BACKPORT: arm64: mm: fix p?d_leaf()

The pmd_leaf() is used to test a leaf mapped PMD, however, it misses
the PROT_NONE mapped PMD on arm64.  Fix it.  A real world issue [1]
caused by this was reported by Qian Cai. Also fix pud_leaf().
Moto-CRs-Fixed:(CR)

Link: https://patchwork.kernel.org/comment/24798260/ [1]
Fixes: 8aa82df3c123 ("arm64: mm: add p?d_leaf() definitions")
Reported-by: Qian Cai <quic_qiancai@quicinc.com>
Change-Id: I3b632d653c4e00a8825e1cc626d935ca5cbac194
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Link: https://lore.kernel.org/r/20220422060033.48711-1-songmuchun@bytedance.com
Signed-off-by: Will Deacon <will@kernel.org>
(cherry picked from commit 23bc8f69f0eceecbb87c3801d2e48827d2dca92b)
Bug: 261052246
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-on: https://gerrit.mot.com/2491781
SME-Granted: SME Approvals Granted
SLTApproved: Slta Waiver
Tested-by: Jira Key
Reviewed-by: Xiangpo Zhao <zhaoxp3@motorola.com>
Submit-Approved: Jira Key

arch/arm64/include/asm/pgtable.h

@@ -455,7 +455,7 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 				 PMD_TYPE_TABLE)
 #define pmd_sect(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
 				 PMD_TYPE_SECT)
-#define pmd_leaf(pmd)		pmd_sect(pmd)
+#define pmd_leaf(pmd)		(pmd_present(pmd) && !pmd_table(pmd))
 
 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
 static inline bool pud_sect(pud_t pud) { return false; }
@@ -547,7 +547,7 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
 #define pud_none(pud)		(!pud_val(pud))
 #define pud_bad(pud)		(!(pud_val(pud) & PUD_TABLE_BIT))
 #define pud_present(pud)	pte_present(pud_pte(pud))
-#define pud_leaf(pud)		pud_sect(pud)
+#define pud_leaf(pud)		(pud_present(pud) && !pud_table(pud))
 #define pud_valid(pud)		pte_valid(pud_pte(pud))
 
 static inline void set_pud(pud_t *pudp, pud_t pud)