lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20220121163618.351934-10-heiko@sntech.de>
Date:   Fri, 21 Jan 2022 17:36:13 +0100
From:   Heiko Stuebner <heiko@...ech.de>
To:     palmer@...belt.com, paul.walmsley@...ive.com, aou@...s.berkeley.edu
Cc:     linux-riscv@...ts.infradead.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, robh+dt@...nel.org, wefu@...hat.com,
        liush@...winnertech.com, guoren@...nel.org, atishp@...shpatra.org,
        anup@...infault.org, drew@...gleboard.org, hch@....de,
        arnd@...db.de, wens@...e.org, maxime@...no.tech,
        dlustig@...dia.com, gfavor@...tanamicro.com,
        andrea.mondelli@...wei.com, behrensj@....edu, xinhaoqu@...wei.com,
        huffman@...ence.com, mick@....forth.gr,
        allen.baum@...erantotech.com, jscheid@...tanamicro.com,
        rtrauben@...il.com, samuel@...lland.org, cmuellner@...ux.com,
        philipp.tomsich@...ll.eu, Heiko Stuebner <heiko@...ech.de>
Subject: [PATCH v5 09/14] riscv: Fix accessing pfn bits in PTEs for non-32bit variants

On rv32 the PFN part of PTEs is defined to use bits [xlen-1:10]
while on rv64 it is defined to use bits [53:10], leaving [63:54]
as reserved.

With upcoming optional extensions like svpbmt these previously
reserved bits will get used so simply right-shifting the PTE
to get the PFN won't be enough.

So introduce a _PAGE_PFN_MASK constant to mask the correct bits
for both rv32 and rv64 before shifting.

Signed-off-by: Heiko Stuebner <heiko@...ech.de>
---
 arch/riscv/include/asm/pgtable-32.h   |  8 ++++++++
 arch/riscv/include/asm/pgtable-64.h   | 14 +++++++++++---
 arch/riscv/include/asm/pgtable-bits.h |  6 ------
 arch/riscv/include/asm/pgtable.h      |  6 +++---
 4 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/arch/riscv/include/asm/pgtable-32.h b/arch/riscv/include/asm/pgtable-32.h
index 5b2e79e5bfa5..e266a4fe7f43 100644
--- a/arch/riscv/include/asm/pgtable-32.h
+++ b/arch/riscv/include/asm/pgtable-32.h
@@ -7,6 +7,7 @@
 #define _ASM_RISCV_PGTABLE_32_H
 
 #include <asm-generic/pgtable-nopmd.h>
+#include <linux/bits.h>
 #include <linux/const.h>
 
 /* Size of region mapped by a page global directory */
@@ -16,4 +17,11 @@
 
 #define MAX_POSSIBLE_PHYSMEM_BITS 34
 
+/*
+ * rv32 PTE format:
+ * | XLEN-1  10 | 9             8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
+ *       PFN      reserved for SW   D   A   G   U   X   W   R   V
+ */
+#define _PAGE_PFN_MASK  GENMASK(31, 10)
+
 #endif /* _ASM_RISCV_PGTABLE_32_H */
diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h
index 228261aa9628..706f0897437d 100644
--- a/arch/riscv/include/asm/pgtable-64.h
+++ b/arch/riscv/include/asm/pgtable-64.h
@@ -6,6 +6,7 @@
 #ifndef _ASM_RISCV_PGTABLE_64_H
 #define _ASM_RISCV_PGTABLE_64_H
 
+#include <linux/bits.h>
 #include <linux/const.h>
 
 #define PGDIR_SHIFT     30
@@ -28,6 +29,13 @@ typedef struct {
 
 #define PTRS_PER_PMD    (PAGE_SIZE / sizeof(pmd_t))
 
+/*
+ * rv64 PTE format:
+ * | 63 | 62 61 | 60 54 | 53  10 | 9             8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
+ *   N      MT     RSV    PFN      reserved for SW   D   A   G   U   X   W   R   V
+ */
+#define _PAGE_PFN_MASK  GENMASK(53, 10)
+
 static inline int pud_present(pud_t pud)
 {
 	return (pud_val(pud) & _PAGE_PRESENT);
@@ -61,12 +69,12 @@ static inline void pud_clear(pud_t *pudp)
 
 static inline pmd_t *pud_pgtable(pud_t pud)
 {
-	return (pmd_t *)pfn_to_virt(pud_val(pud) >> _PAGE_PFN_SHIFT);
+	return (pmd_t *)pfn_to_virt((pud_val(pud) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT);
 }
 
 static inline struct page *pud_page(pud_t pud)
 {
-	return pfn_to_page(pud_val(pud) >> _PAGE_PFN_SHIFT);
+	return pfn_to_page((pud_val(pud) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT);
 }
 
 static inline pmd_t pfn_pmd(unsigned long pfn, pgprot_t prot)
@@ -76,7 +84,7 @@ static inline pmd_t pfn_pmd(unsigned long pfn, pgprot_t prot)
 
 static inline unsigned long _pmd_pfn(pmd_t pmd)
 {
-	return pmd_val(pmd) >> _PAGE_PFN_SHIFT;
+	return (pmd_val(pmd) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT;
 }
 
 #define mk_pmd(page, prot)    pfn_pmd(page_to_pfn(page), prot)
diff --git a/arch/riscv/include/asm/pgtable-bits.h b/arch/riscv/include/asm/pgtable-bits.h
index 2ee413912926..4831122d559d 100644
--- a/arch/riscv/include/asm/pgtable-bits.h
+++ b/arch/riscv/include/asm/pgtable-bits.h
@@ -6,12 +6,6 @@
 #ifndef _ASM_RISCV_PGTABLE_BITS_H
 #define _ASM_RISCV_PGTABLE_BITS_H
 
-/*
- * PTE format:
- * | XLEN-1  10 | 9             8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
- *       PFN      reserved for SW   D   A   G   U   X   W   R   V
- */
-
 #define _PAGE_ACCESSED_OFFSET 6
 
 #define _PAGE_PRESENT   (1 << 0)
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index bf204e7c1f74..5cf7465a96c5 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -232,12 +232,12 @@ static inline unsigned long _pgd_pfn(pgd_t pgd)
 
 static inline struct page *pmd_page(pmd_t pmd)
 {
-	return pfn_to_page(pmd_val(pmd) >> _PAGE_PFN_SHIFT);
+	return pfn_to_page((pmd_val(pmd) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT);
 }
 
 static inline unsigned long pmd_page_vaddr(pmd_t pmd)
 {
-	return (unsigned long)pfn_to_virt(pmd_val(pmd) >> _PAGE_PFN_SHIFT);
+	return (unsigned long)pfn_to_virt((pmd_val(pmd) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT);
 }
 
 static inline pte_t pmd_pte(pmd_t pmd)
@@ -253,7 +253,7 @@ static inline pte_t pud_pte(pud_t pud)
 /* Yields the page frame number (PFN) of a page table entry */
 static inline unsigned long pte_pfn(pte_t pte)
 {
-	return (pte_val(pte) >> _PAGE_PFN_SHIFT);
+	return ((pte_val(pte) & _PAGE_PFN_MASK) >> _PAGE_PFN_SHIFT);
 }
 
 #define pte_page(x)     pfn_to_page(pte_pfn(x))
-- 
2.30.2

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ