powerpc/8xx: Fix pte_access_permitted() for PAGE_NONE

[ Upstream commit 5d9cea8a552ee122e21fbd5a3c5d4eb85f648e06 ]

On 8xx, PAGE_NONE is handled by setting _PAGE_NA instead of clearing
_PAGE_USER.

But then pte_user() returns 1 also for PAGE_NONE.

As _PAGE_NA prevent reads, add a specific version of pte_read()
that returns 0 when _PAGE_NA is set instead of always returning 1.

Fixes: 351750331f ("powerpc/mm: Introduce _PAGE_NA")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/57bcfbe578e43123f9ed73e040229b80f1ad56ec.1695659959.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Christophe Leroy 2023-09-25 20:31:15 +02:00 committed by Greg Kroah-Hartman
parent 077fdae908
commit 85ae11da85
2 changed files with 9 additions and 0 deletions

View File

@ -91,6 +91,13 @@ static inline pte_t pte_wrprotect(pte_t pte)
#define pte_wrprotect pte_wrprotect
static inline int pte_read(pte_t pte)
{
return (pte_val(pte) & _PAGE_RO) != _PAGE_NA;
}
#define pte_read pte_read
static inline int pte_write(pte_t pte)
{
return !(pte_val(pte) & _PAGE_RO);

View File

@ -45,7 +45,9 @@ static inline int pte_write(pte_t pte)
return pte_val(pte) & _PAGE_RW;
}
#endif
#ifndef pte_read
static inline int pte_read(pte_t pte) { return 1; }
#endif
static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; }
static inline int pte_special(pte_t pte) { return pte_val(pte) & _PAGE_SPECIAL; }
static inline int pte_none(pte_t pte) { return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; }