Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752195AbcD1IIc (ORCPT ); Thu, 28 Apr 2016 04:08:32 -0400 Received: from e06smtp10.uk.ibm.com ([195.75.94.106]:45859 "EHLO e06smtp10.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751514AbcD1II0 (ORCPT ); Thu, 28 Apr 2016 04:08:26 -0400 X-IBM-Helo: d06dlp02.portsmouth.uk.ibm.com X-IBM-MailFrom: schwidefsky@de.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org;linux-s390@vger.kernel.org Date: Thu, 28 Apr 2016 10:08:19 +0200 From: Martin Schwidefsky To: Linus Torvalds Cc: linux-kernel , linux-s390 , Heiko Carstens Subject: [GIT PULL] s390 patches for 4.6-rc6 Message-ID: <20160428100819.39b39b7a@mschwide> X-Mailer: Claws Mail 3.9.3 (GTK+ 2.24.23; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16042808-0041-0000-0000-00001B770BF7 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 13468 Lines: 399 Hi Linus, please pull from the 'for-linus' branch of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git for-linus to receive the following updates: Three more bug fixes for 4.6 * Due to a race in the dynamic page table code a multi-threaded program can cause a translation specification exception. With panic_on_oops a user space program can crash the system. * An information leak with the /dev/sclp device. * A use after free in the s390 PCI code. Gerald Schaefer (1): s390/mm: fix asce_bits handling with dynamic pagetable levels Martin Schwidefsky (1): s390/sclp_ctl: fix potential information leak with /dev/sclp Sebastian Ott (1): s390/pci: fix use after free in dma_init arch/s390/include/asm/mmu.h | 2 +- arch/s390/include/asm/mmu_context.h | 28 +++++++++--- arch/s390/include/asm/pgalloc.h | 4 +- arch/s390/include/asm/processor.h | 2 +- arch/s390/include/asm/tlbflush.h | 9 ++-- arch/s390/mm/init.c | 3 +- arch/s390/mm/mmap.c | 6 +-- arch/s390/mm/pgalloc.c | 85 ++++++++++++------------------------- arch/s390/pci/pci_dma.c | 16 ++++--- drivers/s390/char/sclp_ctl.c | 12 +++--- 10 files changed, 79 insertions(+), 88 deletions(-) diff --git a/arch/s390/include/asm/mmu.h b/arch/s390/include/asm/mmu.h index d29ad95..081b2ad 100644 --- a/arch/s390/include/asm/mmu.h +++ b/arch/s390/include/asm/mmu.h @@ -11,7 +11,7 @@ typedef struct { spinlock_t list_lock; struct list_head pgtable_list; struct list_head gmap_list; - unsigned long asce_bits; + unsigned long asce; unsigned long asce_limit; unsigned long vdso_base; /* The mmu context allocates 4K page tables. */ diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h index d321469..c837b79 100644 --- a/arch/s390/include/asm/mmu_context.h +++ b/arch/s390/include/asm/mmu_context.h @@ -26,12 +26,28 @@ static inline int init_new_context(struct task_struct *tsk, mm->context.has_pgste = 0; mm->context.use_skey = 0; #endif - if (mm->context.asce_limit == 0) { + switch (mm->context.asce_limit) { + case 1UL << 42: + /* + * forked 3-level task, fall through to set new asce with new + * mm->pgd + */ + case 0: /* context created by exec, set asce limit to 4TB */ - mm->context.asce_bits = _ASCE_TABLE_LENGTH | - _ASCE_USER_BITS | _ASCE_TYPE_REGION3; mm->context.asce_limit = STACK_TOP_MAX; - } else if (mm->context.asce_limit == (1UL << 31)) { + mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH | + _ASCE_USER_BITS | _ASCE_TYPE_REGION3; + break; + case 1UL << 53: + /* forked 4-level task, set new asce with new mm->pgd */ + mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH | + _ASCE_USER_BITS | _ASCE_TYPE_REGION2; + break; + case 1UL << 31: + /* forked 2-level compat task, set new asce with new mm->pgd */ + mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH | + _ASCE_USER_BITS | _ASCE_TYPE_SEGMENT; + /* pgd_alloc() did not increase mm->nr_pmds */ mm_inc_nr_pmds(mm); } crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm)); @@ -42,7 +58,7 @@ static inline int init_new_context(struct task_struct *tsk, static inline void set_user_asce(struct mm_struct *mm) { - S390_lowcore.user_asce = mm->context.asce_bits | __pa(mm->pgd); + S390_lowcore.user_asce = mm->context.asce; if (current->thread.mm_segment.ar4) __ctl_load(S390_lowcore.user_asce, 7, 7); set_cpu_flag(CIF_ASCE); @@ -71,7 +87,7 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, { int cpu = smp_processor_id(); - S390_lowcore.user_asce = next->context.asce_bits | __pa(next->pgd); + S390_lowcore.user_asce = next->context.asce; if (prev == next) return; if (MACHINE_HAS_TLB_LC) diff --git a/arch/s390/include/asm/pgalloc.h b/arch/s390/include/asm/pgalloc.h index 9b3d9b6..da34cb6 100644 --- a/arch/s390/include/asm/pgalloc.h +++ b/arch/s390/include/asm/pgalloc.h @@ -52,8 +52,8 @@ static inline unsigned long pgd_entry_type(struct mm_struct *mm) return _REGION2_ENTRY_EMPTY; } -int crst_table_upgrade(struct mm_struct *, unsigned long limit); -void crst_table_downgrade(struct mm_struct *, unsigned long limit); +int crst_table_upgrade(struct mm_struct *); +void crst_table_downgrade(struct mm_struct *); static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address) { diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h index d6fd22e..18cdede 100644 --- a/arch/s390/include/asm/processor.h +++ b/arch/s390/include/asm/processor.h @@ -175,7 +175,7 @@ extern __vector128 init_task_fpu_regs[__NUM_VXRS]; regs->psw.mask = PSW_USER_BITS | PSW_MASK_BA; \ regs->psw.addr = new_psw; \ regs->gprs[15] = new_stackp; \ - crst_table_downgrade(current->mm, 1UL << 31); \ + crst_table_downgrade(current->mm); \ execve_tail(); \ } while (0) diff --git a/arch/s390/include/asm/tlbflush.h b/arch/s390/include/asm/tlbflush.h index ca148f7..a2e6ef3 100644 --- a/arch/s390/include/asm/tlbflush.h +++ b/arch/s390/include/asm/tlbflush.h @@ -110,8 +110,7 @@ static inline void __tlb_flush_asce(struct mm_struct *mm, unsigned long asce) static inline void __tlb_flush_kernel(void) { if (MACHINE_HAS_IDTE) - __tlb_flush_idte((unsigned long) init_mm.pgd | - init_mm.context.asce_bits); + __tlb_flush_idte(init_mm.context.asce); else __tlb_flush_global(); } @@ -133,8 +132,7 @@ static inline void __tlb_flush_asce(struct mm_struct *mm, unsigned long asce) static inline void __tlb_flush_kernel(void) { if (MACHINE_HAS_TLB_LC) - __tlb_flush_idte_local((unsigned long) init_mm.pgd | - init_mm.context.asce_bits); + __tlb_flush_idte_local(init_mm.context.asce); else __tlb_flush_local(); } @@ -148,8 +146,7 @@ static inline void __tlb_flush_mm(struct mm_struct * mm) * only ran on the local cpu. */ if (MACHINE_HAS_IDTE && list_empty(&mm->context.gmap_list)) - __tlb_flush_asce(mm, (unsigned long) mm->pgd | - mm->context.asce_bits); + __tlb_flush_asce(mm, mm->context.asce); else __tlb_flush_full(mm); } diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index c7b0451..2489b2e 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -89,7 +89,8 @@ void __init paging_init(void) asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; pgd_type = _REGION3_ENTRY_EMPTY; } - S390_lowcore.kernel_asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; + init_mm.context.asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; + S390_lowcore.kernel_asce = init_mm.context.asce; clear_table((unsigned long *) init_mm.pgd, pgd_type, sizeof(unsigned long)*2048); vmem_map_init(); diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c index 45c4daa..89cf09e 100644 --- a/arch/s390/mm/mmap.c +++ b/arch/s390/mm/mmap.c @@ -174,7 +174,7 @@ int s390_mmap_check(unsigned long addr, unsigned long len, unsigned long flags) if (!(flags & MAP_FIXED)) addr = 0; if ((addr + len) >= TASK_SIZE) - return crst_table_upgrade(current->mm, TASK_MAX_SIZE); + return crst_table_upgrade(current->mm); return 0; } @@ -191,7 +191,7 @@ s390_get_unmapped_area(struct file *filp, unsigned long addr, return area; if (area == -ENOMEM && !is_compat_task() && TASK_SIZE < TASK_MAX_SIZE) { /* Upgrade the page table to 4 levels and retry. */ - rc = crst_table_upgrade(mm, TASK_MAX_SIZE); + rc = crst_table_upgrade(mm); if (rc) return (unsigned long) rc; area = arch_get_unmapped_area(filp, addr, len, pgoff, flags); @@ -213,7 +213,7 @@ s390_get_unmapped_area_topdown(struct file *filp, const unsigned long addr, return area; if (area == -ENOMEM && !is_compat_task() && TASK_SIZE < TASK_MAX_SIZE) { /* Upgrade the page table to 4 levels and retry. */ - rc = crst_table_upgrade(mm, TASK_MAX_SIZE); + rc = crst_table_upgrade(mm); if (rc) return (unsigned long) rc; area = arch_get_unmapped_area_topdown(filp, addr, len, diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c index f6c3de2..e8b5962 100644 --- a/arch/s390/mm/pgalloc.c +++ b/arch/s390/mm/pgalloc.c @@ -76,81 +76,52 @@ static void __crst_table_upgrade(void *arg) __tlb_flush_local(); } -int crst_table_upgrade(struct mm_struct *mm, unsigned long limit) +int crst_table_upgrade(struct mm_struct *mm) { unsigned long *table, *pgd; - unsigned long entry; - int flush; - BUG_ON(limit > TASK_MAX_SIZE); - flush = 0; -repeat: + /* upgrade should only happen from 3 to 4 levels */ + BUG_ON(mm->context.asce_limit != (1UL << 42)); + table = crst_table_alloc(mm); if (!table) return -ENOMEM; + spin_lock_bh(&mm->page_table_lock); - if (mm->context.asce_limit < limit) { - pgd = (unsigned long *) mm->pgd; - if (mm->context.asce_limit <= (1UL << 31)) { - entry = _REGION3_ENTRY_EMPTY; - mm->context.asce_limit = 1UL << 42; - mm->context.asce_bits = _ASCE_TABLE_LENGTH | - _ASCE_USER_BITS | - _ASCE_TYPE_REGION3; - } else { - entry = _REGION2_ENTRY_EMPTY; - mm->context.asce_limit = 1UL << 53; - mm->context.asce_bits = _ASCE_TABLE_LENGTH | - _ASCE_USER_BITS | - _ASCE_TYPE_REGION2; - } - crst_table_init(table, entry); - pgd_populate(mm, (pgd_t *) table, (pud_t *) pgd); - mm->pgd = (pgd_t *) table; - mm->task_size = mm->context.asce_limit; - table = NULL; - flush = 1; - } + pgd = (unsigned long *) mm->pgd; + crst_table_init(table, _REGION2_ENTRY_EMPTY); + pgd_populate(mm, (pgd_t *) table, (pud_t *) pgd); + mm->pgd = (pgd_t *) table; + mm->context.asce_limit = 1UL << 53; + mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH | + _ASCE_USER_BITS | _ASCE_TYPE_REGION2; + mm->task_size = mm->context.asce_limit; spin_unlock_bh(&mm->page_table_lock); - if (table) - crst_table_free(mm, table); - if (mm->context.asce_limit < limit) - goto repeat; - if (flush) - on_each_cpu(__crst_table_upgrade, mm, 0); + + on_each_cpu(__crst_table_upgrade, mm, 0); return 0; } -void crst_table_downgrade(struct mm_struct *mm, unsigned long limit) +void crst_table_downgrade(struct mm_struct *mm) { pgd_t *pgd; + /* downgrade should only happen from 3 to 2 levels (compat only) */ + BUG_ON(mm->context.asce_limit != (1UL << 42)); + if (current->active_mm == mm) { clear_user_asce(); __tlb_flush_mm(mm); } - while (mm->context.asce_limit > limit) { - pgd = mm->pgd; - switch (pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) { - case _REGION_ENTRY_TYPE_R2: - mm->context.asce_limit = 1UL << 42; - mm->context.asce_bits = _ASCE_TABLE_LENGTH | - _ASCE_USER_BITS | - _ASCE_TYPE_REGION3; - break; - case _REGION_ENTRY_TYPE_R3: - mm->context.asce_limit = 1UL << 31; - mm->context.asce_bits = _ASCE_TABLE_LENGTH | - _ASCE_USER_BITS | - _ASCE_TYPE_SEGMENT; - break; - default: - BUG(); - } - mm->pgd = (pgd_t *) (pgd_val(*pgd) & _REGION_ENTRY_ORIGIN); - mm->task_size = mm->context.asce_limit; - crst_table_free(mm, (unsigned long *) pgd); - } + + pgd = mm->pgd; + mm->pgd = (pgd_t *) (pgd_val(*pgd) & _REGION_ENTRY_ORIGIN); + mm->context.asce_limit = 1UL << 31; + mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH | + _ASCE_USER_BITS | _ASCE_TYPE_SEGMENT; + mm->task_size = mm->context.asce_limit; + crst_table_free(mm, (unsigned long *) pgd); + if (current->active_mm == mm) set_user_asce(mm); } diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c index e595e89..1ea8c07 100644 --- a/arch/s390/pci/pci_dma.c +++ b/arch/s390/pci/pci_dma.c @@ -457,7 +457,7 @@ int zpci_dma_init_device(struct zpci_dev *zdev) zdev->dma_table = dma_alloc_cpu_table(); if (!zdev->dma_table) { rc = -ENOMEM; - goto out_clean; + goto out; } /* @@ -477,18 +477,22 @@ int zpci_dma_init_device(struct zpci_dev *zdev) zdev->iommu_bitmap = vzalloc(zdev->iommu_pages / 8); if (!zdev->iommu_bitmap) { rc = -ENOMEM; - goto out_reg; + goto free_dma_table; } rc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma, (u64) zdev->dma_table); if (rc) - goto out_reg; - return 0; + goto free_bitmap; -out_reg: + return 0; +free_bitmap: + vfree(zdev->iommu_bitmap); + zdev->iommu_bitmap = NULL; +free_dma_table: dma_free_cpu_table(zdev->dma_table); -out_clean: + zdev->dma_table = NULL; +out: return rc; } diff --git a/drivers/s390/char/sclp_ctl.c b/drivers/s390/char/sclp_ctl.c index 648cb86..ea607a4 100644 --- a/drivers/s390/char/sclp_ctl.c +++ b/drivers/s390/char/sclp_ctl.c @@ -56,6 +56,7 @@ static int sclp_ctl_ioctl_sccb(void __user *user_area) { struct sclp_ctl_sccb ctl_sccb; struct sccb_header *sccb; + unsigned long copied; int rc; if (copy_from_user(&ctl_sccb, user_area, sizeof(ctl_sccb))) @@ -65,14 +66,15 @@ static int sclp_ctl_ioctl_sccb(void __user *user_area) sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); if (!sccb) return -ENOMEM; - if (copy_from_user(sccb, u64_to_uptr(ctl_sccb.sccb), sizeof(*sccb))) { + copied = PAGE_SIZE - + copy_from_user(sccb, u64_to_uptr(ctl_sccb.sccb), PAGE_SIZE); + if (offsetof(struct sccb_header, length) + + sizeof(sccb->length) > copied || sccb->length > copied) { rc = -EFAULT; goto out_free; } - if (sccb->length > PAGE_SIZE || sccb->length < 8) - return -EINVAL; - if (copy_from_user(sccb, u64_to_uptr(ctl_sccb.sccb), sccb->length)) { - rc = -EFAULT; + if (sccb->length < 8) { + rc = -EINVAL; goto out_free; } rc = sclp_sync_request(ctl_sccb.cmdw, sccb);