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| author |   Christophe Leroy <christophe.leroy@c-s.fr> | 2020-01-24 11:54:45 +0000 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2020-01-28 23:14:44 +1100 |
| commit | 3d7dfd632f9b60cfce069b4da517e6b1a1c3f613 (patch) | |
| tree | 02ec1e93d286d7c49dce90a4294f8ddc1edb3af4 /arch/powerpc/include/asm/uaccess.h | |
| parent | powerpc: Implement user_access_begin and friends (diff) | |
| download | linux-dev-3d7dfd632f9b60cfce069b4da517e6b1a1c3f613.tar.xz linux-dev-3d7dfd632f9b60cfce069b4da517e6b1a1c3f613.zip | |
powerpc: Implement user_access_save() and user_access_restore()
Implement user_access_save() and user_access_restore()
On 8xx and radix:
- On save, get the value of the associated special register then
prevent user access.
- On restore, set back the saved value to the associated special
register.
On book3s/32:
- On save, get the value stored in current->thread.kuap and prevent
user access.
- On restore, regenerate address range from the stored value and
reopen read/write access for that range.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/54f2f74938006b33c55a416674807b42ef222068.1579866752.git.christophe.leroy@c-s.fr
Diffstat (limited to '')
| -rw-r--r-- | arch/powerpc/include/asm/uaccess.h | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h index af905d7fc1df..2f500debae21 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -465,9 +465,8 @@ static __must_check inline bool user_access_begin(const void __user *ptr, size_t } #define user_access_begin user_access_begin #define user_access_end prevent_current_access_user - -static inline unsigned long user_access_save(void) { return 0UL; } -static inline void user_access_restore(unsigned long flags) { } +#define user_access_save prevent_user_access_return +#define user_access_restore restore_user_access #define unsafe_op_wrap(op, err) do { if (unlikely(op)) goto err; } while (0) #define unsafe_get_user(x, p, e) unsafe_op_wrap(__get_user_allowed(x, p), e) |