[SPARC64]: Do not allow mapping pages within 4GB of 64-bit VA hole. (8bcd1741) · Commits · 戴 / test

arch/sparc64/kernel/sys_sparc.c

+68 −22

Original line number	Diff line number	Diff line
		@@ -33,14 +33,55 @@

		/* #define DEBUG_UNIMP_SYSCALL */

		/* XXX Make this per-binary type, this way we can detect the type of
		* XXX a binary. Every Sparc executable calls this very early on.
		*/
		asmlinkage unsigned long sys_getpagesize(void)
		{
		return PAGE_SIZE;
		}

		#define VA_EXCLUDE_START (0x0000080000000000UL - (1UL << 32UL))
		#define VA_EXCLUDE_END (0xfffff80000000000UL + (1UL << 32UL))

		/* Does addr --> addr+len fall within 4GB of the VA-space hole or
		* overflow past the end of the 64-bit address space?
		*/
		static inline int invalid_64bit_range(unsigned long addr, unsigned long len)
		{
		unsigned long va_exclude_start, va_exclude_end;

		va_exclude_start = VA_EXCLUDE_START;
		va_exclude_end = VA_EXCLUDE_END;

		if (unlikely(len >= va_exclude_start))
		return 1;

		if (unlikely((addr + len) < addr))
		return 1;

		if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) \|\|
		((addr + len) >= va_exclude_start &&
		(addr + len) < va_exclude_end)))
		return 1;

		return 0;
		}

		/* Does start,end straddle the VA-space hole? */
		static inline int straddles_64bit_va_hole(unsigned long start, unsigned long end)
		{
		unsigned long va_exclude_start, va_exclude_end;

		va_exclude_start = VA_EXCLUDE_START;
		va_exclude_end = VA_EXCLUDE_END;

		if (likely(start < va_exclude_start && end < va_exclude_start))
		return 0;

		if (likely(start >= va_exclude_end && end >= va_exclude_end))
		return 0;

		return 1;
		}

		#define COLOUR_ALIGN(addr,pgoff) \
		((((addr)+SHMLBA-1)&~(SHMLBA-1)) + \
		(((pgoff)<<PAGE_SHIFT) & (SHMLBA-1)))
		@@ -65,7 +106,7 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi

		if (test_thread_flag(TIF_32BIT))
		task_size = 0xf0000000UL;
		if (len > task_size \|\| len > -PAGE_OFFSET)
		if (len > task_size \|\| len >= VA_EXCLUDE_START)
		return -ENOMEM;

		do_color_align = 0;
		@@ -100,9 +141,10 @@ full_search:

		for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
		/* At this point: (!vma \|\| addr < vma->vm_end). */
		if (addr < PAGE_OFFSET && -PAGE_OFFSET - len < addr) {
		addr = PAGE_OFFSET;
		vma = find_vma(mm, PAGE_OFFSET);
		if (addr < VA_EXCLUDE_START &&
		(addr + len) >= VA_EXCLUDE_START) {
		addr = VA_EXCLUDE_END;
		vma = find_vma(mm, VA_EXCLUDE_END);
		}
		if (task_size < addr) {
		if (start_addr != TASK_UNMAPPED_BASE) {
		@@ -174,12 +216,12 @@ unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, u
		asmlinkage unsigned long sparc_brk(unsigned long brk)
		{
		/* People could try to be nasty and use ta 0x6d in 32bit programs */
		if (test_thread_flag(TIF_32BIT) &&
		brk >= 0xf0000000UL)
		if (test_thread_flag(TIF_32BIT) && brk >= 0xf0000000UL)
		return current->mm->brk;

		if ((current->mm->brk & PAGE_OFFSET) != (brk & PAGE_OFFSET))
		if (unlikely(straddles_64bit_va_hole(current->mm->brk, brk)))
		return current->mm->brk;

		return sys_brk(brk);
		}

		@@ -340,13 +382,16 @@ asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
		retval = -EINVAL;

		if (test_thread_flag(TIF_32BIT)) {
		if (len > 0xf0000000UL \|\|
		((flags & MAP_FIXED) && addr > 0xf0000000UL - len))
		if (len >= 0xf0000000UL)
		goto out_putf;

		if ((flags & MAP_FIXED) && addr > 0xf0000000UL - len)
		goto out_putf;
		} else {
		if (len > -PAGE_OFFSET \|\|
		((flags & MAP_FIXED) &&
		addr < PAGE_OFFSET && addr + len > -PAGE_OFFSET))
		if (len >= VA_EXCLUDE_START)
		goto out_putf;

		if ((flags & MAP_FIXED) && invalid_64bit_range(addr, len))
		goto out_putf;
		}

		@@ -365,9 +410,9 @@ asmlinkage long sys64_munmap(unsigned long addr, size_t len)
		{
		long ret;

		if (len > -PAGE_OFFSET \|\|
		(addr < PAGE_OFFSET && addr + len > -PAGE_OFFSET))
		if (invalid_64bit_range(addr, len))
		return -EINVAL;

		down_write(&current->mm->mmap_sem);
		ret = do_munmap(current->mm, addr, len);
		up_write(&current->mm->mmap_sem);
		@@ -384,18 +429,19 @@ asmlinkage unsigned long sys64_mremap(unsigned long addr,
		{
		struct vm_area_struct *vma;
		unsigned long ret = -EINVAL;

		if (test_thread_flag(TIF_32BIT))
		goto out;
		if (old_len > -PAGE_OFFSET \|\| new_len > -PAGE_OFFSET)
		if (unlikely(new_len >= VA_EXCLUDE_START))
		goto out;
		if (addr < PAGE_OFFSET && addr + old_len > -PAGE_OFFSET)
		if (unlikely(invalid_64bit_range(addr, old_len)))
		goto out;

		down_write(&current->mm->mmap_sem);
		if (flags & MREMAP_FIXED) {
		if (new_addr < PAGE_OFFSET &&
		new_addr + new_len > -PAGE_OFFSET)
		if (invalid_64bit_range(new_addr, new_len))
		goto out_sem;
		} else if (addr < PAGE_OFFSET && addr + new_len > -PAGE_OFFSET) {
		} else if (invalid_64bit_range(addr, new_len)) {
		unsigned long map_flags = 0;
		struct file *file = NULL;

include/asm-sparc64/a.out.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -95,7 +95,9 @@ struct relocation_info /* used when header.a_machtype == M_SPARC */

		#ifdef __KERNEL__

		#define STACK_TOP (test_thread_flag(TIF_32BIT) ? 0xf0000000 : 0x80000000000L)
		#define STACK_TOP (test_thread_flag(TIF_32BIT) ? \
		0xf0000000 : \
		(0x0000080000000000UL - (1UL << 32UL)))

		#endif

include/asm-sparc64/page.h

+2 −1

Original line number	Diff line number	Diff line
		@@ -107,7 +107,8 @@ typedef unsigned long pgprot_t;
		#endif

		#define TASK_UNMAPPED_BASE (test_thread_flag(TIF_32BIT) ? \
		(_AC(0x0000000070000000,UL)) : (PAGE_OFFSET))
		(_AC(0x0000000070000000,UL)) : \
		(_AC(0xfffff80000000000,UL) + (1UL << 32UL)))

		#endif /* !(__ASSEMBLY__) */

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