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| author | Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> | 2020-11-27 07:44:14 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-12-03 17:01:26 +0300 |
| commit | d5fa30e6993ffcdd1859d8dab1a07a6f6c6e7c3f (patch) | |
| tree | 69bb6b2eb8e0488a5228288cc2073d47ac706191 /arch/powerpc/mm/book3s64 | |
| parent | f643fcab74c005ddfdda68c69909f03bde766ff1 (diff) | |
| download | linux-d5fa30e6993ffcdd1859d8dab1a07a6f6c6e7c3f.tar.xz | |
powerpc/book3s64/pkeys: Reset userspace AMR correctly on exec
On fork, we inherit from the parent and on exec, we should switch to default_amr values.
Also, avoid changing the AMR register value within the kernel. The kernel now runs with
different AMR values.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201127044424.40686-13-aneesh.kumar@linux.ibm.com
Diffstat (limited to 'arch/powerpc/mm/book3s64')
| -rw-r--r-- | arch/powerpc/mm/book3s64/pkeys.c | 16 |
1 files changed, 2 insertions, 14 deletions
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c index e434c0a2ee5d..355d001fa155 100644 --- a/arch/powerpc/mm/book3s64/pkeys.c +++ b/arch/powerpc/mm/book3s64/pkeys.c @@ -28,8 +28,8 @@ static u32 initial_allocation_mask __ro_after_init; * Even if we allocate keys with sys_pkey_alloc(), we need to make sure * other thread still find the access denied using the same keys. */ -static u64 default_amr = ~0x0UL; -static u64 default_iamr = 0x5555555555555555UL; +u64 default_amr __ro_after_init = ~0x0UL; +u64 default_iamr __ro_after_init = 0x5555555555555555UL; u64 default_uamor __ro_after_init; /* * Key used to implement PROT_EXEC mmap. Denies READ/WRITE @@ -396,18 +396,6 @@ void thread_pkey_regs_restore(struct thread_struct *new_thread, write_iamr(new_thread->iamr); } -void thread_pkey_regs_init(struct thread_struct *thread) -{ - if (!mmu_has_feature(MMU_FTR_PKEY)) - return; - - thread->amr = default_amr; - thread->iamr = default_iamr; - - write_amr(default_amr); - write_iamr(default_iamr); -} - int execute_only_pkey(struct mm_struct *mm) { return mm->context.execute_only_pkey; |