From e13b73dd9c8003993b171173ba803363faf74238 Mon Sep 17 00:00:00 2001 From: Dmitry Safonov Date: Tue, 14 Mar 2017 14:41:26 +0300 Subject: [PATCH] x86/hugetlb: Adjust to the new native/compat mmap bases Commit 1b028f784e8c introduced two mmap() bases for 32-bit syscalls and for 64-bit syscalls. The mmap() code in x86 was modified to handle the separation, but the patch series missed to update the hugetlb code. As a consequence a 32bit application mapping a file on hugetlbfs uses the 64-bit mmap base for address space allocation, which fails. Adjust the hugetlb mapping code to use the proper bases depending on the syscall invocation mode (64-bit or compat). [ tglx: Massaged changelog and switched from asm/compat.h to linux/compat.h ] Fixes: commit 1b028f784e8c ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()") Reported-by: kernel test robot Signed-off-by: Dmitry Safonov Cc: 0x7f454c46@gmail.com Cc: linux-mm@kvack.org Cc: Andy Lutomirski Cc: Cyrill Gorcunov Cc: Borislav Petkov Cc: "Kirill A. Shutemov" Link: http://lkml.kernel.org/r/20170314114126.9280-1-dsafonov@virtuozzo.com Signed-off-by: Thomas Gleixner --- arch/x86/include/asm/elf.h | 1 + arch/x86/kernel/sys_x86_64.c | 12 ------------ arch/x86/mm/hugetlbpage.c | 9 ++++++--- arch/x86/mm/mmap.c | 14 ++++++++++++++ 4 files changed, 21 insertions(+), 15 deletions(-) diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index ac5be5ba8527..d4d3ed456cb7 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -305,6 +305,7 @@ static inline int mmap_is_ia32(void) extern unsigned long tasksize_32bit(void); extern unsigned long tasksize_64bit(void); +extern unsigned long get_mmap_base(int is_legacy); #ifdef CONFIG_X86_32 diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c index 63e89dfc808a..207b8f2582c7 100644 --- a/arch/x86/kernel/sys_x86_64.c +++ b/arch/x86/kernel/sys_x86_64.c @@ -100,18 +100,6 @@ out: return error; } -static unsigned long get_mmap_base(int is_legacy) -{ - struct mm_struct *mm = current->mm; - -#ifdef CONFIG_HAVE_ARCH_COMPAT_MMAP_BASES - if (in_compat_syscall()) - return is_legacy ? mm->mmap_compat_legacy_base - : mm->mmap_compat_base; -#endif - return is_legacy ? mm->mmap_legacy_base : mm->mmap_base; -} - static void find_start_end(unsigned long flags, unsigned long *begin, unsigned long *end) { diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c index c5066a260803..302f43fd9c28 100644 --- a/arch/x86/mm/hugetlbpage.c +++ b/arch/x86/mm/hugetlbpage.c @@ -12,10 +12,12 @@ #include #include #include +#include #include #include #include #include +#include #if 0 /* This is just for testing */ struct page * @@ -82,8 +84,9 @@ static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file, info.flags = 0; info.length = len; - info.low_limit = current->mm->mmap_legacy_base; - info.high_limit = TASK_SIZE; + info.low_limit = get_mmap_base(1); + info.high_limit = in_compat_syscall() ? + tasksize_32bit() : tasksize_64bit(); info.align_mask = PAGE_MASK & ~huge_page_mask(h); info.align_offset = 0; return vm_unmapped_area(&info); @@ -100,7 +103,7 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, info.flags = VM_UNMAPPED_AREA_TOPDOWN; info.length = len; info.low_limit = PAGE_SIZE; - info.high_limit = current->mm->mmap_base; + info.high_limit = get_mmap_base(0); info.align_mask = PAGE_MASK & ~huge_page_mask(h); info.align_offset = 0; addr = vm_unmapped_area(&info); diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c index 529ab79800af..19ad095b41df 100644 --- a/arch/x86/mm/mmap.c +++ b/arch/x86/mm/mmap.c @@ -30,6 +30,7 @@ #include #include #include +#include #include struct va_alignment __read_mostly va_align = { @@ -153,6 +154,19 @@ void arch_pick_mmap_layout(struct mm_struct *mm) #endif } +unsigned long get_mmap_base(int is_legacy) +{ + struct mm_struct *mm = current->mm; + +#ifdef CONFIG_HAVE_ARCH_COMPAT_MMAP_BASES + if (in_compat_syscall()) { + return is_legacy ? mm->mmap_compat_legacy_base + : mm->mmap_compat_base; + } +#endif + return is_legacy ? mm->mmap_legacy_base : mm->mmap_base; +} + const char *arch_vma_name(struct vm_area_struct *vma) { if (vma->vm_flags & VM_MPX) -- 2.20.1