two ways probed instruction is changed in mapped pages.
> > First, when Uprobe is activated, it searches for all the relevant
> > pages and replace instruction in them. In this case, if we notice
> > that probe is on the 2nd word of prefixed instruction, error out
> > directly. Second, when Uprobe is already active and user maps a
> > relevant page via mmap(), instruction is replaced via mmap() code
> > path. But because Uprobe is invalid, entire mmap() operation can
> > not be stopped. In this case just print an error and continue.
>
> @mpe,
>
> arch_uprobe_analyze_insn() can return early if
> cpu_has_feature(CPU_FTR_ARCH_31) is not set. But that will
> miss out a rare scenario of user running binary with prefixed
> instruction on p10 predecessors. Please let me know if I
> should add cpu_has_feature(CPU_FTR_ARCH_31) or not.
The check you are adding is very specific to prefixed instructions, so
it makes sense to add a cpu feature check for v3.1.
On older processors, those are invalid instructions like any other. The
instruction emulation infrastructure will refuse to emulate it and the
instruction will be single stepped.
- Naveen
^ permalink raw reply
* Re: [PATCH v2] powerpc/uprobes: Validation for prefixed instruction
From: Naveen N. Rao @ 2021-02-04 13:08 UTC (permalink / raw)
To: Ravi Bangoria
Cc: oleg, rostedt, linux-kernel, paulus, sandipan, jniethe5,
naveen.n.rao, linuxppc-dev
In-Reply-To: <20210204104703.273429-1-ravi.bangoria@linux.ibm.com>
On 2021/02/04 04:17PM, Ravi Bangoria wrote:
> Don't allow Uprobe on 2nd word of a prefixed instruction. As per
> ISA 3.1, prefixed instruction should not cross 64-byte boundary.
> So don't allow Uprobe on such prefixed instruction as well.
>
> There are two ways probed instruction is changed in mapped pages.
> First, when Uprobe is activated, it searches for all the relevant
> pages and replace instruction in them. In this case, if we notice
> that probe is on the 2nd word of prefixed instruction, error out
> directly. Second, when Uprobe is already active and user maps a
> relevant page via mmap(), instruction is replaced via mmap() code
> path. But because Uprobe is invalid, entire mmap() operation can
> not be stopped. In this case just print an error and continue.
>
> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
> ---
> v1: http://lore.kernel.org/r/20210119091234.76317-1-ravi.bangoria@linux.ibm.com
> v1->v2:
> - Instead of introducing new arch hook from verify_opcode(), use
> existing hook arch_uprobe_analyze_insn().
> - Add explicit check for prefixed instruction crossing 64-byte
> boundary. If probe is on such instruction, throw an error.
>
> arch/powerpc/kernel/uprobes.c | 66 ++++++++++++++++++++++++++++++++++-
> 1 file changed, 65 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/kernel/uprobes.c b/arch/powerpc/kernel/uprobes.c
> index e8a63713e655..485d19a2a31f 100644
> --- a/arch/powerpc/kernel/uprobes.c
> +++ b/arch/powerpc/kernel/uprobes.c
> @@ -7,6 +7,7 @@
> * Adapted from the x86 port by Ananth N Mavinakayanahalli <ananth@in.ibm.com>
> */
> #include <linux/kernel.h>
> +#include <linux/highmem.h>
> #include <linux/sched.h>
> #include <linux/ptrace.h>
> #include <linux/uprobes.h>
> @@ -28,6 +29,69 @@ bool is_trap_insn(uprobe_opcode_t *insn)
> return (is_trap(*insn));
> }
>
> +#ifdef CONFIG_PPC64
> +static int get_instr(struct mm_struct *mm, unsigned long addr, u32 *instr)
> +{
> + struct page *page;
> + struct vm_area_struct *vma;
> + void *kaddr;
> + unsigned int gup_flags = FOLL_FORCE | FOLL_SPLIT_PMD;
> +
> + if (get_user_pages_remote(mm, addr, 1, gup_flags, &page, &vma, NULL) <= 0)
> + return -EINVAL;
> +
> + kaddr = kmap_atomic(page);
> + *instr = *((u32 *)(kaddr + (addr & ~PAGE_MASK)));
> + kunmap_atomic(kaddr);
> + put_page(page);
> + return 0;
> +}
> +
> +static int validate_prefixed_instr(struct mm_struct *mm, unsigned long addr)
> +{
> + struct ppc_inst inst;
> + u32 prefix, suffix;
> +
> + /*
> + * No need to check if addr is pointing to beginning of the
> + * page. Even if probe is on a suffix of page-unaligned
> + * prefixed instruction, hw will raise exception and kernel
> + * will send SIGBUS.
> + */
> + if (!(addr & ~PAGE_MASK))
> + return 0;
> +
> + if (get_instr(mm, addr, &prefix) < 0)
> + return -EINVAL;
> + if (get_instr(mm, addr + 4, &suffix) < 0)
> + return -EINVAL;
> +
> + inst = ppc_inst_prefix(prefix, suffix);
> + if (ppc_inst_prefixed(inst) && (addr & 0x3F) == 0x3C) {
> + printk_ratelimited("Cannot register a uprobe on 64 byte "
^^^^^^^^^^^^^^^^^^ pr_info_ratelimited()
It should be sufficient to check the primary opcode to determine if it
is a prefixed instruction. You don't have to read the suffix. I see that
we don't have a helper to do this currently, so you could do:
if (ppc_inst_primary_opcode(ppc_inst(prefix)) == 1)
In the future, it might be worthwhile to add IS_PREFIX() as a macro
similar to IS_MTMSRD() if there are more such uses.
Along with this, if you also add the below to the start of this
function, you can get rid of the #ifdef:
if (!IS_ENABLED(CONFIG_PPC64))
return 0;
- Naveen
^ permalink raw reply
* [PATCH kernel v3] powerpc/uaccess: Skip might_fault() when user access is enabled
From: Alexey Kardashevskiy @ 2021-02-04 12:16 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Alexey Kardashevskiy, Jordan Niethe, Nicholas Piggin
The amount of code executed with enabled user space access (unlocked KUAP)
should be minimal. However with CONFIG_PROVE_LOCKING or
CONFIG_DEBUG_ATOMIC_SLEEP enabled, might_fault() may end up replaying
interrupts which in turn may access the user space and forget to restore
the KUAP state.
The problem places are:
1. strncpy_from_user (and similar) which unlock KUAP and call
unsafe_get_user -> __get_user_allowed -> __get_user_nocheck()
with do_allow=false to skip KUAP as the caller took care of it.
2. __put_user_nocheck_goto() which is called with unlocked KUAP.
This changes __get_user_nocheck() to look at @do_allow to decide whether
to skip might_fault(). Since strncpy_from_user/etc call might_fault()
anyway before unlocking KUAP, there should be no visible change.
This drops might_fault() in __put_user_nocheck_goto() as it is only
called from unsafe_xxx helpers which manage KUAP themselves.
Since keeping might_fault() is still desireable, this adds those
to user_access_begin/read/write which is the last point where
we can safely do so.
Fixes: 334710b1496a ("powerpc/uaccess: Implement unsafe_put_user() using 'asm goto'")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
Changes:
v3:
* removed might_fault() from __put_user_nocheck_goto
* added might_fault() to user(_|_read_|_write_)access_begin
v2:
* s/!do_allow/do_allow/
---
Here is more detail about the issue:
https://lore.kernel.org/linuxppc-dev/20210203084503.GX6564@kitsune.suse.cz/T/
Another example of the problem:
Kernel attempted to write user page (200002c3) - exploit attempt? (uid: 0)
------------[ cut here ]------------
Bug: Write fault blocked by KUAP!
WARNING: CPU: 1 PID: 16712 at /home/aik/p/kernel-syzkaller/arch/powerpc/mm/fault.c:229 __do_page_fault+0xca4/0xf10
NIP [c0000000006ff804] filldir64+0x484/0x820
LR [c0000000006ff7fc] filldir64+0x47c/0x820
--- interrupt: 300
[c0000000589f3b40] [c0000000008131b0] proc_fill_cache+0xf0/0x2b0
[c0000000589f3c60] [c000000000814658] proc_pident_readdir+0x1f8/0x390
[c0000000589f3cc0] [c0000000006fd8e8] iterate_dir+0x108/0x370
[c0000000589f3d20] [c0000000006fe3d8] sys_getdents64+0xa8/0x410
[c0000000589f3db0] [c00000000004b708] system_call_exception+0x178/0x2b0
[c0000000589f3e10] [c00000000000e060] system_call_common+0xf0/0x27c
---
arch/powerpc/include/asm/uaccess.h | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 501c9a79038c..a789601998d3 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -216,8 +216,6 @@ do { \
#define __put_user_nocheck_goto(x, ptr, size, label) \
do { \
__typeof__(*(ptr)) __user *__pu_addr = (ptr); \
- if (!is_kernel_addr((unsigned long)__pu_addr)) \
- might_fault(); \
__chk_user_ptr(ptr); \
__put_user_size_goto((x), __pu_addr, (size), label); \
} while (0)
@@ -313,7 +311,7 @@ do { \
__typeof__(size) __gu_size = (size); \
\
__chk_user_ptr(__gu_addr); \
- if (!is_kernel_addr((unsigned long)__gu_addr)) \
+ if (do_allow && !is_kernel_addr((unsigned long)__gu_addr)) \
might_fault(); \
barrier_nospec(); \
if (do_allow) \
@@ -508,6 +506,8 @@ static __must_check inline bool user_access_begin(const void __user *ptr, size_t
{
if (unlikely(!access_ok(ptr, len)))
return false;
+ if (!is_kernel_addr((unsigned long)ptr))
+ might_fault();
allow_read_write_user((void __user *)ptr, ptr, len);
return true;
}
@@ -521,6 +521,8 @@ user_read_access_begin(const void __user *ptr, size_t len)
{
if (unlikely(!access_ok(ptr, len)))
return false;
+ if (!is_kernel_addr((unsigned long)ptr))
+ might_fault();
allow_read_from_user(ptr, len);
return true;
}
@@ -532,6 +534,8 @@ user_write_access_begin(const void __user *ptr, size_t len)
{
if (unlikely(!access_ok(ptr, len)))
return false;
+ if (!is_kernel_addr((unsigned long)ptr))
+ might_fault();
allow_write_to_user((void __user *)ptr, len);
return true;
}
--
2.17.1
^ permalink raw reply related
* Re: [PATCH 3/3] tools/perf: Add perf tools support to expose Performance Monitor Counter SPRs as part of extended regs
From: Athira Rajeev @ 2021-02-04 12:14 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo; +Cc: kjain, Madhavan Srinivasan, linuxppc-dev, jolsa
In-Reply-To: <20210203162520.GG854763@kernel.org>
> On 03-Feb-2021, at 9:55 PM, Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
>
> Em Wed, Feb 03, 2021 at 01:55:37AM -0500, Athira Rajeev escreveu:
>> To enable presenting of Performance Monitor Counter Registers
>> (PMC1 to PMC6) as part of extended regsiters, patch adds these
>> to sample_reg_mask in the tool side (to use with -I? option).
>>
>> Simplified the PERF_REG_PMU_MASK_300/31 definition. Excluded the
>> unsupported SPRs (MMCR3, SIER2, SIER3) from extended mask value for
>> CPU_FTR_ARCH_300.
>
> Applied just 3/3, the tooling part, to my local branch, please holler if
> I should wait a bit more.
>
> - Arnaldo
>
Thanks Arnaldo for taking the tool side changes.
Athira.
>> Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
>> ---
>> tools/arch/powerpc/include/uapi/asm/perf_regs.h | 28 +++++++++++++++++++------
>> tools/perf/arch/powerpc/include/perf_regs.h | 6 ++++++
>> tools/perf/arch/powerpc/util/perf_regs.c | 6 ++++++
>> 3 files changed, 34 insertions(+), 6 deletions(-)
>>
>> diff --git a/tools/arch/powerpc/include/uapi/asm/perf_regs.h b/tools/arch/powerpc/include/uapi/asm/perf_regs.h
>> index bdf5f10f8b9f..578b3ee86105 100644
>> --- a/tools/arch/powerpc/include/uapi/asm/perf_regs.h
>> +++ b/tools/arch/powerpc/include/uapi/asm/perf_regs.h
>> @@ -55,17 +55,33 @@ enum perf_event_powerpc_regs {
>> PERF_REG_POWERPC_MMCR3,
>> PERF_REG_POWERPC_SIER2,
>> PERF_REG_POWERPC_SIER3,
>> + PERF_REG_POWERPC_PMC1,
>> + PERF_REG_POWERPC_PMC2,
>> + PERF_REG_POWERPC_PMC3,
>> + PERF_REG_POWERPC_PMC4,
>> + PERF_REG_POWERPC_PMC5,
>> + PERF_REG_POWERPC_PMC6,
>> /* Max regs without the extended regs */
>> PERF_REG_POWERPC_MAX = PERF_REG_POWERPC_MMCRA + 1,
>> };
>>
>> #define PERF_REG_PMU_MASK ((1ULL << PERF_REG_POWERPC_MAX) - 1)
>>
>> -/* PERF_REG_EXTENDED_MASK value for CPU_FTR_ARCH_300 */
>> -#define PERF_REG_PMU_MASK_300 (((1ULL << (PERF_REG_POWERPC_MMCR2 + 1)) - 1) - PERF_REG_PMU_MASK)
>> -/* PERF_REG_EXTENDED_MASK value for CPU_FTR_ARCH_31 */
>> -#define PERF_REG_PMU_MASK_31 (((1ULL << (PERF_REG_POWERPC_SIER3 + 1)) - 1) - PERF_REG_PMU_MASK)
>> +/* Exclude MMCR3, SIER2, SIER3 for CPU_FTR_ARCH_300 */
>> +#define PERF_EXCLUDE_REG_EXT_300 (7ULL << PERF_REG_POWERPC_MMCR3)
>>
>> -#define PERF_REG_MAX_ISA_300 (PERF_REG_POWERPC_MMCR2 + 1)
>> -#define PERF_REG_MAX_ISA_31 (PERF_REG_POWERPC_SIER3 + 1)
>> +/*
>> + * PERF_REG_EXTENDED_MASK value for CPU_FTR_ARCH_300
>> + * includes 9 SPRS from MMCR0 to PMC6 excluding the
>> + * unsupported SPRS in PERF_EXCLUDE_REG_EXT_300.
>> + */
>> +#define PERF_REG_PMU_MASK_300 ((0xfffULL << PERF_REG_POWERPC_MMCR0) - PERF_EXCLUDE_REG_EXT_300)
>> +
>> +/*
>> + * PERF_REG_EXTENDED_MASK value for CPU_FTR_ARCH_31
>> + * includes 12 SPRs from MMCR0 to PMC6.
>> + */
>> +#define PERF_REG_PMU_MASK_31 (0xfffULL << PERF_REG_POWERPC_MMCR0)
>> +
>> +#define PERF_REG_EXTENDED_MAX (PERF_REG_POWERPC_PMC6 + 1)
>> #endif /* _UAPI_ASM_POWERPC_PERF_REGS_H */
>> diff --git a/tools/perf/arch/powerpc/include/perf_regs.h b/tools/perf/arch/powerpc/include/perf_regs.h
>> index 63f3ac91049f..98b6f9eabfc3 100644
>> --- a/tools/perf/arch/powerpc/include/perf_regs.h
>> +++ b/tools/perf/arch/powerpc/include/perf_regs.h
>> @@ -71,6 +71,12 @@
>> [PERF_REG_POWERPC_MMCR3] = "mmcr3",
>> [PERF_REG_POWERPC_SIER2] = "sier2",
>> [PERF_REG_POWERPC_SIER3] = "sier3",
>> + [PERF_REG_POWERPC_PMC1] = "pmc1",
>> + [PERF_REG_POWERPC_PMC2] = "pmc2",
>> + [PERF_REG_POWERPC_PMC3] = "pmc3",
>> + [PERF_REG_POWERPC_PMC4] = "pmc4",
>> + [PERF_REG_POWERPC_PMC5] = "pmc5",
>> + [PERF_REG_POWERPC_PMC6] = "pmc6",
>> };
>>
>> static inline const char *perf_reg_name(int id)
>> diff --git a/tools/perf/arch/powerpc/util/perf_regs.c b/tools/perf/arch/powerpc/util/perf_regs.c
>> index 2b6d4704e3aa..8116a253f91f 100644
>> --- a/tools/perf/arch/powerpc/util/perf_regs.c
>> +++ b/tools/perf/arch/powerpc/util/perf_regs.c
>> @@ -68,6 +68,12 @@
>> SMPL_REG(mmcr3, PERF_REG_POWERPC_MMCR3),
>> SMPL_REG(sier2, PERF_REG_POWERPC_SIER2),
>> SMPL_REG(sier3, PERF_REG_POWERPC_SIER3),
>> + SMPL_REG(pmc1, PERF_REG_POWERPC_PMC1),
>> + SMPL_REG(pmc2, PERF_REG_POWERPC_PMC2),
>> + SMPL_REG(pmc3, PERF_REG_POWERPC_PMC3),
>> + SMPL_REG(pmc4, PERF_REG_POWERPC_PMC4),
>> + SMPL_REG(pmc5, PERF_REG_POWERPC_PMC5),
>> + SMPL_REG(pmc6, PERF_REG_POWERPC_PMC6),
>> SMPL_REG_END
>> };
>>
>> --
>> 1.8.3.1
>>
>
> --
>
> - Arnaldo
^ permalink raw reply
* Re: [PATCH] tools/perf: Fix powerpc gap between kernel end and module start
From: Athira Rajeev @ 2021-02-04 12:11 UTC (permalink / raw)
To: Arnaldo Carvalho de Melo
Cc: linuxppc-dev, Madhavan Srinivasan, Jiri Olsa, Jiri Olsa,
Kajol Jain
In-Reply-To: <20210203153148.GC854763@kernel.org>
> On 03-Feb-2021, at 9:01 PM, Arnaldo Carvalho de Melo <acme@kernel.org> wrote:
>
> Thanks, collected the Tested-by from Kajol and the Acked-by from Jiri
> and applied to my local tree for testing, then up to my perf/core
> branch.
>
> - Arnaldo
Thanks Arnaldo for taking this fix.
^ permalink raw reply
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