diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c index 69309cd56fdf3fb28c8b7732297471ba69f46686..33093fdedb02d28602f2f634338adc16dea7eee6 100644 --- a/arch/x86/mm/dump_pagetables.c +++ b/arch/x86/mm/dump_pagetables.c @@ -249,10 +249,22 @@ static void note_wx(struct pg_state *st, unsigned long addr) (void *)st->start_address); } -static inline pgprotval_t effective_prot(pgprotval_t prot1, pgprotval_t prot2) +static void effective_prot(struct ptdump_state *pt_st, int level, u64 val) { - return (prot1 & prot2 & (_PAGE_USER | _PAGE_RW)) | - ((prot1 | prot2) & _PAGE_NX); + struct pg_state *st = container_of(pt_st, struct pg_state, ptdump); + pgprotval_t prot = val & PTE_FLAGS_MASK; + pgprotval_t effective; + + if (level > 0) { + pgprotval_t higher_prot = st->prot_levels[level - 1]; + + effective = (higher_prot & prot & (_PAGE_USER | _PAGE_RW)) | + ((higher_prot | prot) & _PAGE_NX); + } else { + effective = prot; + } + + st->prot_levels[level] = effective; } /* @@ -270,16 +282,10 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level, struct seq_file *m = st->seq; new_prot = val & PTE_FLAGS_MASK; - - if (level > 0) { - new_eff = effective_prot(st->prot_levels[level - 1], - new_prot); - } else { - new_eff = new_prot; - } - - if (level >= 0) - st->prot_levels[level] = new_eff; + if (!val) + new_eff = 0; + else + new_eff = st->prot_levels[level]; /* * If we have a "break" in the series, we need to flush the state that @@ -374,6 +380,7 @@ static void ptdump_walk_pgd_level_core(struct seq_file *m, struct pg_state st = { .ptdump = { .note_page = note_page, + .effective_prot = effective_prot, .range = ptdump_ranges }, .level = -1, diff --git a/include/linux/ptdump.h b/include/linux/ptdump.h index a67065c403c38e0db30c9d929757e8349a108671..ac01502763bfe644f72aa313c022830806db5bbc 100644 --- a/include/linux/ptdump.h +++ b/include/linux/ptdump.h @@ -14,6 +14,7 @@ struct ptdump_state { /* level is 0:PGD to 4:PTE, or -1 if unknown */ void (*note_page)(struct ptdump_state *st, unsigned long addr, int level, unsigned long val); + void (*effective_prot)(struct ptdump_state *st, int level, u64 val); const struct ptdump_range *range; }; diff --git a/mm/ptdump.c b/mm/ptdump.c index 26208d0d03b7a9745981259801e445cf67bb7f1c..f4ce916f56020736b9f5804c11c28dd94aa6b7f7 100644 --- a/mm/ptdump.c +++ b/mm/ptdump.c @@ -36,6 +36,9 @@ static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr, return note_kasan_page_table(walk, addr); #endif + if (st->effective_prot) + st->effective_prot(st, 0, pgd_val(val)); + if (pgd_leaf(val)) st->note_page(st, addr, 0, pgd_val(val)); @@ -53,6 +56,9 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr, return note_kasan_page_table(walk, addr); #endif + if (st->effective_prot) + st->effective_prot(st, 1, p4d_val(val)); + if (p4d_leaf(val)) st->note_page(st, addr, 1, p4d_val(val)); @@ -70,6 +76,9 @@ static int ptdump_pud_entry(pud_t *pud, unsigned long addr, return note_kasan_page_table(walk, addr); #endif + if (st->effective_prot) + st->effective_prot(st, 2, pud_val(val)); + if (pud_leaf(val)) st->note_page(st, addr, 2, pud_val(val)); @@ -87,6 +96,8 @@ static int ptdump_pmd_entry(pmd_t *pmd, unsigned long addr, return note_kasan_page_table(walk, addr); #endif + if (st->effective_prot) + st->effective_prot(st, 3, pmd_val(val)); if (pmd_leaf(val)) st->note_page(st, addr, 3, pmd_val(val)); @@ -97,8 +108,12 @@ static int ptdump_pte_entry(pte_t *pte, unsigned long addr, unsigned long next, struct mm_walk *walk) { struct ptdump_state *st = walk->private; + pte_t val = READ_ONCE(*pte); + + if (st->effective_prot) + st->effective_prot(st, 4, pte_val(val)); - st->note_page(st, addr, 4, pte_val(READ_ONCE(*pte))); + st->note_page(st, addr, 4, pte_val(val)); return 0; }