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().

Link: https://patchwork.kernel.org/comment/24798260/
Fixes: 8aa82df3c123 ("arm64: mm: add p?d_leaf() definitions")
Reported-by: Qian Cai <quic_qiancai@quicinc.com>
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>

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 94e147e5456ca9998ede2aa20d580c2f4431b9fa..dff2b483ea50927249b3392152c0afdf0c190f3d 100644 (file)
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -535,7 +535,7 @@ 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))
 #define pmd_bad(pmd)           (!pmd_table(pmd))
 
 #define pmd_leaf_size(pmd)     (pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE)
@@ -625,7 +625,7 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
 #define pud_none(pud)          (!pud_val(pud))
 #define pud_bad(pud)           (!pud_table(pud))
 #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)