diff options
-rw-r--r-- | arch/blackfin/kernel/ptrace.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/arch/blackfin/kernel/ptrace.c b/arch/blackfin/kernel/ptrace.c index e1f88e028cfe..8b8fe671b1a6 100644 --- a/arch/blackfin/kernel/ptrace.c +++ b/arch/blackfin/kernel/ptrace.c @@ -117,6 +117,7 @@ put_reg(struct task_struct *task, unsigned long regno, unsigned long data) int is_user_addr_valid(struct task_struct *child, unsigned long start, unsigned long len) { + bool valid; struct vm_area_struct *vma; struct sram_list_struct *sraml; @@ -124,9 +125,12 @@ is_user_addr_valid(struct task_struct *child, unsigned long start, unsigned long if (start + len < start) return -EIO; + down_read(&child->mm->mmap_sem); vma = find_vma(child->mm, start); - if (vma && start >= vma->vm_start && start + len <= vma->vm_end) - return 0; + valid = vma && start >= vma->vm_start && start + len <= vma->vm_end; + up_read(&child->mm->mmap_sem); + if (valid) + return 0; for (sraml = child->mm->context.sram_list; sraml; sraml = sraml->next) if (start >= (unsigned long)sraml->addr |