On 10/16/2017 10:55 PM, Richard Weinberger wrote:
Am Montag, 16. Oktober 2017, 22:50:43 CEST schrieb Daniel Borkmann:
struct task_struct *task = current;
+ task_lock(task);
strncpy(buf, task->comm, size);
+ task_unlock(task);
Wouldn't this potentially lead to a deadlock? E.g. you attach yourself
to task_lock() / spin_lock() / etc, and then the BPF prog triggers the
bpf_get_current_comm() taking the lock again ...
Yes, but doesn't the same apply to the use case when I attach to strncpy()
and run bpf_get_current_comm()?
You mean due to recursion? In that case trace_call_bpf() would bail out
due to the bpf_prog_active counter.
