From: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
To: "broonie@kernel.org" <broonie@kernel.org>,
"Szabolcs.Nagy@arm.com" <Szabolcs.Nagy@arm.com>
Cc: "corbet@lwn.net" <corbet@lwn.net>,
"ardb@kernel.org" <ardb@kernel.org>,
"maz@kernel.org" <maz@kernel.org>,
"shuah@kernel.org" <shuah@kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"keescook@chromium.org" <keescook@chromium.org>,
"james.morse@arm.com" <james.morse@arm.com>,
"debug@rivosinc.com" <debug@rivosinc.com>,
"akpm@linux-foundation.org" <akpm@linux-foundation.org>,
"palmer@dabbelt.com" <palmer@dabbelt.com>,
"catalin.marinas@arm.com" <catalin.marinas@arm.com>,
"hjl.tools@gmail.com" <hjl.tools@gmail.com>,
"paul.walmsley@sifive.com" <paul.walmsley@sifive.com>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
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Subject: Re: [PATCH 22/35] arm64/mm: Implement map_shadow_stack()
Date: Tue, 18 Jul 2023 15:49:28 +0000 [thread overview]
Message-ID: <7a4c97f68347d4188286c543cdccaa12577cdb9e.camel@intel.com> (raw)
In-Reply-To: <8ea03eda-e630-40c5-acc1-a63f5c5b3102@sirena.org.uk>
On Tue, 2023-07-18 at 14:55 +0100, Mark Brown wrote:
> On Tue, Jul 18, 2023 at 10:10:04AM +0100, Szabolcs Nagy wrote:
>
> > uint64_t *p = map_shadow_stack(0, N*8, 0);
>
> > i'd expect p[N-1] to be the end token and p[N-2] to be the cap
> > token,
> > not p[PAGE_ALIGN(N*8)/8-2].
>
> Yes, that probably would be more helpful.
HJ made a similar request on the x86 side. He wanted an unaligned size
passed in to result in unaligned token placement.
>
> > if we allow misalligned size here (and in munmap) then i think it's
> > better to not page align. size%8!=0 || size<16 can be an error.
>
> Honestly I'd be a lot happier to just not allow misalignment but that
> raises the issue with binaries randomly not working when moved to a
> kernel with a different page size. I'll have a think but possibly
> the
> safest thing would be requiring a multiple of 4K then rounding up to
> our
> actual page size.
Someday when the x86 side is finally upstream I have a manpage for
map_shadow_stack. Any differences on the arm side would need to be
documented, but I'm not sure why there should be any differences. Like,
why not use the same flags? Or have a new flag for token+end marker
that x86 can use as well?
WARNING: multiple messages have this Message-ID (diff)
From: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
To: "broonie@kernel.org" <broonie@kernel.org>,
"Szabolcs.Nagy@arm.com" <Szabolcs.Nagy@arm.com>
Cc: "corbet@lwn.net" <corbet@lwn.net>,
"ardb@kernel.org" <ardb@kernel.org>,
"maz@kernel.org" <maz@kernel.org>,
"shuah@kernel.org" <shuah@kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"keescook@chromium.org" <keescook@chromium.org>,
"james.morse@arm.com" <james.morse@arm.com>,
"debug@rivosinc.com" <debug@rivosinc.com>,
"akpm@linux-foundation.org" <akpm@linux-foundation.org>,
"palmer@dabbelt.com" <palmer@dabbelt.com>,
"catalin.marinas@arm.com" <catalin.marinas@arm.com>,
"hjl.tools@gmail.com" <hjl.tools@gmail.com>,
"paul.walmsley@sifive.com" <paul.walmsley@sifive.com>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
"aou@eecs.berkeley.edu" <aou@eecs.berkeley.edu>,
"oleg@redhat.com" <oleg@redhat.com>,
"arnd@arndb.de" <arnd@arndb.de>,
"ebiederm@xmission.com" <ebiederm@xmission.com>,
"will@kernel.org" <will@kernel.org>,
"suzuki.poulose@arm.com" <suzuki.poulose@arm.com>,
"kvmarm@lists.linux.dev" <kvmarm@lists.linux.dev>,
"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>,
"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
"linux-kselftest@vger.kernel.org"
<linux-kselftest@vger.kernel.org>,
"linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
"oliver.upton@linux.dev" <oliver.upton@linux.dev>,
"linux-riscv@lists.infradead.org"
<linux-riscv@lists.infradead.org>
Subject: Re: [PATCH 22/35] arm64/mm: Implement map_shadow_stack()
Date: Tue, 18 Jul 2023 15:49:28 +0000 [thread overview]
Message-ID: <7a4c97f68347d4188286c543cdccaa12577cdb9e.camel@intel.com> (raw)
In-Reply-To: <8ea03eda-e630-40c5-acc1-a63f5c5b3102@sirena.org.uk>
On Tue, 2023-07-18 at 14:55 +0100, Mark Brown wrote:
> On Tue, Jul 18, 2023 at 10:10:04AM +0100, Szabolcs Nagy wrote:
>
> > uint64_t *p = map_shadow_stack(0, N*8, 0);
>
> > i'd expect p[N-1] to be the end token and p[N-2] to be the cap
> > token,
> > not p[PAGE_ALIGN(N*8)/8-2].
>
> Yes, that probably would be more helpful.
HJ made a similar request on the x86 side. He wanted an unaligned size
passed in to result in unaligned token placement.
>
> > if we allow misalligned size here (and in munmap) then i think it's
> > better to not page align. size%8!=0 || size<16 can be an error.
>
> Honestly I'd be a lot happier to just not allow misalignment but that
> raises the issue with binaries randomly not working when moved to a
> kernel with a different page size. I'll have a think but possibly
> the
> safest thing would be requiring a multiple of 4K then rounding up to
> our
> actual page size.
Someday when the x86 side is finally upstream I have a manpage for
map_shadow_stack. Any differences on the arm side would need to be
documented, but I'm not sure why there should be any differences. Like,
why not use the same flags? Or have a new flag for token+end marker
that x86 can use as well?
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv
WARNING: multiple messages have this Message-ID (diff)
From: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
To: "broonie@kernel.org" <broonie@kernel.org>,
"Szabolcs.Nagy@arm.com" <Szabolcs.Nagy@arm.com>
Cc: "corbet@lwn.net" <corbet@lwn.net>,
"ardb@kernel.org" <ardb@kernel.org>,
"maz@kernel.org" <maz@kernel.org>,
"shuah@kernel.org" <shuah@kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"keescook@chromium.org" <keescook@chromium.org>,
"james.morse@arm.com" <james.morse@arm.com>,
"debug@rivosinc.com" <debug@rivosinc.com>,
"akpm@linux-foundation.org" <akpm@linux-foundation.org>,
"palmer@dabbelt.com" <palmer@dabbelt.com>,
"catalin.marinas@arm.com" <catalin.marinas@arm.com>,
"hjl.tools@gmail.com" <hjl.tools@gmail.com>,
"paul.walmsley@sifive.com" <paul.walmsley@sifive.com>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
"aou@eecs.berkeley.edu" <aou@eecs.berkeley.edu>,
"oleg@redhat.com" <oleg@redhat.com>,
"arnd@arndb.de" <arnd@arndb.de>,
"ebiederm@xmission.com" <ebiederm@xmission.com>,
"will@kernel.org" <will@kernel.org>,
"suzuki.poulose@arm.com" <suzuki.poulose@arm.com>,
"kvmarm@lists.linux.dev" <kvmarm@lists.linux.dev>,
"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>,
"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
"linux-kselftest@vger.kernel.org"
<linux-kselftest@vger.kernel.org>,
"linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
"oliver.upton@linux.dev" <oliver.upton@linux.dev>,
"linux-riscv@lists.infradead.org"
<linux-riscv@lists.infradead.org>
Subject: Re: [PATCH 22/35] arm64/mm: Implement map_shadow_stack()
Date: Tue, 18 Jul 2023 15:49:28 +0000 [thread overview]
Message-ID: <7a4c97f68347d4188286c543cdccaa12577cdb9e.camel@intel.com> (raw)
In-Reply-To: <8ea03eda-e630-40c5-acc1-a63f5c5b3102@sirena.org.uk>
On Tue, 2023-07-18 at 14:55 +0100, Mark Brown wrote:
> On Tue, Jul 18, 2023 at 10:10:04AM +0100, Szabolcs Nagy wrote:
>
> > uint64_t *p = map_shadow_stack(0, N*8, 0);
>
> > i'd expect p[N-1] to be the end token and p[N-2] to be the cap
> > token,
> > not p[PAGE_ALIGN(N*8)/8-2].
>
> Yes, that probably would be more helpful.
HJ made a similar request on the x86 side. He wanted an unaligned size
passed in to result in unaligned token placement.
>
> > if we allow misalligned size here (and in munmap) then i think it's
> > better to not page align. size%8!=0 || size<16 can be an error.
>
> Honestly I'd be a lot happier to just not allow misalignment but that
> raises the issue with binaries randomly not working when moved to a
> kernel with a different page size. I'll have a think but possibly
> the
> safest thing would be requiring a multiple of 4K then rounding up to
> our
> actual page size.
Someday when the x86 side is finally upstream I have a manpage for
map_shadow_stack. Any differences on the arm side would need to be
documented, but I'm not sure why there should be any differences. Like,
why not use the same flags? Or have a new flag for token+end marker
that x86 can use as well?
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2023-07-18 15:49 UTC|newest]
Thread overview: 153+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-16 21:50 [PATCH 00/35] arm64/gcs: Provide support for GCS at EL0 Mark Brown
2023-07-16 21:50 ` Mark Brown
2023-07-16 21:50 ` Mark Brown
2023-07-16 21:50 ` [PATCH 01/35] prctl: arch-agnostic prctl for shadow stack Mark Brown
2023-07-16 21:50 ` Mark Brown
2023-07-16 21:50 ` Mark Brown
2023-07-18 17:45 ` Edgecombe, Rick P
2023-07-18 17:45 ` Edgecombe, Rick P
2023-07-18 17:45 ` Edgecombe, Rick P
2023-07-18 18:54 ` Mark Brown
2023-07-18 18:54 ` Mark Brown
2023-07-18 18:54 ` Mark Brown
2023-07-16 21:50 ` [PATCH 02/35] prctl: Add flag for shadow stack writeability and push/pop Mark Brown
2023-07-16 21:50 ` Mark Brown
2023-07-16 21:50 ` Mark Brown
2023-07-18 17:47 ` Edgecombe, Rick P
2023-07-18 17:47 ` Edgecombe, Rick P
2023-07-18 17:47 ` Edgecombe, Rick P
2023-07-18 19:10 ` Mark Brown
2023-07-18 19:10 ` Mark Brown
2023-07-18 19:10 ` Mark Brown
2023-07-16 21:50 ` [PATCH 03/35] arm64: Document boot requirements for Guarded Control Stacks Mark Brown
2023-07-16 21:50 ` Mark Brown
2023-07-16 21:50 ` Mark Brown
2023-07-16 21:51 ` [PATCH 04/35] arm64/gcs: Document the ABI " Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-17 11:42 ` Jonathan Cameron
2023-07-17 11:42 ` Jonathan Cameron
2023-07-17 11:42 ` Jonathan Cameron
2023-07-19 11:44 ` Mike Rapoport
2023-07-19 11:44 ` Mike Rapoport
2023-07-19 11:44 ` Mike Rapoport
2023-07-19 13:25 ` Mark Brown
2023-07-19 13:25 ` Mark Brown
2023-07-19 13:25 ` Mark Brown
2023-07-19 14:04 ` Mike Rapoport
2023-07-19 14:04 ` Mike Rapoport
2023-07-19 14:04 ` Mike Rapoport
2023-07-16 21:51 ` [PATCH 05/35] arm64/sysreg: Add new system registers for GCS Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 06/35] arm64/sysreg: Add definitions for architected GCS caps Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 07/35] arm64/gcs: Add manual encodings of GCS instructions Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 08/35] arm64/gcs: Provide copy_to_user_gcs() Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 09/35] arm64/cpufeature: Runtime detection of Guarded Control Stack (GCS) Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 10/35] arm64/mm: Allocate PIE slots for EL0 guarded control stack Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 11/35] mm: Define VM_SHADOW_STACK for arm64 when we support GCS Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 12/35] arm64/mm: Map pages for guarded control stack Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 13/35] KVM: arm64: Manage GCS registers for guests Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 14/35] arm64: Disable traps for GCS usage at EL0 and EL1 Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 15/35] arm64/idreg: Add overrride for GCS Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 16/35] arm64/hwcap: Add hwcap " Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 17/35] arm64/traps: Handle GCS exceptions Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-17 12:12 ` Jonathan Cameron
2023-07-17 12:12 ` Jonathan Cameron
2023-07-17 12:12 ` Jonathan Cameron
2023-07-16 21:51 ` [PATCH 18/35] arm64/mm: Handle GCS data aborts Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 19/35] arm64/gcs: Context switch GCS registers for EL0 Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 20/35] arm64/gcs: Allocate a new GCS for threads with GCS enabled Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 21/35] arm64/gcs: Implement shadow stack prctl() interface Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-18 17:51 ` Edgecombe, Rick P
2023-07-18 17:51 ` Edgecombe, Rick P
2023-07-18 17:51 ` Edgecombe, Rick P
2023-07-18 19:37 ` Mark Brown
2023-07-18 19:37 ` Mark Brown
2023-07-18 19:37 ` Mark Brown
2023-07-16 21:51 ` [PATCH 22/35] arm64/mm: Implement map_shadow_stack() Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-18 9:10 ` Szabolcs Nagy
2023-07-18 9:10 ` Szabolcs Nagy
2023-07-18 9:10 ` Szabolcs Nagy
2023-07-18 13:55 ` Mark Brown
2023-07-18 13:55 ` Mark Brown
2023-07-18 13:55 ` Mark Brown
2023-07-18 15:49 ` Edgecombe, Rick P [this message]
2023-07-18 15:49 ` Edgecombe, Rick P
2023-07-18 15:49 ` Edgecombe, Rick P
2023-07-16 21:51 ` [PATCH 23/35] arm64/signal: Set up and restore the GCS context for signal handlers Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 24/35] arm64/signal: Expose GCS state in signal frames Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 25/35] arm64/ptrace: Expose GCS via ptrace and core files Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 26/35] arm64: Add Kconfig for Guarded Control Stack (GCS) Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-17 12:32 ` Jonathan Cameron
2023-07-17 12:32 ` Jonathan Cameron
2023-07-17 12:32 ` Jonathan Cameron
2023-07-16 21:51 ` [PATCH 27/35] kselftest/arm64: Verify the GCS hwcap Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 28/35] kselftest/arm64: Add GCS as a detected feature in the signal tests Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 29/35] kselftest/arm64: Add framework support for GCS to signal handling tests Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 30/35] kselftest/arm64: Allow signals tests to specify an expected si_code Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 31/35] kselftest/arm64: Always run signals tests with GCS enabled Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 32/35] kselftest/arm64: Add very basic GCS test program Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 33/35] kselftest/arm64: Add a GCS test program built with the system libc Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 34/35] selftests/arm64: Add GCS signal tests Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` [PATCH 35/35] kselftest/arm64: Enable GCS for the FP stress tests Mark Brown
2023-07-16 21:51 ` Mark Brown
2023-07-16 21:51 ` Mark Brown
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