From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
To: linuxppc-dev@lists.ozlabs.org, mpe@ellerman.id.au
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>,
linuxram@us.ibm.com, bauerman@linux.ibm.com, npiggin@gmail.com
Subject: [PATCH v2 18/28] powerpc/book3s64/kuap: Restrict access to userspace based on userspace AMR
Date: Sat, 2 May 2020 16:52:19 +0530 [thread overview]
Message-ID: <20200502112229.545331-19-aneesh.kumar@linux.ibm.com> (raw)
In-Reply-To: <20200502112229.545331-1-aneesh.kumar@linux.ibm.com>
If an application has configured address protection such that read/write is
denied using pkey even the kernel should receive a FAULT on accessing the same.
This patch use user AMR value stored in pt_regs.kuap to achieve the same.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/kup.h | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/kup.h b/arch/powerpc/include/asm/book3s/64/kup.h
index 31eb0acddea9..f097d69ec2c8 100644
--- a/arch/powerpc/include/asm/book3s/64/kup.h
+++ b/arch/powerpc/include/asm/book3s/64/kup.h
@@ -279,14 +279,20 @@ static inline void set_kuap(unsigned long value)
static __always_inline void allow_user_access(void __user *to, const void __user *from,
unsigned long size, unsigned long dir)
{
+ unsigned long thread_amr = 0;
+
// 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))
+ thread_amr = current_thread_amr();
+
if (dir == KUAP_READ)
- set_kuap(AMR_KUAP_BLOCK_WRITE);
+ set_kuap(thread_amr | AMR_KUAP_BLOCK_WRITE);
else if (dir == KUAP_WRITE)
- set_kuap(AMR_KUAP_BLOCK_READ);
+ set_kuap(thread_amr | AMR_KUAP_BLOCK_READ);
else if (dir == KUAP_READ_WRITE)
- set_kuap(0);
+ set_kuap(thread_amr);
else
BUILD_BUG();
}
--
2.26.2
next prev parent reply other threads:[~2020-05-02 12:37 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-02 11:22 [PATCH v2 00/28] Kernel userspace access/execution prevention with hash translation Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 01/28] powerpc/book3s64/pkeys: Enable MMU_FTR_PKEY Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 02/28] powerpc/book3s64/kuep: Add MMU_FTR_KUEP Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 03/28] powerpc/book3s64/pkeys: Use execute_pkey_disable static key Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 04/28] powerpc/book3s64/pkeys: Use MMU_FTR_PKEY instead of pkey_disabled " Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 05/28] powerpc/book3s64/kuap: Move KUAP related function outside radix Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 06/28] powerpc/book3s64/kuep: Move KUEP " Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 07/28] powerpc/book3s64/kuap: Rename MMU_FTR_RADIX_KUAP to MMU_FTR_KUAP Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 08/28] powerpc/book3s64/kuap/kuep: Make KUAP and KUEP a subfeature of PPC_MEM_KEYS Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 09/28] powerpc/book3s64/kuap: Move UAMOR setup to key init function Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 10/28] powerpc/book3s64/kuap: Use Key 3 for kernel mapping with hash translation Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 11/28] powerpc/exec: Set thread.regs early during exec Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 12/28] powerpc/book3s64/pkeys: Store/restore userspace AMR correctly on entry and exit from kernel Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 13/28] powerpc/book3s64/kuep: Store/restore userspace IAMR " Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 14/28] powerpc/book3s64/pkeys: Inherit correctly on fork Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 15/28] powerpc/book3s64/pkeys: Reset userspace AMR correctly on exec Aneesh Kumar K.V
2020-05-07 14:25 ` Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 16/28] powerpc/ptrace-view: Use pt_regs values instead of thread_struct based one Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 17/28] powerpc/book3s64/pkeys: Don't update SPRN_AMR when in kernel mode Aneesh Kumar K.V
2020-05-02 11:22 ` Aneesh Kumar K.V [this message]
2020-05-02 11:22 ` [PATCH v2 19/28] powerpc/book3s64/kuap: Improve error reporting with KUAP Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 20/28] powerpc/book3s64/kuap: Use Key 3 to implement KUAP with hash translation Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 21/28] powerpc/book3s64/kuep: Use Key 3 to implement KUEP " Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 22/28] powerpc/book3s64/hash/kuap: Enable kuap on hash Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 23/28] powerpc/book3s64/hash/kuep: Enable KUEP " Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 24/28] powerpc/book3s64/keys: Print information during boot Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 25/28] powerpc/selftest/ptrave-pkey: Rename variables to make it easier to follow code Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 26/28] powerpc/selftest/ptrace-pkey: Update the test to mark an invalid pkey correctly Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 27/28] powerpc/selftest/ptrace-pkey: IAMR and uamor cannot be updated by ptrace Aneesh Kumar K.V
2020-05-02 11:22 ` [PATCH v2 28/28] powerpc/book3s64/keys/kuap: Reset AMR/IAMR values on kexec Aneesh Kumar K.V
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