diff options
| -rw-r--r-- | include/linux/sched.h | 2 | ||||
| -rw-r--r-- | include/linux/uprobes.h | 5 | ||||
| -rw-r--r-- | kernel/events/uprobes.c | 22 | ||||
| -rw-r--r-- | kernel/fork.c | 1 |
4 files changed, 29 insertions, 1 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index b8c86648a2f9..3667c332e61d 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -446,6 +446,8 @@ extern int get_dumpable(struct mm_struct *mm); #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */ #define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */ +#define MMF_HAS_UPROBES 19 /* might have uprobes */ + #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK) struct sighand_struct { diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index 03ae547c1c31..4a37ab153247 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -108,6 +108,7 @@ extern int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_con extern void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc); extern int uprobe_mmap(struct vm_area_struct *vma); extern void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end); +extern void uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm); extern void uprobe_free_utask(struct task_struct *t); extern void uprobe_copy_process(struct task_struct *t); extern unsigned long __weak uprobe_get_swbp_addr(struct pt_regs *regs); @@ -138,6 +139,10 @@ static inline void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end) { } +static inline void +uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm) +{ +} static inline void uprobe_notify_resume(struct pt_regs *regs) { } diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 3e2996b809be..33870b17e1dd 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -647,6 +647,7 @@ static int install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, struct vm_area_struct *vma, unsigned long vaddr) { + bool first_uprobe; int ret; /* @@ -678,7 +679,17 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, uprobe->flags |= UPROBE_COPY_INSN; } + /* + * set MMF_HAS_UPROBES in advance for uprobe_pre_sstep_notifier(), + * the task can hit this breakpoint right after __replace_page(). + */ + first_uprobe = !test_bit(MMF_HAS_UPROBES, &mm->flags); + if (first_uprobe) + set_bit(MMF_HAS_UPROBES, &mm->flags); + ret = set_swbp(&uprobe->arch, mm, vaddr); + if (ret && first_uprobe) + clear_bit(MMF_HAS_UPROBES, &mm->flags); return ret; } @@ -1032,6 +1043,9 @@ void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned lon if (!atomic_read(&vma->vm_mm->mm_users)) /* called by mmput() ? */ return; + if (!test_bit(MMF_HAS_UPROBES, &vma->vm_mm->flags)) + return; + /* TODO: unmapping uprobe(s) will need more work */ } @@ -1142,6 +1156,12 @@ void uprobe_reset_state(struct mm_struct *mm) mm->uprobes_state.xol_area = NULL; } +void uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm) +{ + if (test_bit(MMF_HAS_UPROBES, &oldmm->flags)) + set_bit(MMF_HAS_UPROBES, &newmm->flags); +} + /* * - search for a free slot. */ @@ -1507,7 +1527,7 @@ int uprobe_pre_sstep_notifier(struct pt_regs *regs) { struct uprobe_task *utask; - if (!current->mm) + if (!current->mm || !test_bit(MMF_HAS_UPROBES, ¤t->mm->flags)) return 0; utask = current->utask; diff --git a/kernel/fork.c b/kernel/fork.c index 912b6f6fe5b8..cbb5f9fcd3e8 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -353,6 +353,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) down_write(&oldmm->mmap_sem); flush_cache_dup_mm(oldmm); + uprobe_dup_mmap(oldmm, mm); /* * Not linked in yet - no deadlock potential: */ |