diff options
Diffstat (limited to 'arch/sparc64/kernel')
-rw-r--r-- | arch/sparc64/kernel/sys_sparc.c | 90 |
1 files changed, 68 insertions, 22 deletions
diff --git a/arch/sparc64/kernel/sys_sparc.c b/arch/sparc64/kernel/sys_sparc.c index 5f8c822a2b4..095db723bb8 100644 --- a/arch/sparc64/kernel/sys_sparc.c +++ b/arch/sparc64/kernel/sys_sparc.c @@ -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(¤t->mm->mmap_sem); ret = do_munmap(current->mm, addr, len); up_write(¤t->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(¤t->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; |