diff options
Diffstat (limited to 'kernel/events')
| -rw-r--r-- | kernel/events/uprobes.c | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index c5f316e..93d939c8 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1774,6 +1774,7 @@ static void handle_trampoline(struct pt_regs *regs) { struct uprobe_task *utask; struct return_instance *ri, *next; + bool valid; utask = current->utask; if (!utask) @@ -1783,18 +1784,24 @@ static void handle_trampoline(struct pt_regs *regs) if (!ri) goto sigill; - next = find_next_ret_chain(ri); - /* - * TODO: we should throw out return_instance's invalidated by - * longjmp(), currently we assume that the probed function always - * returns. - */ - instruction_pointer_set(regs, ri->orig_ret_vaddr); do { - handle_uretprobe_chain(ri, regs); - ri = free_ret_instance(ri); - utask->depth--; - } while (ri != next); + /* + * We should throw out the frames invalidated by longjmp(). + * If this chain is valid, then the next one should be alive + * or NULL; the latter case means that nobody but ri->func + * could hit this trampoline on return. TODO: sigaltstack(). + */ + next = find_next_ret_chain(ri); + valid = !next || arch_uretprobe_is_alive(next, regs); + + instruction_pointer_set(regs, ri->orig_ret_vaddr); + do { + if (valid) + handle_uretprobe_chain(ri, regs); + ri = free_ret_instance(ri); + utask->depth--; + } while (ri != next); + } while (!valid); utask->return_instances = ri; return; |
