diff options
| -rw-r--r-- | arch/m68k/kernel/sys_m68k.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/arch/m68k/kernel/sys_m68k.c b/arch/m68k/kernel/sys_m68k.c index 3a480b3df0d6..9aa01adb407f 100644 --- a/arch/m68k/kernel/sys_m68k.c +++ b/arch/m68k/kernel/sys_m68k.c @@ -376,7 +376,6 @@ cache_flush_060 (unsigned long addr, int scope, int cache, unsigned long len) asmlinkage int sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len) { - struct vm_area_struct *vma; int ret = -EINVAL; if (scope < FLUSH_SCOPE_LINE || scope > FLUSH_SCOPE_ALL || @@ -389,17 +388,21 @@ sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len) if (!capable(CAP_SYS_ADMIN)) goto out; } else { + struct vm_area_struct *vma; + + /* Check for overflow. */ + if (addr + len < addr) + goto out; + /* * Verify that the specified address region actually belongs * to this process. */ - vma = find_vma (current->mm, addr); ret = -EINVAL; - /* Check for overflow. */ - if (addr + len < addr) - goto out; - if (vma == NULL || addr < vma->vm_start || addr + len > vma->vm_end) - goto out; + down_read(¤t->mm->mmap_sem); + vma = find_vma(current->mm, addr); + if (!vma || addr < vma->vm_start || addr + len > vma->vm_end) + goto out_unlock; } if (CPU_IS_020_OR_030) { @@ -429,7 +432,7 @@ sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len) __asm__ __volatile__ ("movec %0, %%cacr" : : "r" (cacr)); } ret = 0; - goto out; + goto out_unlock; } else { /* * 040 or 060: don't blindly trust 'scope', someone could @@ -446,6 +449,8 @@ sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len) ret = cache_flush_060 (addr, scope, cache, len); } } +out_unlock: + up_read(¤t->mm->mmap_sem); out: return ret; } |